Research on AC Permanent Magnet Synchronous Motor Servo System

　　Research on AC Permanent Magnet Synchronous Motor Servo System
　　With the development of material technology,power electronics technology, control theory,computer technology,miero-electronics technology and the improvement of motor manufacture level,alternating current(AC) permanent magnet synchronous motor(PMSM) servo control system is widely used in all kinds of industry areas.For its exeellent performance and various configurations,PMSM is used in many fields,such as agriculture,human’s live,aviation,spaceflight and national defense.We drive and control PMSM with frequeney conversion electrical source to gain more excellent performance and more accurate precision.So the research of timing control system of PMSM is very important.This thesis,based on analyzing the strueture and mathematies model of PMSM,empolders the digital servo
http://www.999magnet.com/products/131-magnetic-lifter
 system of vector control of PMSM through using the TMS320F2812 of TI Company as its core.This thesis from the background and significance of topic,introduces the general development situation of AC servo system of PMSM.Then not only the mathematic model,operation principle of PMSM and the basic theory of vector control for PMSM are all illuminated,but also the theory and algorithm of voltage space vector pulse width modulation is analyzed.
　　On the basis of the principle of vector control,four current control methods of PMSM vector control are discussed in detail.It suggests that the rotor field-orientation vector control of i_d=0 can be chosen,in view of the surface mounted PMSM used in the item.Based on automation theory,the configuration and mathematical model of all parts of PMSM servo system are analyzed carefully.The three loops of the system are designed with the help of engineering design method of automation system regulator.The simulation of the system is taken,and the stability of the system is studied.Then the system hardware and software design are narratived.The Microprocessor and peripheral circuit,the main loop circuit,power module, detectiing circuit and system protection circuit of servo system are introduced in hardware design;in software design,this thesis introduces the design of the control program,main control program and timer1 underflow interrupt program structure. More it introduces some sub-program,like the rotor position and speed adjusting, the current sampling and adjusting,SVPWM program e.g.Finally,some experiments are done on the experimental platform of the whole system.The final result shows that this system can satisfy basic requirements of the servo system performance. 更多还原

Optimization Design and Digital Control Research on Bearingless Permanent Magnet-Type Motor

　　Optimization Design and Digital Control Research on Bearingless Permanent Magnet-Type Motor
　　A Bearingless Motor is a novel electro-magnetic machine that has the functions of the electric motor and an active magnetic bearing.Bearing windings are wound together with conventional torque windings to produce radial suspension forces in stator slot of the bearingless motors.The rotor is successfully supported by electromagnetic forces and rotates as the conventional motors.Compared to traditional permanent magnet motor,permanent magnet type bearingless motor has a serial of more advantages,such as no mechanical touch,no wear, high-speed,high-precision and long http://www.999magnet.com/products/108-alnico-magnets life-span.So it has potential prospect application in those special electric transmission fields of bioengineering,aviation,new energy sources, semiconductor manufacture and medicine sanitation and so on.Thus the research on permanent magnet-type bearingless motor has attached special attentions.The main works of this dissertation are as follows:Firstly,the basic configuration and function principle of permanent magnet-type bearingless motor are discussed in detail and the mathematics model of motor is deduced.Then,the theory of rotor flux orientation control is adopt to realize the independent control of circumrotate and suspend stably to the rotor as well as decoupling control between torque force and radial suspension force.Also,the decoupling control diagram of the permanent magnet-type bearingless motor is given out.Secondly,the model’s design of the permanent magnet-type bearingless motor is studied. And the designs to the structure of permanent magnet-type rotor,torque winding and suspension winding are analyzed in detail.
　　At the same time,the influences to torque performance and suspension performance because of the permanent magnet thickness are lucubrated.Based on this, the number of turns of torque winding and suspension winding,optimal suspension force,optimal output power are optimized by using ANSYS software.Furthermore,the basic work theory of the permanent magnet-type bearingless motor is testified.It educes that radial force which can suspend rotor is produced surely when torque winding and suspension winding electrified at one time.Finally,based on rotor flux orientation control of permanent magnet type bearingless motor and its mathematics model,the structure of digital control system is designed and simpled for permanent magnet type bearingless motor.Then,the hardware and software of digital control system is designed based upon TMS320LF2407 of TI Corporation.The digital control system is debugged and optimized.The experimental results of digital control system are given and the results of debugging validate that the control strategy and control system satisfies the needs of control.

