Study and Design on Ironless Permanent Magnet Motor

　　Study and Design on Ironless Permanent Magnet Motor
　　This paper studied high performance ironless permanent magnet motor. A 2.2kW prototype was turned out, and gains series of results which have certain academic level and engineering practical worth. This paper consists of several parts thereinafter:Firstly, the theory of the Halbach magnet array is analyzed, then taking a 8-pole motor as an example, the characteristic of the Halbach magnet array is analyzed either. Aiming at the multifold structure of the ironless permanent magnet motor, the flux density distribution of the gap and the yoke, which is produced by both Halbach rubber magnetic sheet magnet array and the conventional magnet array, is figured out. The merit and the flaw of the both array are revealed according to the contrasted result. Finally the gap flux density characteristic of the dual rotor is analyzed.The computer means of the key parameters including the gap flux density, the slot leak reactance, the armature reactance and the calculated length of the armature is studied and the formula is also put forward. The design method and the molding means of the slotless armature are analyzed. Explore the characteristic between power and power-angle which is different from the conventional http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php permanent magnet motor.According to the design features of ironless permanent magnet motor, computer-aided design software is developed. The software is composed of the FORTRAN language used to compile the program of motor design and the VB language used to compile the friendly interface. The two languages are linked by Dynamic-Link Libraries that the creation and usage is discussed particularly.After summarizing the experience of the design and the test of the low power ironless permanent magnet motors, a 2.2kW prototype has been designed and the tests have been finished. According to the test result, the ironless permanent magnet motor has such merits as lower voice, higher efficiency, and so on. The key parameters and the test results are written in this paper.

Micro-structure-influence Research on the Double Phase Nano-composite Permanent Magnet

　　Micro-structure-influence Research on the Double Phase Nano-composite Permanent Magnet
　　As new permanent magnets, double-phase nanocomposite permanent magnets have recently attracted considerable attention. This type of alloys integrates advantages of hard magnetic phase’s high magnetocrystalline anisotropy and soft magnetic phase’s high saturation magnetization, and obtains the excellent magnetic properties through exchange-coupled interaction on a scale of the order nm. Theoretical estimation indicates that double-phase nanocomposite permanent magnet material’s energy product may reach as high as 800kJ/m3, higher than any kind of single-phase permanent-magnet material. This kind of material also has characteristics of low rare earth content and Block Ceramic Magnets good chemical stability, Therefore, it is of great practical value and to be the new generation of low price caking permanent-magnet material, it will have promising application prospect.Firstly, this author studied the take-shape craft of double-phase nanocomposite permanent magnet material, including the performance by pressure and time’s maintenance to magnet’s density and the magnetism. The result indicates that the magnet density increases along with the pressure and time.
　　The magnet density reaches the biggest one when pressure is 600MPa and time is 150s. When the pressure or the time is continually increased, the magnet density will no longer increase, there is possibility to create break interior and reduce the production efficiency. This suppressed craft was still used in following experiments.Secondly, the author studied the agglutinate craft of double-phase nanocomposite permanent magnet material, which had two variables: high agglutinates- temperature and heat preservation time. Had determined the elevation of temperature mechanism according to the differential-thermal analysis curve, the elevation of temperature speed is 3~5℃. Three http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php specimens were selected in experiment, their serial numbers were3#、4#、5#, separately used in different high agglutinates-temperature, and simultaneously different heat preservation time , the result is that the 4# is burn to be most compact, and the compactness is the highest when the heat preservation time is the 150min. According to the micro analysis, the Crystal grain of test specimen has ruled size, and the distribution is even, and no crystalless phase exists.Finally, the author studied the influence of adding element on the double-phase nanocomposite permanent magnet material, the author choose the representative replacement element Co and doping element Mo in adding element, the recruitment control is below 1.0wt%, the experiment is divided into six groups, different group with different element addition and different recruitment. Concluded by the micro analysis, among the six groups, the foemer of group adding with Mo element is better than that adding with Co element. It has more tiny-even crystal grain, and among the group adding with Mo element, 0.5wt%Mo is the best one. The final result indicates that Co element actually has enhances the magnetism performance influence on craft of Nd-Fe-B, and the Mo element mainly played the thin crystal grain role, the magnetism performance had the enhancement.

The Study and Design of MW Permanent-magnet Synchronous Generator in the Wind Power Generation System

　　The Study and Design of MW Permanent-magnet Synchronous Generator in the Wind Power Generation System
　　With the increasing of world population and deteriorating of the energy resource problem, all countries come to realize importance and urgency of imploring new sources of energy. Wind power generating is greatly favored because of its character of no pollution and inexhaustibility. Nowadays, using variable speed constant frequency (vscf) generation technology to improve the output power of wind power generator is becoming the research hotspot of wind power system. Wind power generator is developing to the direct of having high reliability, low maintenance and cost, high efficiency.MW permanent magnet synchronous generator with simple structure, so good ventilation, large neodymium standard state moment of inertia, high reliability and high efficiency can be droved directly by wind power machine. It can be used in the direct-drive wind power generation.In this paper, the research status of the wind power generation is summarized. The study history and developing future of the wind power generator are introduced. The rotor magnetic circuit structure and work principle of the generator are studied in detail, the function capability of it is analysied mainly. According to the characteristic of the MW permanent magnet synchronous generator, the paper studies the choosing of the main dimension of the generator, electromagnetic load, rotor magnetic circuit structure, magnetic material and armature winding. Based on the common design method of the permanent magnet synchronous generator, the http://www.999magnet.com/products/112-neodymium-standard-state paper uses RMxprt software of Ansoft Company to design the MW permanent magnet wind power synchronous generator. The modle of the generator has two different loads, one is independent resistance load and the other is infinity electrical network load. The two different loads are parametric analysed. The MW permanent magnet synchronous generator’s static electromagnetic field and transient electromagnetic field have been analyzed in detail by the Maxwell 2D. The result of analysis compared with the calculative result of the RMxprt confirmed the validity of the MW permanent magnet wind power synchronous generator.

Research on the Key Technologies of Bearingless Permanent Magnet Synchronous Slice Motor

　　Research on the Key Technologies of Bearingless Permanent Magnet Synchronous Slice Motor
　　In this paper, the working principle and control strategy of bearingless permanent magnet synchronous slice motor are introduced. Control simulation upon this motor is done using Matlab/Simulink, through which control process of producing radial suspension forces are analyzed vividly. Based on the research on the key technologies of bearingless permanent magnet synchronous slice motor, the main research object—the vecotor control based on SVPWM(Space Vector Pulse neodymium standard state Width Modulate) and sensorless control based on MRAS(Model Reference Adapt System) of common PMSM(permanent magnet synchronous motor) is educed. Then the theoretical analysis and simulation study of the tow methods mentioned above are done as well.The inverter is designed with intelligent power model-PS21564, and then, the results from the tests of the inverter indicate that this inverter can satisfy the hardware requirements of the control system opon permanent magnet http://www.999magnet.com/products/112-neodymium-standard-state synchronous motor. The DSP software program of motor control was compiled. At last, the experiment of the motor control is carried out, which proved the feasibility of the tow control strategy mentioned above. Experimental results show that the research in this paper obtains the anticipated aim, and which lay a good foundation for further study as well.

Research of NdFeB Permanent Magnet Synchronous Submersible Motor for Screw Pump

　　Research of NdFeB Permanent Magnet Synchronous Submersible Motor for Screw Pump
　　The screw pump is one of the valid equipments to exploit crude oil which has high viscosity and contains a lot of sand. The screw pump can only work effectively at low speed and its best rotational speed is around 100-500r/min normally. The existing submersible motors can not be applied to screw pumps directly because of its high rotational speed. Therefore, the development of low-speed and high-torque permanent magnet synchronous submersible motor (PMSSM) for screw pump has become one of the currently significant tasks.PMSSM for screw pump is a vertical three-phase induction motor. It adopts lathy structure of subsection of stator and rotor: each neodymium prices subsection of stator combines with non-magnetic substance and each subsection of rotor combines with rotor bearing.
　　There is full of appropriative lubricating oil between stator and rotor. And there are permanent magnets in the PMSSM rotor.This paper researches on the influence of PMSSM characteristic which is subsection of stator and rotor and filled with the lubricant upon motor performances according to its special structure. The prototype has ten poles and thirty-six stator slots and adopts fractional winding slot. Stator inner diameter dimension of the motor is difficult to define because the range of slenderness ratio is very large. A new method is adopted to calculate stator inner diameter dimension in this paper. And how temperature influences the performance of the motor is presented. Through analysis, how to calculate the motor end leakage is obtained. Simple method of mechanical loss http://www.999magnet.com/products/142-neodymium-prices is gained by traditional experiential calculation formula. In this paper, how to select and arrange permanent magnets are discussed. Moreover, The MATLAB is used to program and design the prototype. And, the computer simulation results, such as wave shape of air-gap magnetic field and wave shape of no-load back electromotive force are shown by ANSOFT according to its model. Besides, the isolated magnetic bridge width influences on the motor performance parameters are given. Experiment data approves that the prototype has high performance. The prototype efficiency is higher 12.4% than induction submersible motor’s for screw pump. And, the maximum torque multiple of the prototype increases to 2.42 from 1.67 of original induction motor. Contrasting experiment data and design calculation results show that the method and program developed in this paper are correct and feasible convenient in use as well. The research work in this paper is very important to improve the design method of permanent magnet synchronous motor.

