Simulation Comparison of DTC and SVPWM for PMSM

　　Simulation Comparison of DTC and SVPWM for PMSM
　　Permanent Magnet Synchronous Motor (PMSM) has characteristics of small volume, light, efficient, small inertia and reliability. It is widely used in servo , underwater propulsion. There were lots of papers about Direct Torque Control(DTC) and Space Vector Pulse Width Modulation (SVPWM) method to control the PMSM in the past, but there were few papers about the differences and advantages and disadvantages of the two technologies.Firstly, the paper Block neodymium magnet discusses general outline of speed control methods and control strategies of PMSM. The paper introduces the main developing directions of PMSM. The purpose and the main content of the project are given in this dissertation, too. Then according to the mathematical models of PMSM, paper analyses DTC and SVPWM control strategies ,which are advanced methods. The DTC gets rid of circumrotating coordinate conversion and decreases dependence of system on motor parameter. According to current and voltage of stator, to calculate amplitude of torque and flux linkage. So to reach the aims of direct control torque and flux linkage. By detecting the current , voltage and rotor’s angle. then through space coordinate conversion , we get expectation of stator flux linkage vector. Then we modulate the expectation of stator flux linkage vector to control torque and rotation speed of motor. http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php Using MATLAB/SIMULINK mathematic tool ,we construct the two models.Digital simulation technique always is useful tool in analysis and calculation of ac adjustable speed drive system. We use MATLAB/SIMULINK mathematic tool to simulate the two control strategies and obtain the torque, current, flux linkage ,etc curve. By comparing two systems, We can get the result——DTC system has excellent torque dynamic control characteristic but it also results in large ripples of torque , current and flux linkage. SVPWM system’s ripples of torque , current and flux linkage are smaller than DTC’s, but the control system is more complex.

The Research and Development of the Speed Regulating System of Automotive Air-condition Fan

　　The Research and Development of the Speed Regulating System of Automotive Air-condition Fan
　　With the development of the technology and the improvement of the people’s life level, people have more requirement to the comfort of automobile. Therefore, many kinds of automotive air-conditions system come out rapidly. The speed regulating system of the air-condition fan influences the air-condition system’s performance of adjusting the temperature in a large extent. The engineer all over the world are studying the better speed regulating system of air-condition fan.According to the change of the environment’s temperature and people’s different requirements to the automotive inner temperature, comfort and saving power, it is necessary for air-condition fan regulating the speed in all kinds of situations in order that it can adjust the exchange ratio of the inner rubber magnetic sheet air temperature and wind speed of the exit of air-condition fan, thereupon, the different requirements of passengers are satisfied, consequently, it is necessary for air-condition fan to regulate speed, and then it appears many varieties of the speed regulating system of air-condition fan.DC motor has the high running efficiency and benign performance of speed regulating, therefore, the early speed regulating systems of automotive air-condition fan mostly adopt DC motor to regulate the speed. DC motor adopt the brush to change direction, so the reliability and life-span of the system is being reduced, in the mean time, it can lead strong electromagnetic interference, as a result of that, the other electrical system of the automobile and environment can also be influenced.With the maturity of the technology of the AC frequency conversion, asynchronous motor speed regulating system has a extensive application in each industrial field.
　　This kind of speed regulating system has the merits such as simple framework, credibility of working, without mechanical abrasion and less electromagnetic interference, thereby, it gradually replace the DC motor speed regulating system. On the other hand, the power factor of the asynchronous motor is low, so it faces the trend that it will be replaced by the brushless DC motor speed regulating system whose performance is much better than former system.At present, research personnel put more energy on the study on the permanent brushless DC motor speed regulating system of air-condition fan, in order that the speed regulating system of automotive air-condition whose performance is better than before face to the world as early as possible. Permanent brushless DC motor can be divided into two kinds. The one has position sensor, the other has not position sensor, it is called sensorless one. The research on the latter one is hotspot.The detecting system of position sensorless does not need mechanical position sensor. At the present time, the research core and key on position sensorless brushless DC motor controlling is detecting circuitry of the framework rotor position signal. The rotor position signal can be gained from software and hardware credibly, and then touch off the corresponding power apparatus, later, the motor run.Recent years, there appears a lot of the method of detecting rotor position worldwide. There are several kinds in general below: the method of inverted-electromotive force,the method of using inductance, the method of state observer,the method of vortex, the method of Kalman filter, the method of estimating magnetic chain.
　　The aim of this dissertation is the study on the speed regulating system of automotive air-condition fan, the content and conclusion is below:1.Introduce the developing status quo of speed regulating system of automotive air-condition fan, analyze the merits http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php and defects of three kings of speed regulating system of automotive air-condition fan, indicate the research significance and content of dissertation.2.Analyze the base framework and working theory of brushless DC motor, demonstrate the rotor position detecting and switch circuitry case of brushless DC motor. This article adopt a newly detecting method to achieve the rotor position detecting, it is called the method of G (θ) function. The result proves that this method is a effective one.3.Analyze the working theory and feature of the PID control system, introduce the theory and composing of the fuzzy control and double fuzzy control specially and feasibility and advantage of using former theory in the speed regulating system of air-condition fan. Finally, choose the method of fuzzy PID control to apply to the speed regulating system of air-condition fan control.4.Setup the mathematic model and simulating model of speed regulating, analyze by simulating, evaluate the control strategy. Through comparing with the double PI adjusting simulation, the advantage of the fuzzy PI control strategy is obvious. Fuzzy PI control strategy has benign steady precision , less steady error and strong ability of countering the http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php interference. Thereby, with the development of modern control technology, fuzzy PI control will apply in variety of speed regulating in a large extent.5.Finish the software design of speed regulating system of automotive air-condition fan. As the limit of condition, this article does not finish the hardware design of the system, this is the main direction of next step work.Position sensorless permanent brushless DC motor speed regulating system of automotive air-condition fan will realize in the late future, produce in many batches and apply in the real car. The study on this system will promote the development of the motor controlling, and naissance more applied method of detecting.