Direct Torque Control of Permanent Magnet Synchronous Motor for Hybird Electric Vehicles

　　Direct Torque Control of Permanent Magnet Synchronous Motor for Hybird Electric Vehicles
　　The dissertation is presented to the study on permanent magnet synchronous motor (PMSM) drive system for the tandem hybrid electric vehicles (HEV) application. Direct Torque Control (DTC) method is quoted from drive characteristic on electric motor control witch through theoretical analysis, computer simulation or experimental validation. The Maximum Torque Per Ampere (MTPA) control has be introduced for optimizing the traditional DTC method which http://www.chinamagnets.biz could ameliorate the control performance. For more speed governing scope, field-weakening control has been carried out above the basic speed. Enhancing the field-weakening capability could upgrade high speed performance for HEV running. The main contributions of dissertation as follows:Firstly, the MTPA control strategy in constant torque area strategy in constant power area is analyzed through structuring the PMSM mathematical mould, which the DTC method on PMSM has been studied further deeply. The influence of different parameters on the PMSM output power, torque and extend speed capacity witch has be analyzed. The field weakening control strategy in constant power area is analyzed through structuring the PMSM mathematical mould. The modified parameters switching method has be applied in the constant torque area and the constant power for simulation. The more effective DTC method witch combines MTPA has be compared with traditional DTC could reduce more ripples of the DTC in the low speed region.
　　The simulation analysis could pave for the further experiment research with foundation.Secondly, the PMSM DTC control system test-bed has be build including both the software and hardware of the Based on TI company DSP designed for motor control on TMS320f2812 micro-chip for a full-digital PMSM control system. The hardware drive design for DSP interface circuit and the power control circuit combine with C computer language program for DTC been studied further deeply in DSP.Finally, the experiment has been done for the research. Results of the experiment and simulation indicate validity of the reducing speed and torque ripples from traditional DTC in low frequency running and the field-weakening method for HEV which introduced in the paper. 更多还原

KwangSoo;YOON JungHee;RYU DaeWon;KOO

作者:LEE JinWuk;LIM KwangSoo;YOON JungHee;RYU DaeWon;KOO

BongHo;KOH EuiKwan;HONG ChangSeop;
关键词:tungsten, manganese, cyanide, crystal structure, single-

chain magnet
单位:Department of Chemistry, Research neodymium magnet Institute for Natural

Sciences, Korea University, Seoul 136-713, Korea;Nano-Bio System

Research Team, Korea Basic Science Institute, Seoul 136-713,

Korea;
摘要:Reaction of unique [W(CN)6(phen)]- http://www.everbeenmagnet.com with a magnetically

anisotropic Mn Schiff base yielded a WⅤ(5d)-MnⅢ(3d) bimetallic

compound with a linear chain structure. The magnetic properties

of the chain complex feature a ferrimagnetic behavior as well as

slow magnetic relaxation typical for a single-chain magnet.

calixarene, lanthanides, single molecule magnet,

关键词:calixarene, lanthanides, single molecule magnet,

photoluminescence
摘要:The syntheses, crystal structures, magnetic and luminescent

properties of three isomorphous compounds [Ln III 6 (μ 4-O) 2

(C4A) 2-(NO 3 ) 2 (HCOO) 2 (CH 3 O) 2 (DMF) Neodymium mIknatIslar 4 (CH 3 OH) 4 ] (Ln =

Gd (1), Tb (2) and Dy (3); H 4 C4A = p-tert-butylcalix[4]arene)

are reported. These three compounds http://turkey.chinamagnets.biz are featured with the

sandwich-like units constructed by two tail-to-tail calixarene

molecules and an in-between Ln III 6 octahedron. The Dy III

compound exhibits both single molecule magnet behavior and

photoluminescence.

作者:刘武;陈文元;张卫平;黄晓刚;张忠榕;
关键词:diamagnetic levitation; permanent magnet; micro-electro-mechanical systems (MEMS)
单位:Research Inst.of Micro-Nano Science and Technology Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China
摘要:A novel micro-machined diamagnetic stable levitation system (MDSLS) which is composed of a free permanent magnetic rotor, a ring lifting permanent magnet and two diamagnetic stabilizers was presented. The static and dynamic stable characters of MDSLS were analyzed. The coupled non-linear differential equations were used to describe six-degree-of-freedom motion of the levitated rotor, and the equivalent surface current and combined diamagnetic image current method were utilized to model the interaction forces and torques between the lifting permanent magnet and rotor permanent magnet and also between the rotor permanent magnet and diamagnetic substrates. Because of difficulty to get analytical solution, the numerical calculation based on Runge-Kutta method was used to solve the dynamic model. The vibration frequencies were identified by fast Fourier transform (FFT) analysis. According to their resonance characteristics and parameters, the translational and angular dynamic stiffness were also calculated. The results show that the levitation of the rotor in MDSLS is stable, and the MDSLS is potential for the application in levitation inertial sensor.

Fe-Cr-Co-V-Ti permanent magnets

作者:齐凤春
单位:Department of Physics, Dalian Institute of Technology
摘要:<正> Fe-Cr-Co-V-Ti permanent magnets magnetic materials
http://www.999magnet.com are characteristically

free of harmful phase as V contributes to enlarging the α phase

region. At an earlier date, the V content was fixed at 3～5％(wt

％)(Kaneko, H. et al., 1976 and 1978), its B_r and (BH)_(max)

values approach the level of semi-columnar crystal AlNiCO5

magnets, but its H_c value was less than 48.0 kA/m (600 Oe).

However, we later found that the efficient content of V might be

reduced