Researches on Behavior of Vibration and Noise in Axial Flux Permanent Magnet Motor

　　Researches on Behavior of Vibration and Noise in Axial Flux Permanent Magnet Motor
　　Researches on behavior of vibration and noise in axial flux permanent magnet motor are conducted in this dissertation. The main research contents are as follows.Firstly, axial fluctuating electromagnetic forces caused by various harmonic magnetic fields in air gap are analyzed and calculated for 5kW axial flux permanent magnet motor for boat.
　　Because the axial electromagnetic force created on stator teeth in air gap magnetic field is the main reason for electromagnetic noise and vibration in axial flux permanent magnet motor, axial magnetic flux densities are extracted in electromagnetic field analysis. rubber magnetic sheet The axial electromagnetic forces in the air gap are calculated by Maxwell stress tensor method and the harmonics of the force density are also analyzed. Distribution of 3-D magnetic density of axial flux permanent magnet motor is obtained by calculating 3-D magnetic field. It shows that magnetic flux density waveform in the air gap relates to magnet configuration, current harmonics, wound distribution, the number and formation of tooth slot of stator and power angle. The principle resulting in axial electromagnetic force in axial flux permanent magnet motor is deduced by numerical algorithm.Secondly, according to loading condition obtained by analysis of electromagnetic field, the structure transient response of axial flux permanent magnet motor is analyzed. The axial electromagnetic force acting on stator tooth obtained by calculation of motion electromagnetic field is applied to 3-D model of axial flux permanent magnet http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php motor. The displacement response of all nodes is obtained by transient analysis of 3-D structure for the motor. Modal analysis in structure of electrical motor is an important method to determine whether the resonance of the structure can be induced under axial electromagnetic force. Some modal frequencies and shapes of 5kW axial flux permanent magnet motor are calculated by 3-D finite element method. The improved scheme is presented in structure of the motor.From experimental investigation of axial flux permanent magnet motor, the relationship between axial electromagnetic force and vibration modal frequencies is examined, and the relationship between axial electromagnetic force and electromagnetic noise frequencies is determined, too. It, theoretically and experimentally, draws the conclusion that the axial electromagnetic force frequency is a main factor affecting upon sound radiation of axial flux permanent magnet motor.

Research on Vibration Fault Diagnosis System of Rare-Earth Permanent Magnet Machines

　　Research on Vibration Fault Diagnosis System of Rare-Earth Permanent Magnet Machines
　　Rare-earth permanent magnet machines are used in the production of industry and agriculture no more than 30 years. It played a great role in national production, People pay more and more attention on it, but there is little research to make on fault diagnosis of rare-earth permanent magnet machines, so it is more meaningful to do a work on vibration fault diagnosis system of rare-earth permanent magnet machines.Permanent magnet machines use permanent magnet Block neodymium magnet for exciting instead of electric excitation, so there is no such fault as broken rotor bar, winding short circuit, casting defects produced by large current or overload. For this there more reliable in permanent magnet machines, but there still has fault in stator such as inter-turn short circuit, layer short circuit, phase to phase short circuit and stator loosening. In this paper has been analyzed electromagnetic force wave of permanent magnet synchronous motor when it is working, and obtained the vibration characteristics of unbalance stator, paper also concluded main machinery vibration faults’ characteristic.On fault signal processing, multi-resolution analysis (MRA) based on wavelet analysis theory is put in forward in this paper to decompose fault signal from high to low frequency.
　　The fast wavelet algorithm-Mallat pyramidal algorithm is realized by VB program and applied it to do multilevel wavelet decomposition, then compare signal processing results with FFT analysis, it proved that wavelet analysis is better than Fourier analysis in processing multilevel frequency and transient signal.Paper use improved BP neural network algorithm which http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php theory has been fully developed and more practical to identify faults. Applied momentum BP algorithm to resolve norm BP neural network algorithm has long training time and easily fall into minimization by sample data normalization and increasing momentum factor. Combined with fault character frequency of permanent magnet synchronous motor defined input sample and output goal data. Paper identified faults by 3-layer network and optimized the number of middle layer and learning rate. Training results prove that optimized network has improved in convergence speed. Testing training results by input new fault sample show that it can identify fault sample pattern.Paper use VB program to create a diagnosis system based on wavelet analysis and BP neural network algorithm, basis on ISO2372 standards classified equipment. Applied system to analyzing 55kW rare-earth permanent magnet machines used in pumping unit, proved that wavelet analysis is suit to analyzing fault signal and the results of BP diagnosis is consistent with fact.

The Research and Design of Nested Permanent Magnet Magic Ring

　　The Research and Design of Nested Permanent Magnet Magic Ring
　　There is a kind of special permanent magnetic mechanism—nested permanent magnet magic ring which is composed of two concentric magic rings, each of them is made up of permanent magnet segments with different magnetization directions. The magnetic conductivity of permanent-magnet material approaches to the air, so the magnetic field produced by the outer ring may pass through the inner ring free, and the central magnetic field is a vector superimposition of two magnetic Ball Neodymium Magnets fields. If we design the magic ring properly, a magnetic flux density level several times as much as the remanence of permanent magnet material can be achieved, and realized continuously to change from zero to the maximum value by the synchronized contra-rotation of the inner ring and the outer ring.It is complicated of the structure and the work process of nested magic ring, the inner ring must withstand certain degree degaussing field function of the outer ring. The permanent magnet blocks interact with the move of their position, and abnormal magnetization including local saturation, local demagnetization and rotational magnetization easily emerge. The work point of magnetic field might achieve arbitrary quadrant of hysteresis loop, so the ideal nested magic ring is unable to work normally under the theory value. Though some foreign researchers produced some nested magic ring mechanisms, they are not http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php comprehensively simulates the magnetic field distribution and the magnetization condition in the assembly and the work process, and the value of magnetic field is low.Based on analysis of basic structure and work process, one kind of improved nested magic ring is proposed. The material of the inner ring has a higher coercive force, and the outer ring has a bigger remanence. The improvement nested magic ring not only may have bigger field intensity under a smaller volume, but also better reduce the magnetic field component of x axis.Combining the vector Preisach hysteresis model and finite element analysis, a dynamic magnetic field analysis is implemented for nested magic ring in the process of assembling and working. Through adding the certain shape of the soft magnetic material or the permanent-magnet material in the center air gap, two kind of special enhanced nested magic ring are designed. It may choose the appropriate structure according to different needs.

Research on the Application of Modern Quality Management in Permanent Magnet Motor Manufacture

　　Research on the Application of Modern Quality Management in Permanent Magnet Motor Manufacture
　　The quality of products is an important flag to symbolize the developing level of the productivity, technology and economics in a country. With the advancement of the society and the development of science and technology, the requirement to the manufacturing quality of products become higher and higher. In our country, the technique of researching and developing is gradually mature in permanent magnet motor and it is applied widely. However, in the manufacture process, neodymium magnets there are many quality problems, such as, the insufficient stability judgment of manufacture process, the big fluctuation of stator quality and the low employee quality consciousness. How to raise the permanent magnet motor manufacture quality, reduce cost, and advance employee quality consciousness, it is already the key that electric motor manufacturing enterprise exists in sustained changeful environment.
　　On the base of reviewing the relevant status quo’s researches, the paper firstly reviews the history of the three developing stages of Quality Inspection, Statistic Quality Control and Total Quality Management, sums up the basic ideas of quality management and it impetus to launch of quality assurance activities, and analyzes the main work and harvest to implement modern quality management in our country. Basis on analyzing the reason of product management variation and the introduction of common quality control methods, some key problems about statistical quality control are elaborately discussed, developing a method for deciding the quality control line, setting up a mathematical model that based on the sampling plan of multi-variation of product quality. The limitation of 3σcriterion in traditional statistical quality control is analyzes, the concept of 6σcriterion in modern quality control is introduced, and the DMAIC implementing method is elaborately expatiated. In the analyzing http://www.chinamagnets.biz of example, the quality condition of transverse flux permanent magnet motor in manufacture process is analyzing, finding out questions. Continuous improvement is used to resolve the problem of complex process in stator manufacturing, the theory of fuzzy diagnosis is applied to discriminate the manufacture process condition of permanent magnet material quality control chart, stator mangling reasons are analyzes, and applies some improvement proposals. It have made the permanent magnet motor manufacture quality notable rise, prevented the hidden trouble of quality, and cut down the unnecessary dissipationThe main body of this paper research work can enrich the research so far to the manufacture process quality of permanent magnet motor, especially base on the combination of quantitative and qualitative method, analyzing the problem of permanent magnet motor in manufacture process, it is the perfecting and complement to present manufacture management method of permanent magnet motor. Though it researches on the permanent magnet motor, the method and idea analyzing problems, solving problems have certain references significance for our electric motor manufacturing enterprise, even for production manufacture enterprise in quality management.