微型电动汽车驱动控制系统研究

　　微型电动汽车驱动控制系统研究
　　To reduce energy consumption and decrease the hazardous tail pipe emission, significant efforts have been accumulated globally to push the Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) program into mass-production stages. Consequently, it is expected that the internal combustion engine powered vehicles will eventually be replaced Block Ceramic Magnets by electric ones.The thesis is focused on the study of the permanent magnet brushless DC motor (BLDCM) drive with application to Electrical Vehicles. The main work is the design of a high performance control system based on a TMS320LF2407 DSP.Firstly, based on the comprehensive review of the characteristics and control methods of BLDCM, the operating states and control strategies of a BLDCM with applications in EV are proposed with respect to Power electronics, Electronic technology, Micro Electric technology, special integrated chips and the theory of Motor control theory.The velocity closed-loop control system for a BLDCM based on DSP TMS320F2407 is then designed. Thirdly, the performances of the control system are numerically studied by using Simulink. Finally, the designed control http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php system is experimentally investigated on a prototype motor. Both numerical and experiment results show good agreements with each other, which positively confirms the feasibility and practicability of the proposed control system.

注射成型粘结稀土永磁体的研制

　　注射成型粘结稀土永磁体的研制
　　This article discusses in the foundation of the injection rare earth permanentmagnet compounded lnaterials, and pointing out main problems which exists in thedevelopment and the production areas. The rare earth magnetic powder’s surface,composition for rare earth bond magnet, and property of the injection rare earth permanentmagnet compounded materials were studied. Furthermore, the relationship between theflow of the injection and the property of the materials was discussed.The surface properties of rare earth magnetic powder and polymer resin areentirely different, so their compatibility is very bad. In order to get two unions togetherwell, their compatibility must be changed firstly. The surface impact between the rareearth magnetic powders and the polymer resin was weak, and the dispersity of themagnetic powders in resin was bad when the content of the Block neodymium magnet rare earth magnetic powderswere in high fills. How to improve the rare earth magnetic powder’s dispersivity inpolymer, and how to enhance the surface contact, were studied in the paper. The use ofdifferent types of the coupling could improve the rare earth magnetic powder’s surface,and enhance the compatibility between the magnetic powder and the polymer. Theresults of experiment indicated that under the suitable dosage and the flow condition,use of the KH-550 coupling could modify the magnetic powder’s surface, enhancecompatibility between the rare earth magnetic powder and the polymer substrate, andimprove the dispersity of magnetic powder in polymer, so the compound materialdisplayed high longitudinal strength and high elongation ratio. Simultaneously, theresults of experiment showed that the KH-550 coupling could also improve the anti-oxidized ability of the magnetic powder under high temperature.In order to obtain high magnetism performance product, the content of magneticpowder in compound materials was very high; meanwhile, the mixture of grains waschanged to be difficult, and the dispersity of the magnetic powder was changed to bebad. If the fluidity of the injection was bad, the appearance of the product would berough, brittle, and very difficult to satisfy the actual application.
　　In order to improve thefluidity of the melting-body in full filling condition, different types of lubricant function were used in the paper. Though the metallic soap might enhance the fluidity of themelting-body, the dosage was huge, which might cause drops on the mechanics intensityof the product, and cause magnet to be crisp and easy to crack. EBS might enhance http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php thefluidity on melting-body and keep mechanic intensity of the compound materials to behigh. EBO could not only enhance the fluidity of melting-body, but also enhance themechanic intensity of the compound materials。In order to acquire different properties of the rare earth magnet, the relationshipbetween the content of magnetic powders and properties of the compound materials wasstudied. The magnetic property of the compound materials would be high if thecontent of the powders is high. While, high content of the magnet powders may causethe fluidity to become bad and hard to forming and process, and the mechanic intensityto drop sharply. When the neodymium iron boron (NdFeB) magnetic powder content is94 wt %, or the samarium cobalt (SmCo) magnetic powder content is 95 wt %, idealinjection bond magnets might be obtained.In conclusion, the influence of the flow condition to the magnetism performance,and emphases of the injection flow condition to the aeolotropism samarium cobaltmagnet were studied in the paper. In order to obtain the injection samarium cobaltmagnets with high performance, high injection temperature, mould temperate andquickly injection speed must be needed.

Research and Implementation of Doubly Salient Electro-magnet Starter-Generator System

　　Research and Implementation of Doubly Salient Electro-magnet Starter-Generator System
　　Doubly Salient Electro-magnet Machine is a new type Machine that derived from Doubly Salient Permanent-magnet Machine, it inherited the advantages of simple structure, high reliability and being fit to high speed operation from DSPM.In the mean time, the problems of voltage regulating and eliminating magnetism under fault state were solved owing to the advent of DSEM. At the present time, the engineering of 270V high voltage DC generator Ball Neodymium Magnets system using DSEM has appeared. In addition, DSEM has the characteristic of high torque-current ratio and good performance when it’s used as motor. So DSEM has become one of candidates applying to future starter-generator technology for aeronautics, study on forming starter-generator system based on DSEM is very necessary.This paper introduces the structure and magnetic characteristics of DSEM starter-generator firstly, and describes mathematic model and operation principle of DSEM starter-generator in succession, finally,the characteristics of DSEM starter-generator are summarized. These contents are foundation of following research.Experiment validation is important step of subject research, this paper establishes experiment platform of DSEM starter-generator system,this system constitutes of power converters and corresponding hardware and software based on DSP & CPLD.The work process of DSEM starter-generator system consists of starting process, starting-to-generating state conversion process and generating process, this paper establishes the simulation models using http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php MATLAB based on different work processes, and fulfills theoretical analysis and digital simulation of control methods under different work processes.
　　DSEM starter-generator system do exists different fault states during different work processes, include power converter faults and electric machine faults, theoretical analysis and digital simulation of fault states and partial experiment validation based on starting process is done in this paper. And results prove that DSEM starter-generator system has good fault-tolerance under certain fault states.This paper finally introduces the configuration of DSEM starter-generator experiment system and partial experiment results under different work processes, the experiment results prove the validity of design and feasibility of DSEM starter-generator system.