Temperature Calculation and Cooling System Design of Permanent-Magnet Electric Motors

　　Temperature Calculation and Cooling System Design of Permanent-Magnet Electric Motors
　　The performance targets of permanent-magnet electric motors are prominent,compared to other type electric motors.Permanent-magnet electric motors will be applied every industry widely.Because the developing tendencies of permanent-magnet electric motors are high-capacity , high-power density and small volume . It makes divergences between the temperature rise and other performance targets of permanent-magnet electric motors. In order to solve these Ball Neodymium Magnets problems,it must design the cooling system properly and calculate temperature. The temperature rise of permanent-magnet electric motors not only considerate the stator winding but also permanent magnetism at the same time.The thesis descrips the temperature calculation and the cooling system design as follows:
　　First,the thesis analyzes the thermal field according to electromagnetics,heating, fluid and so on. It calculates and analyzes the temperature field of radial permanent-magnet electric motors.Making use of the equivalent thermal network model,meshing the finite-element,centralizing the parameter ,listing a set of conventional semi-empirical equations and solving the temperature of each nodes. When it ascertains that the medium in electric motors and heat-transfer coefficient of related components,it will respond to the experience formulas.Second,from the quality,it explains the loss distribution for the radiul electric motors and makes differences between slot inner winding loss and http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php end-winding loss.From the theory,it makes analyses between stator yoke loss and stator teeth loss to decrease the errors.The thesis makes use of ANSYS,ANSOFT softwares,takes advantage of the finite-element method to analyse the thermal field of permanent-magnet electric motors,with steady and transient stage.At last, it makes analyses TYJS electric motor with machine tools.The results are satisficated between calculated and measured temperatures.At last,it analyzes the thermal field of a disk electric motor , which 5kW-450 two stator and single rotor .Because of the differences between radial electric motor and disk electric motor.Explain the loss distribution,heat-transfer coefficient and so on respectively for disk electric motors and radiul electric motors.The cooling system design of disk electric motor uses assumption coefficient, deduces fan structure ,designs the cooling system of the electric motor rationally .According to those,it may calculate the temperature of the electric motor ,and reache the maximum. It is convenient to improve and develop the prototype.

Study on Surface-magnetic Permanent Magnet Propulsion Machines

　　Study on Surface-magnetic Permanent Magnet Propulsion Machines
　　This report introduces briefly present research status and the development trend of permanent magnet propulsion electrical machines in many countries, the basic techniques demands of research is put forward, this is the design example with the basic parameters of Siemens PERMASYN permanent magnet propulsion machines to finish research plan. It is brief introduced about NdFeB permanent-magnet material and SmCo permanent-magnet material. It is discussed and analyzed in this report about the effect of armature response characteristic with surface and tangential magnetic circuit structures in permanent magnet propulsion motor. A new structure model with surface Permanent magnet case is put forward, that is a renewable surface permanent magnet cases with a pole-shoe. It is chiefly Samarium Cobalt Magnets introduced in this report that a rotor damping winding design and its influence, analysis and calculation of surface-magnetic circuit structure in permanent magnet propulsion electrical machines. Sub-Transient Reactance and Exchange Phase Inductance formulas are deduced, Mathematical models for this new structure model with surface magnetic circuit structure is chalked up. It is discussed and analyzed a concentrative fully pitched winding (q=1) and a fractional-slot winding (q =3/10) characteristic in permanent magnet propulsion electrical machines. Through finite element method use of ANASYS software is used to analyze different machine configuration, for example, 18-phase、24-pole fully pitched winding and 18-phase、40-pole fractional-slot winding. It is shown that the proposed permanent http://www.chinamagnets.biz/Samarium%20Cobalt/Samarium-Cobalt-Magnets.php

 magnet propulsion electrical machine with fractional-slot winding has a low torque pulsation clearly. It is simply introduced in this report that the current source models main circuit topology construction, the operation principle drawing of main circuit about six channel parallel connection in this research plan is put forward ,and introduced in this report that the DCVC、the Restrain Pulse Reactor、the ACI and it’s operation principle.New point of views and new developing ideas are put forward about the large power permanent magnet propulsion electrical machines in this studied. It has realizable and good engineering realistic condition.

Study on Sensorless Control of PMSM Based on the Theory of Extended Kalman Filter

　　Study on Sensorless Control of PMSM Based on the Theory of Extended Kalman Filter
　　With the widely use of permanent-magnet synchronous motor in many fields, the study on the permanent-magnet synchronous motor, a kind of inevitable development trend, has real meaning and value.Permanent-magnet synchronous motor (PMSM)is attractive for high performance drive systems because of its high efficiency and suitability for wide speed ranges of constant power operation. Mechanical sensors , limit the low speed operation of the machine, and is Block Neodymium magnets sensitive to the estimation of parameters, such as stator inductance and resistance.The demand of high performance and reliable drive system now pushes research toward the elimination of mechanical sensors. Recently, sensorless position control of motor is a challenge. There have been numerous publications on methods to eliminate the position sensor on motorsin the last several years.Based on the theory of nonlinear estimation, we researched on the sensorless control of PMSM. The thesis illustrates the principle of the (EKF) and it’s application in the system, establishes the simulation model of the vector control system of PMSM based on the EKF and successfully realizes the application of the speedless sensor in motor control. Firstly, based on the mathematic model of permanent-magnet synchronous motor, the PMSM vector control system is built. Secondly, the Extended Kalman Filter is http://www.999magnet.com designed for the on-line estimation of the speed and rotor position by only using measurements of the motor voltages and currents. And then, with matlab7.0 software, the reasonability and validity of the EKF programmer in the motor control have been testified by the simulation results, which show the effectiveness of the system and the methods. At last, the improved method is proposed according to the decination of the results of the simulation.

Study on PMSM Main-Spindle Direct Drive System

　　Study on PMSM Main-Spindle Direct Drive System
　　In the field of industry, numerical control machine tool and manufacture center are the important equipments of mechanical manufacturing. In order to increase machining precise, performance improvements for main-spindle direct drive system are studied deeply. Among them, it is an important research that how to apply permanent magnetic synchronous motor (PMSM) system into direct main-spindle drives. The work of this thesis is approached based on the cooperative project“Study and Manufacture of main-spindle AC Drives System”of Harbin Institute of Technology and Qiqihar neodymium magnets Machine Tool Electrical Apparatus Factory. The prospective object of the project is to develop wide range speed regulation, high performance and Full-digital PMSM AC servo system for direct main-spindle drive.In order to implement direct main-spindle drive, some key technique problems such as system model and control method, were studied deeply in the thesis. Firstly, many domestic and overseas correlative documents were consulted for knowing the development status of main-spindle drive system full-scale. The mathematic model of PMSM was deduced for theory analysis and simulation. Control method was studied in order to improve the performance of main-spindle direct drive system. System hardware circuit and software program were designed. At the end, the experiment and simulation http://www.chinamagnets.biz were done.In the part of principle analysis and modeling, the mathematical model of PMSM was deduced according to the configuration of PMSM. The parameters of prototype were measured and were applied to simulation. And according to the mathematical model, vector control principle and minimal direct axis current control and its digital realized method were discussed.In the third part of the papers, four factors that affect the performance of PMSM running at low-speed were analyzed and the promoted schemes for the factors were designed. The dead-time effect on SVPWM inverters and the low-speed characteristic of the PMSM servo system were analyzed. In addition, a novel method of dead-time compensation based on SVPWM was proposed in the paper. The results verify this method has a good compensation effect.

Research and Development on Servo Control System for PMSM Based on DSP

　　Research and Development on Servo Control System for PMSM Based on DSP
　　Servo control technology is one of the most important parts of mechatronics, which is widely used on the automatic equipments, such as CNC and industrial robot. AC servo system has advantage over DC servo system, so it has very important significance to study on high performance and reliability of AC servo control system.In this paper, the development of servo system is first given, and then, its classification, current situation and development trend are summarized. neodymium magnets On the basis of discussing the composition and operating principle of PMSM, its mathematical model is built in quadrature-direct axis coordinate system according to the rotor field oriented theory. Then, several realization methods of vector control for PMSM are analyzed, and the method of direct axis current equaling to zero is chosen. On the premise of studying SVPWM technology and adaptive backstepping control technology, the simulation models of servo control system for PMSM are built in Matlab7.1/Simulink to discuss their correctness and validity.With the self-designed power stage board for PMSM and a ready-made Freescale DSP56F8346 control board, the hardware system for PMSM servo http://www.999magnet.com control is constructed. The design of some major hardware circuits for the inverter, voltage/current sensing, protection, position/speed sensing, brake control etc, are introduced in the paper.The corresponding algorithms for PMSM servo control are proposed and coded in DSP by using CodeWarrior IDE to complete the software design. Experiments are conducted on the PMSM servo control system, and the experimental results further prove that the control model and strategy for PMSM servo control system are reasonable and effective.Finally, a summary of the research work is presented, and the further work prospect of this subject is given.

The Position Sensorless Control for PM Brushless DC Motor Based on WNN

　　The Position Sensorless Control for PM Brushless DC Motor Based on WNN
　　Permanent Magnet Brushless DC Motor (BLDCM) has many advantages such as simple structure, reliable, easy maintenance, high operating efficiency and good timing performance, so it is widely used in various fields of national production. Generally, the commutating signal of BLDCM could be got from rotor position sensors. But the existence of rotor position sensors increases the Ball Neodymium Magnets motor’s size, costs and reduces its operational reliability. Therefore, it has important value in theoretical and practical to study position sensorless control methods for BLDCM.To get commutating signals from some signals of the motor without position sensor can be regarded as a nonlinear system identification process, and be solved by the identification methods.
　　Artificial Neural Networks (ANN) now has become an excellent nonlinear system identification method for its advantages, such as approach ability, good compute ability and robust. Because Wavelet Neural Networks (WNN) has the merits of fast, accuracy and global convergence, which ANN or Wavelet possesses, it has great potential in nonlinear system identification.This paper concentrates on position sensorless control for BLDCM, proposes a novel control method that used WNN. Firstly, the principle of position sensorless control for BLDCM and some control methods are analyzed in detail. Then the relationship between rotor’s position and phase voltages of BLDCM is analyzed, and the direct voltage control method based on WNN for BLDCM without http://www.chinamagnets.biz position sensor is subsequently proposed. Adaptive algorithm is used in this paper to choose the number of WNN’s hidden units, and the WNN is finally built with a much simpler and tighter structure. Thus enhances the real-time character of networks, and avoids the tendency of unconvergence and mess calculation caused by improper hidden units’number. The parameters of network are initialized by offline training in this paper, while the weights of WNN are updated by online learning. Thus, the approach ability and adaptive capacity are both ensured. At last, the method of direct voltage control based on WNN for BLDCM without position sensor is confirmed by simulation. A control system for BLDCM is designed in this paper based on TMS320F2812, and the method proposed in this paper is experiment on this system. The experimental results show that this method can provide an accurate commutating signal for BLDCM, and is proved to be highly accurate, good self-adaptable, fast dynamic responsibility and robust.

Robust Velocity Control System of Linear Permanent Synchronous Motor

　　Robust Velocity Control System of Linear Permanent Synchronous Motor
　　Along with power electronics, micro-processor, micro-electronics, rare earth permanent magnetic materials and modern control theory, permanent magnetic synchronous motor (PMSM) has been widely in motion control of medium and low capacity both in industry and daily living. Besides, it seems to expect trend its taking place of DC motor and asynchronous motor for Block Neodymium magnets velocity control gradually. Meanwhile, conventional lathe has intermediate conversion segments transporting rotating motor into linear motor, which confine precision. Linear permanent magnetic synchronous motor (LPMSM) has ability to move linearly without intermediate conversion segments and conquers the inherent defect.In this paper, the research object is the velocity controller of the linear permanent magnetic motor. First design considerations and work principle are introduced, http://www.999magnet.com and motion equations are listed. Then, space vector modulation is presented and robust velocity controller is designed based on theory of robusticity. After that, the system is simulated on the platform of MATLAB. Finally, hardware based on DSP TMS240LF2407 and software are designed, and some experiment are complete.

Researches on a Transverse Flux Permanent Propulsion Motor Control System

　　Researches on a Transverse Flux Permanent Propulsion Motor Control System
　　The development of the integrated electric power system (IPS) has brought higher request to propulsion motors. Ships are limited by internal space, and therefore, research aimed at developing compact direct drive propulsion motors is becoming a hot spot. A novel machine-transverse flux permanent magnetic (TFPM) motor is proposed in order to improve torque density of Segment neodymium magnets the motor, which obtains more and more attention these years.In this thesis, based on the TFPM motor features, a mathematical model of TFPM motor is given, a novel direct torque control (DTC) method for TFPM motor is proposed with the control scheme. In the implementation of the DTC method, two hysteresis comparators are used to control the magnetic flux and torque, and the switching of the inverter is decided by a optimized switching table. After, a simulation model of the DTC control system is created in SIMULINK. Simulation results verify the proposed strategy is effective for TFPM motor control.The proposed system has been implemented and carried out on a power electronics http://www.999magnet.com development platform based on TMS320F2812. IPM and DSP is the core of the hardware platform, the converter topology is the typical AC-DC-AC structure, phase current, DC link voltage and rotor position are measured by hall sensor or encoder, and transferred to the DSP’s AD channel or QEP unit respectively. The control algorithm is achieved in the DSP programmed by C. The experiment results are given and agree with the simulation result very well.Simulation and experiment results show the TFPM motor control characteristics as: quick response, easy implementation and good robustness, so direct torque control is effective to imply on TFPM motors.

Study on the Rare Earth Permanent Magnet Synchronous Motor by FEM

　　Study on the Rare Earth Permanent Magnet Synchronous Motor by FEM
　　This dissertation develops partial contents of national 863 projects "The High Speed Highly Effective Explosion-proof Rare Earth Permanent Magnet Synchronous Motor". In order to improve the efficiency of rare earth permanent magnet synchronous motor (REPMSM), the paper combined FEM (Finite Element Method) with experiment methods, and studied on the Neodymium Magnets copper losses of rotor of REPMSM in the steady-state, the starting process simulation of REPMSM, and the harmonic in air-gap magnetic field at no-load of REPMSM.The paper has calculated accurately a 22kW REPMSM in oil field for pumping with the FEM software MagNet. At the fist time, the copper losses of rotor in the steady-state of REPMSM because of the harmonic analyzed thoroughly, the direct and indirect method to measure the efficiency of the 22kW REPMSM is disposed for the harmonic losses. Compared the simulation and experiment result, the copper losses of rotor in steady-state of REPMSM existed actually. The idea is different from the traditional theory of REPMSM in the steady-state.The starting process simulation for the 22kW of the REPMSM with the FEM software http://www.999magnet.com of the MagNet is searched deeply. And the starting process experiment at no-load is completed, the measurement result proved the exactness of the simulation results. Simultaneously, the simulation result by the MagNet provided the reference to optimize REPMSM.The air-gap magnetic field at no-load of 370W REPMSM has simulated by the FEM software MagNet, the simulation results of THD (Total Harmonic Distortion) of back electromotive force at no-load was 6.23%. In order to prove the result of simulation, two 370W REPMSM had towed each other, the measurement results of THD was 3.26%.The damping effect to air gap harmonic was found by the rotor squirrel-cage bar.

Study on the Key Technique in Design of Permanent Magnet Synchronous Motor for Metro

　　Study on the Key Technique in Design of Permanent Magnet Synchronous Motor for Metro
　　The thesis is devoted to exploiting study on the key technique in design of permanent magnet synchronous motor (PMSM) for metro. Three parts are included as follows:At first, the leakage coefficient of PMSM is accurately calculated by three-dimension finite neodymium magnets element method (FEM). The leakage coefficient of PMSM is analyzed with factors change such as rotor structure, permanent magnet size, air-gap length and magnetic bridge size, and summarized the rule of leakage coefficient with structural parameter change. Which is useful for the rotor structure choice of PMSM for metro, as well as the leakage coefficient selection in electromagnetic calculation.ANSOFT is used to calculate the reactance parameters of PMSM in the second part. On the basis of the reactance parameters calculations of many permanent magnet synchronous motors, the change law and influencing factor of the reactance parameters with different rotor structure are analyzed, and the rule of the reactance parameters of PMSM is given.
　　Which is good for selecting appropriate rotor structure, as well as enhancing the characteristics of motor.At last, the research work of PMSM for http://www.chinamagnets.biz metro is carried out. The influence of motor type to the thermal load and the effective material peak-value power density is analyzed, and the dimensions of the motor are selected. The influence of different rotor structure to the reluctance torque is analyzed, and given the selection principle of the rotor structure. The influence of air-gap length to the permanent magnet quantity and the togging torque is analyzed, and given the select principle of air-gap length. The requirement for leakage reactance on stator of PMSM supplied by voltage type inverter is analyzed, and some parameters are selected, such as electromagnetic load, slots shape of stator and so on. The common method of enhancing the efficiency is given, such as decreasing the iron loss, copper loss and machine loss. Given some cautions on how to decrease the noise and vibration. From above all, a PMSM for metro isdesigned by field-circuit coupled method, and then the motor is analyzed and calculated by ANSOFT.