空压机用永磁电机控制系统的研发

　　空压机用永磁电机控制系统的研发
　　Reciprocating compressor plays an important role in the national economy for it’s advantages like wide-range use and so on. In our country, reciprocating compressor is mainly droved by asynchronous induction machine, which leads the fact that the efficiency is very low. At present ordinary Permanent Magnet Control system usually accept PI control arithmetic with the velocity and torque feedback equipment as its controller. However rubber magnetic sheet the price of this controller is still high comparing with the low-cost compressor, meanwhile air force in the compressor is varying according to the motor’s rotation, which means the load of the motor has periodical ripple. In this situation, the character that stability is in contradiction with response velocity of PI parameter integration method is obvious.
　　In some critical situation where sophisticated control is needed, the Permanent Magnet Synchronous Motor is usually used as the air compressor driver. However, the control is quite complicated and expensive. In order to solve this contradiction, a low-cost control especially for reciprocating compressor was proposed.In the dissertation, reciprocating compressor’s torque characteristics on the condition of single compression, double compression in the same pressure rate and double compression in different pressure rate were analyzed in detail from the viewpoint of compressor design. Research on optimizing the resistance characteristic of the compressor was done to facilitate the control development.Theories for Brushless DC Motor and the direct torque control of the Permanent Magnet Motor were presented. On the basis of the idea of direct torque control as reference, and took the reciprocating compressor’s torque into consideration, varying duty-cycle control method was put forward. Simulink toolbox and simulation programs written in MATLAB were used to http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php verify the feasibility of this method.Torque ripple due to untimely phase conversion was analyzed in detail. Mathematical models for back-EMF current and torque ripple in untimely phase conversion were developed. An experimental circuit board was built for the proposed control system, including the rectification circuit, power driver circuit, back EMF detection circuit and so on. PIC programs were written to implement functions like phase conversion jump-start, back EMF detection and so on.A proper curve obtained through experiment, which represents the relation between voltage and frequency, was presented to guarantee that the motor could jump-start steadily. Experiment verified that capacitance, duty-cycle and frequency would affect the detection of back EMF; and that the varying duty-cycle control method is necessary and feasible, which provides a novel design way for the Brushless DC Motor used as compressor driver.

The Development of PMSM Servo Drive Controller

　　The Development of PMSM Servo Drive Controller
　　This project is consigned by GSK CNC Equipment Co., Ltd, in cooperation to develop the high-speed and high-precision machine tool servo drive controller. According to Computer Numerical Control (CNC) Machine Tool Feeding Control, using the sensored Field Oriented Control (FOC) and Feed-forward Compensation Control Theory, designs the Permanence Magnet Synchronous Motor (PMSM) servo drive controller base on the TMS320F2812 DSP controller.The mathematical model of the PMSM and the vector decoupling control neodymium standard state strategy are analyzed. Coordinates transform equation are given. Compare several realizations of vector control method, and id=0 method is chosen. Trandsducer control of servo motor driver based on SVPWM is realized.This system includes TI’s DSP-TMS320F2812 and TS5668M21 17-bit absolute encoder, that make a great improvement in Real-time processing capability and the Positioning accuracy. Design software system using modularization thinking. Following the principle of "functional independence" optimization program structure, System software modules are into Main program and vector control. Using the anti-windup PID controller and the with speed and acceleration feed forward position controller,increasing the steady and Positioning accuracy.This paper analyzed the Parameter setting of current loop, speed loop and position loop ,The proportion degree method is used in rectification the PI parameter. Its http://www.999magnet.com/products/112-neodymium-standard-state validity is verified in simulating experiment and it is reference for real system turning. In this paper the relationship of current with loss of permanent magnet synchronous motor is achieved by considering the copper loss and iron loss. and the control algorithm of current vector minimizing the electrical loss is proposed .Simulation result have shown that the proposed loss minimization control significantly minimizes the motor electrical losses and greatly improves the efficiency compared with the conventional control method.

Research on the DSP Based Sensorless PMSM Vector Control System

　　Research on the DSP Based Sensorless PMSM Vector Control System
　　The dissertation researches on the PMSM vector control system using Extended Kalman Filtering (EKF) algorithm. The main contents are as follows:Firstly, briefly introducing Coordinate transformation thought, PMSM Model in the static coordinate system and the revolving coordinate system and Vector Control principle. Based on the model, the sensorless PMSM vector control speed adjustment is discussed.Secondly, the thesis emphasizes the illustration of the principle of the EKF and it’s application in the system, deduced the EKF Alnico Magnets equations of PMSM in the static coordinate system and the revolving coordinate system. The control diagram is provided, and some optimized methods are proposed. The simulation model of the Vector Control system of PMSM based on the EKF is established and the application of the sensorless in motor control is successfully realized. The reasonability and validity of the EKF programmer in the motor control have been testified by the simulation results.Lastly, this paper uses the Motorola 56F8346 Digital Signal Processor (DSP) as the core of the motor control. The main structures of the software and handware are introduced. The http://www.999magnet.com/products/108-alnico-magnets main functional blocks are illustrated. To the hardware, each part of the control circuit and the design of the peripheral circuits are thoroughly discussed. The control software is being programmed with C. The flow charts of main program and PWM interrupt service routine are given.The program is being debugged in the IDE of Metrowerks Codewarrior so as to test the correctness of the system design.