Studys of the Sm3(Fe,M)29Nx/α-Fe(M=Cr,V) Nanocomposite Permanent Magnetic Materials Prepared by Melt-Spun

　　Studys of the Sm3(Fe,M)29Nx/α-Fe(M=Cr,V) Nanocomposite Permanent Magnetic Materials Prepared by Melt-Spun
　　After the apearance of the nanocomposite permanet magnetic materials, with it’s perfect internal magnetism, it initiate a new power for the research of magnetic materials. The permanent magnetism is beyond the NdFeB, and the Curie temperature increased greatly, which provide optimistic foreground for the permanent materials. The amorphous band was Segment neodymium magnets perpared using the melt-spun method, and Sm3(Fe,M)29Nx/α-Fe (M=Cr,V) powders were carried out through the processing of crystalization and nitrification etc. The pocessing> detection and analysis method for Sm3(Fe,M)29Nx/α-Fe (M=Cr,V) magnetic materials were stuied detailedly. Adopting advanced detection method, author analysizes the microstructure and magnetic performance. The effect of addition element on microstructure and magnetic performance were stuied basically.The http://www.999magnet.com minor elements were added befittingly, while the atom rate of addition element is below the 3.3% such as Sm3(Fe26.5Cr2V0.5)> Sm3(Fe26Cr2V1), the minor elements were steady in Sm3(Fe, M)29 phase and the rate of Sm3(Fe, M)29 and α-Fe was perfect. So the homogeneous amorphous made out by the melt spun, then the unanimous amorphous alloy was carried out. The uniform grain was fabricated out by crystalization. We got an advanced magnetic performance far-beyond the alloy in other component. When the atom rate of addition element is beyond the 3.3% as Sm3(Fe25.5Cr2V1.5) 、 Sm3(Fe25Cr2V2), the added elements enhance α-Fe phase consumingly, and debase the liquidity acutely, thus depress the magnetic performace.

Research of the Three-Dimensional Magnetic Field Distribution Around a Rectangular Permanent Magnet

　　Research of the Three-Dimensional Magnetic Field Distribution Around a Rectangular Permanent Magnet
　　With increasing application of magnets in the magnetic levitation, the comprehensive understanding of the three-dimensional magnetic field becomes more important. Surrounding the special magnetic field distribution of the rectangular magnet, series research of fundamental experiments, theoretical analysis and computing simulations were presented.For the magnetostatic Ball Neodymium Magnets solution of a rectangular magnets’magnetic field, the accurate analytical calculation was chosen. Based on Ampere’s molecular current hypothesis, the analytical model for rectangular magnet with only one magnetization direction was established. And the integral equation formulation for magnetic field of a rectangular magnet was obtained. It was indicated that the thickness of the magnet play more important role in effecting the magnetic field than the length and the width, and the strong magnetic filed in the magnetization direction was thin 53 times the width and 21times the thickness. According to the analytical solution for single magnet, the formulation for repulsive and attractive magnets was acquired. The effects of different magnet arrangements were described.
　　The field analysis results were confirmed with the experimental results and other theoretical expressions including dipole magnet theory and scalar potential model.The three-dimensional magnetic field distribution for both single magnet and repulsive and attractive magnets was obtained from fundamental experiments performed mainly for single magnet and double magnets. http://www.chinamagnets.biz It was shown that the magnetic field distribution longitudinal the magnetization direction was centrosymmetric and the one perpendicular the magnetization direction was anti- centrosymmetric. The characteristic of magnetic field distribution graph and the interaction between two magnets were described. The distribution shape of Hz, namely the magnetic field distribution longitudinal the magnetization direction, for different distances was presented.The three-dimensional simulations for many magnets’magnetic field based on the equation formulation of single magnet were performed. Two arranging manners were considered and the effect of gap between magnets was analyzed. The results showed that the wide constant magnetic field can be acquired by using many rectangular magnets, but the gap resulted in fluctuation that would cause negative effect to the control of magnetic field.

Optimization Design of Permanent Magnetic Mechanism in High Magnetic Field

　　Optimization Design of Permanent Magnetic Mechanism in High Magnetic Field
　　The permanent magnets with high field intensity are used in medical systems, military affair and high-energy physics fields. They are usually electromagnets or superconductor magnets at present. If we design the size of the permanent magnetic mechanism properly, there will be much higher magnetic field than its remanence in the center, and it can replace the superconductor magnet and electromagnet. So with the development of properties about permanent magnetic material, the Ball Neodymium Magnets optimization design of the permanent magnetic mechanism with high magnetic field must develop well in the future in the magnetic field.There is a kind of special permanent magnetic mechanism--permanent magic ring which is made up of permanent magnet blocks. Their magnetized direction changes equably.
　　In the assembly complex process, the permanent magnet blocks with different magnetized direction will impact each other, and might bring the local demagnetization or saturation. So the work point of permanent magnetic material might be at the whole hysteresis loop including minor hysteresis loop. The traditional method only considers the demagnetized curve of the magnetic material, so inevitably there are some errors in simulating the magnetic characteristic in the high magnetic field.This paper presents two optimization schemes .They both introduce the soft magnetic material into http://www.chinamagnets.biz permanent magic ring to reduce the effect of the demagnetization and the saturation. Programs made by Fortran Language combine a genetic algorithm with a finite element analysis and a Preisach hysteresis model. Basing on the simulating the actual properties of permanent material, the aim of optimization is to obtain the highest average density of magnetic flux in its center after the magnetic ring assembly. The optimized result is the size of the soft magnetic material in the schemes. The optimized results. are reasonable through the experiments of the traditional simplified method such as current sheet.The length of magic ring is designed by Ansoft Maxwell considering both the product cost and the intensity of magnetic field. The initial fixing position can be designed by the analysis of magnetic force at each step in fixing by Ansoft Maxwell. And they present important parameters for the tools used to fixing the permanent magic ring.

Vector Control System of Permanent Magnet Synchronous Motor Based on Input Current Space Vector-Output Hysteresis Current Control Modulated Matrix Converter

　　Vector Control System of Permanent Magnet Synchronous Motor Based on Input Current Space Vector-Output Hysteresis Current Control Modulated Matrix Converter
　　Permanent magnet synchronous motor is small in size, light weight, low inertia, high efficiency, the rotor without heating characteristics. Once there it will in high-performance servo system has been widely applied, such as industrial robots, CNC machine tools, flexible manufacturing systems, various automation equipment, and other fields. The evolution of vector neodymium magnets control technology has enabled PMSM to possess as good performance as that of DC motors and become the preference of modern drive systems. Also AC-AC matrix converters hold good potentialities in AC drive systems owing to its unity power factor, without bulky capacitors, and sinusoidal input currents.
　　Therefore, the combination of the PMSM vector control and the matrix converter has recently arrested substantial attentions from scholars both at home and abroad.The present paper presents the research on the vector control system of matrix converter-permanent magnet synchronous motor (MC-PMSM) based on input current space vector-output hysteresis current modulation, and introduce theoretical analyses and simulation research about the implementation method, the input current quality and the speed regulating performance of the system. The MC-PMSM system prototype is designed and implemented, in which the digital signal processor (DSP) and the complicated programmable logic device (CPLD) act as the control units. Then experiments are also performed.Main http://www.chinamagnets.biz contents concerned in the paper are as follows:The switch state combinations of MC-PMSM vector control system, which is based on the input current space vector-output hysteresis current modulation, are analyzed at full length, providing basis for the designing of the control system.The modle of MC-PMSM vcotor control system which based on the input current space vector-output hysteresis current modulation is build, and then the simulation and analysis are taken.Finally, the platform of the MC-PMSM vector control system is constructed in the present research on which the correctness and feasibility of the methods provided in the paper are verified, highlighting the significance of the present research for further researches.

Modeling and Maximum Power Point Tracking (MPPT) Control of Direct-driven Permanent Magnet Synchronous Generator (D-PMSG)

　　Modeling and Maximum Power Point Tracking (MPPT) Control of Direct-driven Permanent Magnet Synchronous Generator (D-PMSG)
　　Nowadays,the low-speed Direct-driven Permanent Magnet Synchronous Generator (D-PMSG) grid-connected wind turbine becomes one of the hotspots of wind power generation technique research. On the basis of the contrast existing four kind of common wind-power system structure and performance’s, This paper will establish completely mathematical model of low speed Alnico magnets D-PMSG system, and conducts the research to its high efficiency variable current electric circuit’s topology structure and its power optimum control strategy.At first ,this paper introduces the work principle, subassemblies,performance and sorts of grid-connected wind turbine. Then, it compares the existing four categories VSCF wind generator systems of various kinds of structural characteristics, advantages and disadvantages, and then that low-speed permanent magnet synchronous generator directly wind-driven generators superiority. And concludes that the direct-driven PMSG wind turbine is the best choice. On the base of comparing five kind of wind-driven generator system structure and four type variable current electric circuit topology applied in it in briefly,
　　This paper advances a main circuit which is based on IGBT’s power grade nowadays and In operating performance situation, which is applied in high power direct-driven grid-connected wind turbine. It is made up of a three-phase rectifier, two paralleled BOOST chopper circuits and one PWM inverter. This paper analyzes their work principle and obtains the mathematical model of this kind of system structure in the summary to the existing system model’s foundation. http://www.999magnet.com For the confirmation model’s reliability, the article chooses 1.2MW D-PMSG system, tests its performance and the frequency conversion performance under its rated condition, and has confirmed the modeling reliability and the accuracy through the simulation.After completed low-speed D-PMSG system mathematical model, the article summarized the D-PMSG ’s characteristic and the low speed frequency conversion characteristic, in accordance with the operation of D-PMSG Maximum Power Point Tracking(MPPT)control objectives and requirements, used the artificial neural network (ANN) controller for the variable pitch system and power feedback PI control to this kind of syetem. And carries on the simulation in the conditions of common gradual wind and random wind conditions separately in the Matlab simulation software, the simulation result indicated that the reliability and accuracy of timeliness with the artificial neural network (ANN) controller for the D-PMSG system.

Research on Automatic Measuring of Permanent Magnetic Synchronous Servo Motor

　　Research on Automatic Measuring of Permanent Magnetic Synchronous Servo Motor
　　These days, automatic measuring system has new approach for the computers a great deal application. Improving the precision and speed of motor test, carrying motor identity testing and adopting new testing method becomes feasibility because of the technique of electron developed rapidly in latter-day. In the developing background, the paper carries through the research Block Neodymium magnets of the motor automatic measuring and its control system.The main content of this paper is the software and hardware researching of Permanent Magnetic Synchronous Servo Motor(PMSM). This system is designed to measure motor’s three important parameters including stator coil inductance, stalling torque and back EMF. All of these test results are used as basis for product detect. According the analysis of current test methods of the three parameters, I have found that the normal test methods can not apply for automatic measurement additionally, the automatic measuring system are usually strictly kept in secrete as know-how by motor manufacturer, so the purpose of my paper is to develop a set of automatic system to measure those three methods for product detection.
　　This paper adopts PC and muti-fuction Data Acquisition Block (DAQ) as core controlling equipments, and other sensors relays as secondary equipments. The software of the automatic testing system. is developed Using LabVIEW to develop the system’s working platform and software, through ADO technique, combining SQL database and http://www.999magnet.com Excel digital table etc applied software to develop the printing system of data management, inquiring ,forms for reporting statistics and graph curved line.The paper first introduced the background of this project, then elaborate each parameter’test method. The testing system improved the testing precision, reduced the infection of the testing people, realized the auto computer control. On the other hand, the testing system can realize the auto manage to the testing data, draw characteristic curve automatically. The system has the characteristics of simple structure, satisfied accuracy and higher reliability.

Research of the Sm3(Fe, M)29Nx/α-Fe(M=Co,V,Mn) Nanocomposite Permanent Magnetic Materials by Melt-Spun

　　Research of the Sm3(Fe, M)29Nx/α-Fe(M=Co,V,Mn) Nanocomposite Permanent Magnetic Materials by Melt-Spun
　　The series of Sm-Fe-N nanocrystalline composite magnets has excellent intrinsic magnetic properties. Because of their high magnetic energy product of 1090kJ/m3 together with low rare earth concentration and high chemical stability, they are believed to be promising new candidates for applications in inexpensive bonded permanent magnets.In this thesis ,the Sm3(Fe, M)29Nx/a-Fe (M=Co , V, Mn) nanocomposite permanent magnetic materials with high performance have Ball Neodymium Magnets been obtained by crystallizing over-quenched ribbons. The effects of Fe content, the additions of Co, V and Mn on the microstructure of Sm-Fe alloys and magnetic properties of the ribbons with different composition are systematically studied.X -ray diffraction, scanning electronic microscope, transmission electronic microscope and vibrating-sample magnetometer were used to analysis the processing parameters of melt spun and crystallization treatment, microstructure and magnetic properties. The result of experiment indicated that: As the saturated vapor tension is lower than that of Fe, Sm volatilized firstly which is propitious to form Sm-Fe phase. In the later crystallization process, the http://www.chinamagnets.biz magnetic property of Sm-Fe alloys verify as the time and temperature of crystallization are changed. The condition of nitrogenation has a more notable effect on the magnetic property. If the time of nitrogenation is long enough, there are SmN and α-Fe phase in specimen of alloys. If the time of nitrogenation is too short, there is Sm-Fe phase of un-nitrogenation, the concentration of nitrogen is not of uniformity, and the concentration of nitrogen is far too low, all of above can result in decreasing of magnetic property. In order to obtain excellent magnetic property, our conclusion is that : When nitrogenation at 480 ℃,the optimal nitrogenation time is 6 hours.Besides, long-term ball milling deteriorated the magnetic properties. The reason is the oxidation of the power.

Research on Sliding Mode Control for Linear Permanent Magnetism Synchronous Motors Based on Neural Network Optimization

　　Research on Sliding Mode Control for Linear Permanent Magnetism Synchronous Motors Based on Neural Network Optimization
　　Sliding mode control has the characteristic of celerity, robust, and easy to implementation, but the chattering exists in the sliding mode. Neural network control strategy has the abilities of self-learning and adapt to the system uncertainties. For linear permanent magnetism synchronous servo motors (LPMSM), due to the cause of chattering, using the neural network-based compensation methods are proposed to optimize the sliding mode control and weaken the system chattering, Special shape NdFeB magnets  so that the system could rapidly and accurately track to the command signal. First, using the MATLAB/SIMULINK, a general simulation model of LPMSM controlled by SPWM vector current sluggish tracking is established with block diagram through the analysis and research of LPMSM and its vector control principles. Then the thesis introduce three methods of optimizing the sliding mode control by the neural network: a two-degree-freedom controller with neural network-sliding mode control, sliding mode controller’s celerity could keep the track capability of the system, and designing the feedback controller using neural network to restrain the influence of http://www.999magnet.com parameter variations and disturbance, and weaken the chattering. A sliding mode controller based on neural network observer, because the linear observer has weak adaptability to parameter variations, we designing a neural network observer parallels to linearobserver, then using the summation to come true compensate. A position tracking sliding mode controller based on RBF neural network compensation, using RBF neural network learning the uncertainties and disturbance, so that compensates real time and weaken the effect of chattering to system.At last, the simulation research result which based on the general simulation model of LPMSM, show the effectiveness of the control strategies that designed in this paper.

Design and Thermal Characteristic Research on High Speed Permanent Magnetic Synchronous Motorized Spindle

　　Design and Thermal Characteristic Research on High Speed Permanent Magnetic Synchronous Motorized Spindle　　
        High speed machining is a promising technology for significantly increasing productivity ratio and reducing production costs. Development of high-speed spindle technology is strategically critical to the implementation of HSM. Compared to conventional spindles, and motorized spindles are equipped with built-in motors for better power transmission and balance to achieve high-speed operation. The motorized spindle is equipped with a built-in motor, so that "zero transmission" is realized. It has simple structure, small power loss, small rotational inertia, fast response and easy to Neodymium Magnets achieve precise control of variable speed, but the motorized spindle used to adopt asynchronous induction motor which has large power loss, resulting in large heating, high temperature-rise and large thermal deformation of the motor spindle, then influence on the machining precision of high-speed machine tools seriously. In order to reduce the temperature-rise of motorized spindle and improve it’s thermal characteristic, we select PMS motor which has little calorific value, completing the overall structure designing of permanent magnetic synchronous motorized spindle.
　　Then analysis the thermal characteristic of motorized spindle deeply. Special details of the thesis are as follows:(1) Completed the overall structure design of motorized spindle. Calculate the interference between the spindle and the rotor, analysis the static stiffness of motorized spindle in FEM based on the software ANSYS.(2) Calculated the loss and fever of http://www.999magnet.com PMSM and the frictional heating of bearing in motorized spindle, study the influence of various factors on bearing’s frictional heating. Analysis the heat dissipation characteristics of internal spindle, water cooling system and oil-gas lubrication system. Then calculated the corresponding heat transfer coefficient.(3) Establish finite element model of high-speed spindle’s thermal analysis, analysis the temperature field and thermal deformation of motorized spindle in FEM based on the software ANSYS. Discuss the influence of various conditions on temperature rise of bearing and thermal deformation of spindle. Finally, comparison study the thermal characteristic of PMS motor spindle and asynchronous motor spindle.