Study on Low-Speed and High-Torque Gearless Drive System

　　Study on Low-Speed and High-Torque Gearless Drive System
　　Nowadays, permanent magnetic synchronous motors (PMSM) are used very widely in many industry fields, especially in elevators and high precision servo systems, because of their advanced performances beyond other motors. What’s more, Block neodymium magnet permanent magnet material-rare earth is very rich in our nation;therefore, doing research on the control system for PMSM has great science significance and application value.This paper introduces a novel gearless drive system of low-speed and high-torque (LSHT) PMSM for elevator. It that supplied with spatial vector pulse width modifying (SVPWM) inverter can directly drive elevator without decelerator. This direct drive of elevator has not only simplified the construction of transmission mechanism which improved transmit power density and efficiency of the drive system, but also increased precision and reliability of the control system. In this system, rotor position observation is innovative point which avoids a lot of questions caused by mechanic sensor.
　　On the theory, according to the mathematic model of PMSM, the paper presents and realizes i_d = 0 control strategy after analyzing the advantage and disadvantage of diversifiedcontrol strategies. Based on low-speed motor drive system, the design adopts a novel approach of rotor speed/position estimation based on adaptive control. Furthermore, it introduces http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php SVPWM technology in order to reduce harmony of the system. This paper uses the simulation software MATLAB/Simulink to simulate the drive system of low speed and high torque PMSM and the results show that the system models are rightly built and control strategy is feasible. On the basis of hardware TMS320LF2407 of PMSM control system, the paper composes the complete control software using assembly language and realizes stator phrase current sampling, phrase voltage calculation, rotor speed/position observation and output of drive signal. Finally, the inverter-motor model drive system of 1 lkW PMSM is successfully designed and the data of experiment verifies that the proposed vector control scheme is valid, and the dynamic and static performances are quite well. Furthermore, the propose strategy has stronger robustness.

The Research on Control System of Sensorless PMSM

　　The Research on Control System of Sensorless PMSM
　　Permanent magnet synchronous motor (PMSM) have no exciting current in the rotor, and are of high efficiency and power density. But motion control of permanent magnet synchronous motors requires accurate position and velocity signals to accomplish field orientation. In conventional motion control systems, optical encoders or rotary transformer Ball Neodymium Magnets are used for these purposes. However, these additional sensors increase the costs of the system and reduce the reliability. With this background, the research based on the abolishment of these sensors to increase the reliability and decrease the costs is becoming popular.International Rectifier Co. offers a new controller family referenced IRMCF341, which is specifically designed for the needs of sensorless digital motor control. In a single chip application, this device combines a fixed point core with micro-controller peripherals, which combines high-speed signal processing and the ability to optimize motor control peripheral integrated circuits, drive control can provide a reliable and efficient high-performance signal processing and control.On the basis of the summary for the development and application of PMSM motor http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php speed-variable system, this dissertation introduces a control system, which uses IRMCF341 to control the commutation and speed of PMSM. The basic structure, operational principle and design method of this system are set forth in this dissertation. The thought of hardware design and software programming is introduced as well. At last, the experimental results presented are reasonable, feasible,so that the effect of motor control is well.

Electromagnetic Field Analysis of a DSPM Based on Finite Element Method

　　Electromagnetic Field Analysis of a DSPM Based on Finite Element Method
　　The Doubly Salient Permanent Magnet Motor (DSPM) is a new kind of AC variable-speed drives motor,it was introduced in 1990s with the developing of power-electronics and micro-electronics.Recently, more ana mor attention and research having been paid to this motor because of its advantages,such as simple structure,flexible control,quick response,high reliability, high efficiency, etc. At present, in our country and oversea , the research on DSPM is mainly focuses on two directions: one is the basic theory of the DSPM, another is control system neodymium standard state development.On the base of reviewing the development history of DSPM motor, introducing its research situation in our country and overseas,understanding its components, A novel 12/8-pole stator located PM motor is designed according to DSPM theory, in this paper, The main contents are as follows:At first,the paper briefly introduces the fundamental structure, operation principle and mathematical model of the DSPM motor; secondly,the static-state characteristics of the model DSPM are analyzed based on two-dimensional (2D) whole field finite element analysis (FEA) in ANSYS, including flux linkage characteristic, inductance characteristic and torque characteristic,as a result the magnetic field distribution at http://www.999magnet.com/products/112-neodymium-standard-state different rotor positions is found; at last, the influence of air-gap on the DSPM’s static characteristics is analyzed in this paper, The calculation results show the airgap is great influence to the DSPM torque size and the torque ripple,And this offer an important theoretic underground for the research deeply and design of DSPM .

High-Order Sliding Mode Control of PM Synchronous Motor

　　High-Order Sliding Mode Control of PM Synchronous Motor
　　Permanent Magnet Synchronous Motor (PMSM) has been widely used in aerospace, numerical control machine, robots and so on, due to its desirable features of compact structure, high torque/inertia ratio and low power losses. However, PMSM is a multivariable, strong coupling and nonlinear system, suffering from plant parameters variations and load disturbances. In order to improve the performance of PMSM servo system, the research of control strategy is challenging.Sliding Mode Control (SMC), which is strongly robust to system parameters variations and external disturbances, has a desirable perspective in PMSM control field. To eliminate Neodymium Magnets chattering phenomena in SMC, this paper firstly studies a kind of High Order Slding Mode (HOSM) control method for nonlinear systems. By designing the nonsingular terminal sliding mode functions, robust differentiation estimator and corresponding control algorithm, the chattering-free HOSM control of system is realized. Then, integrating with vector control technique, double loop HOSM control of PMSM speed/position servo system is achieved. Meanwhile, sensorless vector control technique for PMSM is studied and an improved estimation method of rotor position/speed based on sliding mode observer is proposed. Finally, a load torque estimation method is proposed for speed controller and the problem http://www.999magnet.com/products/110-sintered-neodymium-magnets of robust control for systems with unknown load disturbances is sovled. For the current cotroller, an adaptive compensation strategy is designed to compensate the nonlinear disturbances of PWM inverter.The simulation results indicate that, the proposed control method in this paper is correct. The designed HOSM controller for PMSM system can eliminate chattering and guarantee the robustness. The improved sliding mode observer can enhance the estimation precision for rotor position/speed. The adaptive HOSM controller against nonlinear disturbances can improve the performance of motor control.