Elevator with Gearless Permanent Magnet Synchronous Machine Speed Traction Control System Research Based on Neural Network

　　Elevator with Gearless Permanent Magnet Synchronous Machine Speed Traction Control System Research Based on Neural Network
　　Permanent Magnet Synchronous Motors (PMSM) are widely applied in different places depending on their several inherent advantages. The low-speed and high-torque PMSM traction system is better than other’s when used in elevator control system.The system strong magnets dynamic performances are affected by the nonlinear friction factors when elevator running in low speed. With deeply research on PMSM vector control, a traction system is proposed in this thesis that based on TMS320F2812 DSP.The nonlinearity characters of PMSM caused by static and dynamic friction are trouble to forecast and avoid, especially with PI regulator. A Neural Network controller based on BP is proposed in order to achieve better conform performances of elevator. The controller has simpler structure and control algorithms and can be realized online easily.In order to prove the effectiveness http://www.chinamagnets.biz of the control algorithm, a simulation is made with matlab/simulink. The simulation results show the better robust and the better static and dynamic performance comparing to the PID control. This method has a simple structure and control algorithms, and can be realized online easily.

Study on the Key Technique of Permanent Magnet Linear Synchronous Motor

　　Study on the Key Technique of Permanent Magnet Linear Synchronous Motor
　　Along with the demands of high and ultra-high speed, exactitude and ultra-exactitude in the development of numerical control machining technique, Permanent Magnet Linear Synchronous Motor (PMLSM) as direct drive in the field of precision positioning has had widely applications. Compared with the conventional rotary motor and scroll lever, the linear motor’s servo system has removed the bad effects which are caused by the mechanical gearing. Because neodymium magnets of structural speciality, it needs to improve the motor’s thrust and thrust density hardly during design process, and adopt any kinds of effective methods to reduce the thrust undulation of linear motor. Otherwise zero transmission will lose its originally expected meanings. This thesis’s works circumfuse study on the key technique of PMLSM, the main work including the following sections.Firstly, in order to reduce the volume and increase the thrust density of the motor, the present wide used multi-pole, fewer tooth structure and windings have been analyzed and studied. The paper presents a reasonable design of the structure and windings of PMLSM, and concludes the application of this kind of special windings in linear motor, moreover, extends this kind of windings to generalization.
　　The harmonic wave of back-EMF during non-load state of the motor has been analyzed too. And it’s proved this kind of winding has higher fundamental wave winding coefficients and lower harmonic wave content.Secondly, aims at the detent force brought by end effect and cogging effect of linear motor, the paper presents some optimal steps. With the method of using concentrated and fractional-slot windings combined with permeance modulation, the paper gives a phase-shifting modulation to the permeance wave between teeth and slots, this eliminates cogging force effectively. For the sake of reduce the end force brought by the special end effect of linear motor, the paper presents a method of optimizing elementary length to modulate the phase of permeance of two http://www.chinamagnets.biz ends, and optimizes the elementary length. On the basis of optimizing elementary length, the paper presents a method of face to face moving two modules to reduce the end force. And based on the above works, the wave plot of Detent Force between one pole distance has been given.At last, through the modules comparison of traditional windings and this kind of special windings, the paper proposes a kind of coefficients computing method of this special winding motor. After measuring the real non-load back-EMF and compared it with theoretical value, it’s found the error is less than 1%. The author also deduced electromagnetic power and thrust equation and so on. On the basis of discussing force angle characteristic, the paper deeply analyzes the effect to electromagnetic power and thrust caused by frequency, and analyzes the motor’s running characteristic of the state of vector controlling too. Furthermore, the author programmed the electromagnetic computing program, and analysis the motor during vector controlled state with finite element method. A new developed PMLSM is also given.

Research on Vector Control Servo System for Permanent Magnet Synchronous Motor

　　Research on Vector Control Servo System for Permanent Magnet Synchronous Motor
　　At present, permanent magnet synchronous motor (PMSM) servo system has gainedgeneral regard all around the world. Fully digital system has always been the goal topursue in the field of servo system and provided fundamental impetus to the researchwork done in this paper. DSP exhibits a superior functionality, high processing speedand reliable performance, and therefore Neodymium Magnets has a wide application prospect in the field ofservo system. In this paper, the MATLAB/SIMULINK module has been set up on thebase of PMSM vector control system, and the program flow of servo system has beendesigned according to the simulation. Then use the TMS320LF2407A as the control coreto set up digital PMSM servo system, which includes testing modules for phase http://www.999magnet.com currentsand rotor position and rotor speed, modulation of trigger pulse. Meanwhile the design ofhardware is particularly introduced. The experiment results are presented and analyzedin the last chapter. These works provide an idea for the industrial application of PMSMservo system.

AC Variable Frequency Speed-adjusting System of Permanent Magnet Synchronous Motor for Hybrid Electric Vehicle (HEV)

　　AC Variable Frequency Speed-adjusting System of Permanent Magnet Synchronous Motor for Hybrid Electric Vehicle (HEV)
　　This paper reports a series of research and development work on the vector control of Permanent Magnet Synchronous Motor (PMSM) with the aim of its application in the Hybrid electric vehicle (HEV) drive system. The control system combines the electrical motor theories with the modern power electronics techniques, sensor techniques, microprocessor techniques and advanced control theories. As the representative of modern electrical motors, permanent magnet synchronous motor(PMSM) is ideal for advanced Hybrid electric vehicle (HEV) drive systems for its Special shape NdFeB magnets  potentials of high efficiency, high torque to current ratio, and low inertia. Thus, permanent magnet synchronous motor is widely regarded in Hybrid electric vehicle (HEV) control field.The digital signal processor of Freescale Semiconductor, 56F8346,is used as the controller in the study.
　　The mainstructures of the software and hardware parts of the control system are introduced. Principles and realization of the main functional blocks of these two parts are illuminated. On the hardware of the system, parts of control circuit and the design and debugging of peripheral circuits are discussed thoroughly. Based o n the hardware circuit, the software is programmed with C language. Dual close loop vector control with feedback of speed and current are realized. The flow charts of main program and PWM interrupt service routines are given. The important control strategies of vector control PMSM such as current sensing and scaling, speed sensing and scaling, bettor co-ordinate trans- formation, generation of sine and cosine, PI regulators, SVPWM vector modulation and http://www.999magnet.com so on are all accomplished in the PWM interrupt service routines. In order to unite all the variables in the program, scaling is used.We used RS-232 to communicate with the PC and developed the control and display software by the LabWindows/CVI, it controlled the PMSM very easily anddisplayed the data that we needed.Finally, the experimental results validated and deepened the Conclusions drawn from theoretical research. The results fully approved the usability and reliability for the system.

Two Degree-of-Freedom Control for Permanent Magnet Synchronous Motors

　　Two Degree-of-Freedom Control for Permanent Magnet Synchronous Motors
　　The permanent magnet synchronous motors (PMSM) have the advantages of high speed, high efficient, high dependability performances etc., meanwhile has many characters such as low noise, low cost and long life. With the development of the new material, the PMSM has been rapidly developed and widely applied in recent year. The control performance of the servo system is influenced by factors as plant parameter variations, external load disturbances, unmodeled and nonlinear dynamics.
　　At the same time, it needs to notice that the controller Alnico magnets parameter perturbation is also one of the important factors which influence the robustness of the servo system.In order to reduce the influence caused by the controller parameter variations and the plant parameter perturbation, and assurance the tracking performance and the restraint disturbance performance, the improved robust two degree-of-freedom (DOF) control structure and the linear matrix inequation design method are adopted to design the robust two DOF controller of the servo system in this thesis.The improved robust two DOF control structure has the merit of the traditional two DOF control structure. The tracking to the preset signal and the restrain to the disturbance are achieved with two DOF. The asymptotic tracking or the attainment of zero tracking error in the steady-state which is robust with respect to the plant parameters can be accomplished with the robust two DOF. The tolerances of controller parameter variation in two different control structures are compared. The results show that the servo http://www.999magnet.com system with the former control structure has lower sensitivity to the controller parameter variations and has better robustness.In order to simplify the design process of the controller and optimizes the controller performance, the linear matrix inequality method is employed to design the two degrees of freedom controllers in the thesis. It eliminates the influence of the human factors such as theweight function choice, overcome the disadvantage of dealing with Riccati equation and gets the controller by convex optimization.Simulation results show that the servo system with the designed controllers provides a good performance. At the same time, it reduces the sensitivity of the system performance to the controller parameter perturbation. Then, the robustness of the system are improved.

Torque Pulsation of Direct Torque Control Permanent Magnet Synchronous Motor

　　Torque Pulsation of Direct Torque Control Permanent Magnet Synchronous Motor
　　First of all, this thesis introduces the mathematic model of the permanent magnet synchronous motor (PMSM), then simply presents the history and improvement of the direct torque control (DTC). The simulation model for DTC PMSM is set up, and the simulation results show that it has the advantage of fast torque response and the robustness to the variable parameters of the rotor, but the disadvantages of big torque and flux ripples, low inverter’s switching frequency at Neodymium Magnets  low speed hinder its development.In view of big torque and flux ripples of conventional DTC, this thesis presents two control methods based on space vector modulation (SVM). The first is predicting the next PWM period’s flux amplitude and the rotate angle to control the torque and flux. The second uses the sliding mode variable structure controller (SMVSC) to control them. Three simulation systems are set up, which are the open loop SVPWM control system, the DTC system based on predictive thought and PI torque controller and the system based on SMVSC. The simulation results show that both systems using SVM can keep the fast response characteristic of the conventional DTC and http://www.999magnet.com apparently reduce the stator flux and torque ripples. Furthermore, under the same conditions, simulation results show that the system applied SMVSC can produce much smaller torque ripple than the other two DTC systems and is robust to the stator flux estimated angle error caused by stator resistance variation.At last, the control system including the drive and protect circuits of the IPM and the current sample circuits and so on are designed. Using assemble language to realize the conventional DTC system based on TMS320LF2407. The experiment results shows that the torque response is fast but the torque and flux ripples are large at the low speed.

Research on the Performance of Permanent-Magnet Synchronous Motor Servo System Based on DSP

　　Research on the Performance of Permanent-Magnet Synchronous Motor Servo System Based on DSP
　　With the development of modern control theory, power electronics and computer sciences, the permanent magnet synchronous motor (PMSM) ac servo system has been widely applied in many fields because of its high precision and high reliability. However, for the influence of parameter variety and load disturbance, high precision and high reliability servo controller must be designed, to obtain advanced adaptability and anti-disturbance.
　　The operation principle of vector control is given. Neodymium Magnets Disadvantages and advantages of current control strategies are analyzed, also analyzes their apply range. The model of motor and the theory of field oriented control based on vector control are given. The frequency-domain model is established.For servo system based on vector control, the control of torque means the control of current. The engineering design method of current regulator and parameters has been given. The thesis also analyzes factors that influence the performance of current loop. Aimed at the zero drift and back EMF, the method which can reduce the influence has been given. The experimental and simulation results indicate that the over modulation can improve the performance of current loop.Fast and accurate speed response is needed in high performance servo system. The engineering design method of speed regulator and parameters has been given. The influence of load disturbance can be compensated by load torque observer, and the dynamic performance of speed control can be improved by it. http://www.999magnet.com    The low speed problems have been analyzed, and the method to reduce the error of low speed feedback has been given.The position of the rotor must be known accurately in servo system. For position feedback error caused by error installation of incremental encoder, two zero adjustment methods have been given, the position feedback error can be reduced by these two methods. The thesis also gives the method of getting the initial position of rotor.The structure is the base of high performance servo system. The digital servo controller based on DSP has been designed in this thesis, including protecting and monitoring circuits. And the analog current loop and the digital speed loop are introduced. The experimental results indicate the feasibility of proposed optimizing methods.

Optimization Design Research of the Radial Permanent Magnet Low-speed Synchronous Electromotor

　　Optimization Design Research of the Radial Permanent Magnet Low-speed Synchronous Electromotor
　　For the purpose of improving the cost-performance ratio of the radial NdFeB permanent-magnet low-speed synchronous electromotor, the paper analyzes and studies the basic theory and parameters of the low-speed electromotor, and makes the electromagnetism design, which is regarded as the basis of optimization design. Considering that NdFeB permanent-magnet is Neodymium Magnets much expensive, the paper uses a mixing optimization algorithm based on Genetic Algorithm and the multi-skill method. On the premise of guaranteeing the performance index of low-speed electromotor,the paper optimizes the volume of permanent magnet, which can’t only realize the overall optimization, but also achieve the goal of fast constringency. Optimization result indicates that the cost-performance of the electromotor raises obviously after optimized by the mixing http://www.999magnet.com optimization algorithm. In addition, the paper also carries on simulation research by the MATLAB software, and the simulation result shows the advantages of the optimization algorithm too. The paper has important reference value to the theory study and the manufacture of the low-speed electromotor.

The Design and Characteristics Analysis of the Permanent Magnetic Wiggler

　　The Design and Characteristics Analysis of the Permanent Magnetic Wiggler
　　The synchrotron radiation, which is a kind of outstanding X ray source, is an almost the only research tool in the front research of many fields. With the high requirement of its characteristics, the capability and varieties of the magnets which produce the synchrotron radiation are continuously reformed. On the basis of much unique characteristics, the multipole permanent magnetic neodymium magnets wiggler becomes an economic and effective insertion device which can be used for advancing the synchrotron radiation.This paper is based on the projects of construction of for upgraded Beijing Synchrotron Radiation Facility (BSRF),which name is“The Research and Design of the Mutipole Permanent Magnetic Wiggler”. The characteristics of synchrotron radiation output from the multipole wiggler magnet were summarized, and calculating formulas of correlative parameters were presented. Influences of the multipole wiggler magnet on the stability of electron beams were briefly analyzed.According to the designing requirement of the multipole permanent magnetic wiggler which was presented by the synchrotron radiation and accelerator. Physical design and optimizing methods, as well as its http://www.chinamagnets.biz designing principle and traits were discussed. The framework parts used for bearing the main loads were analyzed in order that the integral structure strength meets the required mechanical precisions. The magnetic field measurements including single permanent magnetic bolcks measurement and whole wiggler magnet measurement were finished, and their analyzing results were presented.Through the analyses of synchrotron radiation characteristics ,and the measurement of mechanic structure precisions, as well as the magnetic field measurement, the multipole permanent magnetic wiggler is obtained that both its physical and structural designs gain project’s ends.

Study on Design and Features of Small-to-Medium Permanent Magnetic Generators Directly Driven by Wind Turbine

　　Study on Design and Features of Small-to-Medium Permanent Magnetic Generators Directly Driven by Wind Turbine
　　In a conventional wind power plant, a generator is coupled to the turbine via a gear-box in order to reduce its sizes. However, the gear-box brings some problems such as producing noise, needing regular maintenance and increasing losses etc. In order to overcome these problems, the direct-driven style is being used nowadays. Permanent magnet generator direct driven (DPMG) by wind-turbine becomes the tendency of wind power development. In our country, the study of DPMG is being at initial step and the small-to-medium wind power plant for stand-alone generation-battery Special shape NdFeB magnets system directly driven by wind turbine is quite fit to remote village, pasture, frontier or coast defensive station due to its operating reliability and low cost. It is profound significance to improve the conditions of these areas.In this study, DPMG will be designed with "fat and short" style, i.e. its diameter is large while its length is small.
　　More turns of winding is needed to produce enough voltage because the DPMG rotates at low speed, but the armature reaction is high at same time. The DPMG has a large number of poles in order to get the necessary frequency of the output voltage. Simple and reliable PM rotor structure is a favorite with small-to-medium DPMG design.The preliminary design and machine parameters are determined by means of the traditional design method of PM machine. The waveforms http://www.999magnet.com of voltage, current and electromagnetic torque for different loads can be calculated based on FEM combined with circuit analysis. The effect of different poles and slots on the machine performance is analyzed in detail. Based on the comparison of different design schemes, the final decision can be made, and some design features of small-to-medium DPMG can be deduced. Two prototype DPMGs have been designed and built. The test data verified the correctness of the proposed design method.The DPMG is a kind of synchronous generator with unchangeable excitation. Due to the changeable wind speed, the output frequency and voltage of the DPMG are not constant, and need to be converted into constant through AC-DC-AC converter.

Research on Position Control of Permanent Magnet AC Servo System and Correlative Technologies

　　Research on Position Control of Permanent Magnet AC Servo System and Correlative Technologies
　　Permanent magnet synchronous motor(PMSM) system has become mainstream product in the servo system field because it has more advantages over DC motor servo system. With the progress of micro-electronics and power electronics and the maturation of new control strategies, AC servo system has changed from analog control method to digital.In order to Neodymium Magnets analyze the characteristic of PMSM field-orientation control system exactly and optimize the controller parameters, the linear model is established and transfer functions of each unit are deduced. Then, principle and realization of electronic gear are researched. Complex control is implemented for improving position controller dynamic characteristics, and its validity is acquired by simulation and experiment.
　　By analysis of the factors of current odd, a real-time compensation method is presented based on pulses to minimize linearity of power inverter. In addition, voltage space vector pulse width modulation is discussed and implemented based on DSP in this thesis.Finally, design solution for PMSM system is implemented based on Lattice’s ispLSI1032E and TI’s TMSLF2407A. A novel current sensing IC is adopted to avoid temperature drift of A/D converter, http://www.999magnet.com and current sampling is realized by virtue of high speed DSP. A effective self-start method of PMSM is presented, which uses complex encoder inside motor by adding a section of initial routine. ispLSI1032E is used to achieve a converter for interface signals, which processes instruction pulses and gives the results to DSP. In this system, lots of protecting circuits are designed in order to ensure it runs safely and reliably.Additionally, this system is simulated by Matlab/Simulink, and experiments are also accomplished. The results show its advantages---quick orientation, high reliability and low cost.