Structural and Magnetic Study of Melt-spun CeCo5 Ribbons

　　Structural and Magnetic Study of Melt-spun CeCo5 Ribbons
　　RCo5 (R = Y, Ce, Pr, Sm)-type intermetallic compounds with CaCu5 structure have attracted considerable attention due to their large anisotropy fields HA, relatively high saturation magnetizations MS and high Curie temperatures TC. But only SmCo5 magnet has been widely used because there are some technical difficulties in fabrication of several other materials, and no easy access to high-coercivity requested by the fine micro-structure. Rapid quenching (melt-spun) possess controllable rapid cooling speed, which is easy to fabricate small and fine micro-structure. Rapied quenching (melt-spun) has been widely used in Bonded NdFeB Magnets fabrication also for its convenience and low energy consumption. Many researchers have fabricated melt-spun neodymium prices YCo5, PrCo5 and SmCo5 magnet, but the magnetic properties still could not satisfy the practical requirements. Recently, obvious grain orientation of melt-spun RCo5 has been reported, which makes use of melt-spun RCo5 anisotropic bonded magnets possible. CeCo5 posses similar inherent magnetic properties as SmCo5, especially that Ce is much cheaper than Sm in price due to its rich reseves, these make the study on anisotropic melt-spun CeCo5 permanent magnet so significant.In this work, melt-spun CeCo5 ribbons have been made, and the effect of ingredient and cooling speed on gain orientation and magnetic properties have been investigated. In addition, magnetic properties of ribbons have been improved by Cu and Fe doping and annealing treatment. At the same time, the magnetization reversal mechanism has also been discussed and analyzed. The main activities include as following:I. Structure and magnetic properties of CeCo5 binary alloy ribbons 1. melt-spun CeCo5.4 ribbonsR-rich phase has been found in arc-melt Ce-Co alloy with the ratio of 1:5 beside CeCo5 phase, which could be inhibited by increasing Co content, Ce-Co alloy with single CeCo5 phase has been obtained at the ratio of 1:5.4 finally.With surface velocities http://www.999magnet.com/products/142-neodymium-prices (Vr) of the Cu roll are 5 m/s, 15m/s, 25m/s and 35m/s, ribbons have been fabricated. XRD study on no-contact surface of CeCo5.4 ribbons shows that: The existence of the (111) strong peaks in 5m/s ribbons indicates that the crystal grains near no-contact surface have strong axis orientation, most crystal grains’(111) plane parallel to the surface
　　of the ribbons, that is, [111] axis perpendicular to the surface of the ribbons, with the C-axis distributed in the [111] axis angle of about 50o of a cone. The (111) peaks of 15m/s, 25m/s and 35m/s ribbons gradually weakened, the (110) and (200) peaks gradually increased, thus, most C-axis changed to parallel to the surface of the ribbons.Magnetic properties of CeCo5.4 ribbons were tested along the ribbon length, ribbon width and perpendicular to the ribbon plane by Vibrating Sample Magnetometer (VSM), ribbon length direction is always easy magnetization direction. Thinking over the test results of XRD, we can figure out that C-axis should prefer to arrange along the ribbon length direction. For the ribbons spun at Vr=5m/s, the difficult magnetization direction is along ribbon width, and for those spun at Vr=15m/s, 25m/s and 35m/s the difficult magnetization direction perpendicular to the ribbon plane, consistent with the crystallographic texture evident in the XRD pattern’s comparison. Using magnetic moments in three directions and Vr curve to describe the changing trends of magnetic anisotropy as Vr change, we can find out that magnetic anisotropy weakens as Vr increases.Large numbers of angle stripes were observed by scanning electron microscopy (SEM) in the sections of ribbons, which exist in most ribbons. Ares contain stripes shrink as Vr increase, and magnetic anisotropy weaken, so we can relate the stripes with magnetic anisotropy. In addition, scanning electron micrographs for the non-contact surfaces of ribbons show that grain size decrease as Vr increase. On the other hand, coercivity increase as grain size decrease, therefore, it is an effective way to increase coercivity by decreasing grain size.2. melt-spun CeCo5 and CeCo4.6ribbonsAlthough orientated textures exist in melt-spun CeCo5.4 ribbons, the coercivities are too low to satisfy the practical requirements. For the reason that the magnetic anisotropy field of Rare Earth - Transition alloy increases as the rare-earth content increases, we fabricated melt-spun CeCo5 and CeCo4.6 ribbons as well. Besides crystal axis orientation and magnetic anisotropy we find out that, with Ce content increase, the magnetic anisotropy of ribbons spun at low Vr enhanced, and the trend of isotropy with Vr increased enhenced. The coercivities increased as well.II. Structure and magnetic properties of CeCo4.5Cu0.9 ternary alloy ribbons For sintered CeCo5 permanent magnet, precipitation hardening effect could be caused by dropping
　　Cu element, which will improve coercivity. Thus, CeCo4.5Cu0.9 ribbons were fabricated. XRD and VSM test showed that for the ribbons spun at Vr=5m/s and 15m/s strong rystal-axis orientation existed; for the ribbons spun at Vr=25m/s and 35m/s tended to isotropic. Precipitation hardening effect performed good in the ribbons spun at 5m/s for coercivity improved notablely, and hardly performed in the ribbons spun at 25m/s and 35m/s for most Cu solute in Ce(Co,Cu)5, which reduce the anisotropy field and decrease the coercivity.Heat treatments were prepared to further enhance the coercivity. Large numbers of Cu separated out after 15min 400℃anneal, which was test by SEM and EDX. At the same time, hysteresis loop appeared serious Fengyao phenomenon. We conjecture that 400℃anneal process led to Ce (Co, Cu) 5→Ce2 (Co, Cu)17 + Ce5 (Co, Cu)19 + Cu decomposition reaction, the emergence of low coercivity 2:17 phase caused Fengyao phenomenon. After 15min 500℃anneal, less Cu seperated out and Fengyao phenomenon gradually disappeared. Anneal promoted the formation of CeCu5, precipitation-hardening effect caused further improvement of coercivity.III. http://www.999magnet.com/products/142-neodymium-prices Structure and magnetic properties of CeCo4Fe0.5Cu0.9 quaternary alloy ribbonsDropping Cu element can increase the coercivity but decrease the magnetic moment. Therefore, Fe element was dropped to increase magnetic moment without decrease coercivity. Crystal axis orientation existed in CeCo4Cu0.9Fe0.5 ribbons, (111) strong peaks existed in the ribbons spun at low Vr, and crystal-axis orientation existed. Ribbons spun at high Vr trended to isotropy. Dropping Fe element increased magnetic moment and decrease coercivity slightly. Structure and magnetic properties of CeCo4Cu0.9Fe0.5 ribbons could also be imporved by heat treatment. Excellent magnetic properties have been obtained by 500℃anneal for 15 min. On the one hand, coercivity improved significantly, especially for the ribbons spun at Vr=5m/s, the coercivity has reached 4200 Oe, which is far more than CeCo5.4 ribbons’300 Oe. On the other hand, magnetic moment decreased slightly. Furthermore, the coercivity decreased notablely and magnetic moment increased after 600℃anneal for 15 min.

Research and Design on PMSM AC Servo Control System

　　Research and Design on PMSM AC Servo Control System
　　Servo System is a sort of advanced control systems, whose output can respond the external input rapidly and accurately.Due to the great development of the microprocessor technique, modern power electronic technique, control technique and the manufacture technics for the permanent magnet material of motors.higher control performance of Cast Alnico Magnet servo products with lower cost is being a subject of great interest worldwide. Digital controlled AC servo systems, based on Permanent Magnet Synchronous Motors (PMSM) as power converters with advanced control strategies, implemented in Digital Signal Processor (DSP), will be a trend.In this thesis, a set of practical PMSM speed-adjustment system based on DSP controller is developed, especially for the inverter’s, The improved SVPWM pattern was realized in order to decrease the motors torque ripple and http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php enhance the system’s high speed and accuracy. basing on which a relevant method of control strategy is also advanced. analyzing the principle in detail, a software system for putting the method in practice is further developed.At last, the designed controller is simulated under MATLAB/SIMULINK, and the results are gived.

水下航行器推进用永磁电机工作状态热分析

　　水下航行器推进用永磁电机工作状态热分析
　　The advantage of permanent magnet motor is simple structure, mini volume and higher efficiency, so it is used as a propel motor in electric under-water vehicle. In this paper, a study on steady temperature field of a DC permanent magnet motor used in under-water vehicle is presented, and, the effect of the motor efficiency caused by the increase of rubber magnetic sheet temperature is analyzed.First, the heat resource and the limit of the increase of temperature are presented based on normal theory of motor’s temperature increase. Then, the boundary condition of motor’s heat transfer is analyzed, on the theory about heat transfer. And, the motor’s temperature field is calculated by a finite element software, ANSYS, the temperature of motor’s parts is confirmed. In the last place, the decrease of motor’s efficiency is ascertained, and the author brings some advice. http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php All of this presents a theory foundation on motor design and improve.In addition, based on the finite element analyze of motor composed nearly by fifty parts, a method of finite element analyze in multi-part system is founded, which indicates the function of finite element technology in the study on field.

风机用外转子永磁无刷直流电机及其驱动系统的设计

　　风机用外转子永磁无刷直流电机及其驱动系统的设计
　　In china, air-pumps consume more electricity than any other industrial equipments and the consumption of the pumps occupy 40% of the entire electric power. The efficiency of our air-pumps is 10% to 30% lower than abroad, so adapting the pumps for energy conservation is an urgent task. It’s very meaningful for releasing the contradiction between supply and demand of electricity, improving the construction of modernization and narrowing the Block Ceramic Magnets gap between our state and developed countries.The small-scale air-pump (l~10kw) have their own properties.
　　Each individual consumes little but the quantities of the pumps are large. So it is useful to reduce the consumption of the small-scale air-pumps. However few of us think much of it in past time.This paper presents a type of permanent magnetic brushless DC motor for driving small-scale air-pumps. Permanent Magnet Brushless DC Motor (PMBDCM) is a kind of new type motor with the development of power electronics and permanent-magnet material, It is widely used as a high-performance driving machine because of its advantages such as simple structure, reliable operation and convenient maintenance which the AC motors have and the inherent advantages as a DC motor of high efficiency, low magnet excitation loss and excellent speed controllability.We moderate the http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php winds of the pumps by regulate the motor’s speed and by this way we could meet the target of energy conservation. In this paper, we analysis the motor from material, magnet structure, magnetization, and the coefficient of magnet arcs and we provide the structure, principles and design demands of the motor. A prototype of the permanent magnetic brushless DC motor was made to drive the external rotor pumps, and the driving systems was designed by the demand of speed regulating, system protection and cost saving. This control system of brushless direct current motor is based on special integrated circuit. The design scheme is tested and the sample has been manufactured. The simple and predominant performance is shown by the prototype trials. The control system is used mainly in small power brushless direct current motor control.We use the prototype of the permanent magnetic brushless DC motor to drive the small-scale air-pumps and the measured data show that the motor is more efficient, has lower cost and the advantages for industrialization.

Application of Fuzzy Sliding Control Technology in AC PMSM

　　Application of Fuzzy Sliding Control Technology in AC PMSM
　　The PMSM AC servo system control method based on DSP is studied in this paper. First, the characteristics and modern control ways are introduced. Based on the reference in domestic and foreign, the sliding mode variable structure control and fuzzy control are analyzed. Combing their advantages, the fuzzy sliding variable structure control in application of PMSM is introduced. The limitation in sliding mode variable control is the harm brought by Block neodymium magnet chattering. That’s simulated by Matlab software. The bad effect is reduced by exponent reaching law, but it’s not a control law resolving chattering. So the advantage of fuzzy control is analyzed and it’s applied in modern AC variable speed control. Fuzzy control is not completely dispensable to the accurate model of PMSM.
　　Moreover, it can overcome the influence of nonlinear factor. Furthermore, it’s with fast reaction, insensitive to disturbance and it doesn’t need online identification. The chattering is cleared by expert experience, thus resolving the harm brought by chattering. Because the strong robustness to changeable parameters and disturbance, the sliding mode variable control combined with the fuzzy control will be widely used in AC motor variable speed control system. It can resolve the problem the traditional control can’t do, especially for multiple input, multiple output, nonlinear and strong coupling in time varying system. The control way above is used in modern times, the http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php DSP is the result of microelectronics, digit signal process and computer technique. In servo control field, modern control theory with full digital control technique is the essential way for high performance servo control system. For the high speed calculating ability and particular hardware structure, DSP have taken place of computer and single-chip computer in many application systems. After learning the material about TMS320C2000 produced by TI company, the space vector control technique is studied by using TMS320LF2407A to design the hardware test platform. It provides the application software called CC to the C2XX integrated environment. The program is compiled by C language in this environment.The programs includes initial program, main cycle program, overflow program of magnetic field oriented control ,voltage and current sampling ADC interruption subprogram, PID control and fuzzy sliding mode control program. After the test, it can be applied in pratical projects.

Study on Permanent Magnet Synchronous Motor Drive System in Electric Vehicle Application

　　Study on Permanent Magnet Synchronous Motor Drive System in Electric Vehicle Application
　　This dissertation is devoted to the study on permanent magnet synchronous motor (PMSM) drive system for electric vehicle(EV) application.Based on TI company DSP special-designed for motor control on TMS320LF2407A designs and Ball Neodymium Magnets develops a full-digital PMSM vector control system,and both the software and hardware of the system are accomplished.Firstly,the theory of vector control on PMSM has been studied further deeply,the Maximum Torque Per Ampere control strategy in constant torque region and the field weakening control strategy in constant power region are analyzed.This paper presents an algorithm of interior permanent magnet synchronous motor in the field-weakened region. By combining closed-loop control using the output voltage and feed-forward control with the pre-calculated tables,the proposed strategy can achieve fast dynamic control as well as parameter insensitivity in the field-weakening region.Secondly,the Principles structures and the realization of the software and hardware of the control system are introduced.In the hardware of the system,the control circuit and the main circuit design are discussed thoroughly.With assembly language,dual close loop (speed and current) vector control strategy has been realized on the hardware system http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php designed above.The flow charts of main program and PWM interrupt service routines are given.In order to unite all the variables in the program,scaling is used.Thirdly,SVPWM modulation is discussed thoroughly.Voltage using efficiency of accumulator in EV has been improved by the design and realization of software SVPWM, and the harmonic of modulate voltage has been decreased.Finally,the experiment has been done for the driver which design in this paper. Results of the experiment indicate validity of the field-weakening method which introduced in the paper.

Research on Harmonics and Its Influence of Permanent Magnet Synchronous Motor

　　Research on Harmonics and Its Influence of Permanent Magnet Synchronous Motor
　　The harmonics question is the electric machine field important issue. Nowadays, because electric machine performance has been requested to enhance and electric machine’s structure especially in permanent magnet electric machine is complicated, the problem of harmonics has been aroused people’s interest generally. At the same time, with the electric machine’s technology rapid progress, people make some unprecedented progress in the harmonics analysis and suppresses the technical aspect . This topic is the research on harmonics and its Ball Neodymium Magnets influence of permanent magnet synchronous motor, which lies in the torque ripple and the electromagnetic noise with emphasis.
　　First the text make multianalysis on torque ripple reason. It relates to designs, the electric machine s’ structure and the processing craft with the machine main body, also with movement way, Even also the drive controller aspect factor. This article key point is the discussion about the torque ripple caused because of the electromagnetism reason.Next introduction about finite element analysis basic principle of torque ripple and the finite element analysis using the ANSOFT software to two electric machine, and tests confirms. How does in which including carrying on subdivision and the time length of stride selection for enhancing to calculated value precision ,contrasting of the electric machine in ANSOFT in the input voltage for the sine and the non-sinusoidal time torque ripple, it educe http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php superficial type permanent magnet synchronous motor the fractional slots and the integral slots’ pulsating number transferred in week-long time in the rotor, and the fractional slots superiority. And analyzing the torque ripple contrast under other pole/slots ratio and the machines’ parameter produces to the influence about the torque ripple including air-gap length, pole embrace、top rake、notch width.Finally from electro-vibrating classified、the radial force computation、the radial force vibrating and noise-radiation aspect. this article has carried on the analysis to permanent magnet synchronous motor noise, coordinates the comparison and the experiment extremely including the different pole/slots ratio confirms, and analyzed has calculated the electric machine parameter to the electromagnetic noise production influence.

Direct Thrust Control of Permanent Magnet Linear Synchronous Motor Based on Sliding Mode Variable Structure

　　Direct Thrust Control of Permanent Magnet Linear Synchronous Motor Based on Sliding Mode Variable Structure
　　Direct torque control has been applied to linear motor, namely direct thrust control (DTC). DTC technique is a further expansion area of the direct torque control. With the development of power electronic technology, the appearance of novel power electronic devices and various high performance and lower price permanent magnet materials, Block neodymium magnet permanent magnet linear synchronous motor (PMLSM) direct driving system has many advantages over rotating motors and other linear motor.Firstly, according to the mathematical thrust model of PMLSM, the basic principle and implemental method of DTC are discussed. Thrust and flux are researched theoretically. The simulation model for PMLSM drive based on DTC is set up. Simulation results show that it has fast response characteristics, but the disadvantages are serious thrust and flux ripples.Secondly, in order to minimize thrust and flux ripples of conventional DTC drive, this thesis presents two control methods based on space vector modulation (SVM). One is predicting the next PWM period’s flux amplitude to control the thrust and flux to resist motor nonlinear, uncertainties such as variable parameters and load disturbances. The other uses the sliding mode variable structure controller (SMVSC) to control them. Two simulation http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php systems are set up, the simulation results show that both systems using SVM can keep fast response characteristics of the conventional DTC which apparently reduces the flux and thrust ripples. Furthermore, under the same conditions, SMVSC can produce small thrust ripple than the other two DTC systems and it has high robustness.Finally, different control strategies are compared by simulation. The simulation results show that using predicting PI controller, the thrust ripple is 8.9%, and using SMVSC, the thrust ripples is 4.1%. The proposed control system not only keeps fast response, but also has more robust. At last, experiments of PMLSM control system are conducted.

Research of Key Technologies for NdFeB Permanent Magnet Integrated Starter Generator for Vehicle Applications

　　Research of Key Technologies for NdFeB Permanent Magnet Integrated Starter Generator for Vehicle Applications
　　Study on fundamental principle of elertrical system on vehicle, performance characteristic of permanent magnet matiarial and the winding theory for novel current machines. Centrifugal type NdFeB integrated starter alternator which has double armature winding is proposed based on the analysis of engine and transmission on 14V power system.neodymium prices A centrifugal rotor which NdFeB is pasted at flywheel interior is designed after couting electromagnetism parameter and structure paramater, Triphase starter’s winding and single phase generator’s winding are nest parallelly different deep stator slot, and they used communally permanent magnet matiarial.Fundamental principle of start is analysed, controller which be formed of integration chip MC33035, power component PSMN008 and discrete electronic component.The mathematical model of the integrated starter alternator is presented and its corresponding simulation models and programs are got using a toolbox of MATLAB named simulink. The simulation results proclaim that control system scheme is feasible.Fundamental principle of generate electricity is analysed .A regulator circuit consist of benchmark circuit, compare circuit, http://www.999magnet.com/products/142-neodymium-prices trigger circuit for four-phase half-wave commutation circuit is designed. Selection of sampling capacitance and the influence of accumulator is analyzed through the protel and simulink in purpose to seek rationale elctronic component parameters.Flywheel, generator’s rotor, starter’s rotor are designed for oneness. NdFeB permanent magnet integrated starter alternator which could start instantly engine and output DC voltage stabilize at variable speed solves vehicle to output voltage stabilize at variable speed and variable load.

Research on a Single Winding Bearingless Permanent Magnet Slice Motor

　　Research on a Single Winding Bearingless Permanent Magnet Slice Motor
　　The bearingless PM slice motor utilizes the bearingless technology to realize the radial suspension, and achieves the suspension of the other 3 freedom degrees by the reluctance force. It has good performance including dependable capability and has high efficiency on axis direction and so on. It is a new high-integration magnetic suspension motor which has a good application prospect in the fields of ultra-pure driving including biochemistry, medical treatment and semiconductor industry and so on.The former prototype of bearingless PM slice rubber magnetic sheet motor utilizes two windings to drive the rotation and suspension. It has disadvantages including complex structure, serious flux leakage, and reduced dependability due to feasibility of short circuit between two windings.
　　In this paper, a bearingless PM slice motor based on the single-winding structure is researched. It utilizes only one winding to realize the rotation and suspension together, and compensates for the above shortcoming of the dual-windings bearingless PM slice motor.In this paper, the basic principle and realization of the single-winding bearingless PM slice motor is researched. First, a concept of current components superposition is proposed, that is, winding current is considered to be made up of two components including torque component and suspension component, then the suspension force and torque model based on the three-phase restrict of the current components are deduced , and corresponding control strategy is introduced on this basis. Second, the universal model of the suspension force and torque in the motor is deduced when each winding current is considered as a free variable, because the addition of each phase current in the single winding bearingless PM slice motor dispense with the zero, and then, the winding current model and control strategy is researched based on the universal model with power optimal constraint in each winding. Then fault-tolerant capacity based on http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php the universal model of the suspension force and torque is researched when one of the windings is disconnected, and the fault -tolerant model is deduced and the corresponding control strategy is also introduced. The above three mathematical model are proved by finite element analysis.According to the characteristics of single-winding structure, a new power system design based on the H bridge power topology is used, the hardware and software system of the digital signal processor (DSP) are also designed, based on above, a prototype of single winding bearingless PM slice motor is designed and produced. A series of suspension experiments are operated on the prototype motor to validate the control strategies researched in this paper. Experiment results show that the prototype motor can be suspended at 5 freedom degree and operate when one of the windings is disabled.

Calculation and Analysis of Permanent Magnetic Coupling Losses

　　Calculation and Analysis of Permanent Magnetic Coupling Losses
　　Permanent magnetic coupling are composed of two parts: a disc with containing a number of embedded magnets of alternating polarity. These are magnetized in the axial direction. The opposing shaft is connected to a pair of steel discs that have a simple copper sheet attached to the inner surfaces. The principle of operation itself is relatively straightforward: if the magnet disc has a velocity relative to the copper sheets , a current pattern will be produced in the copper discs. This current distribution will result in a circumferential force such that the copper sheet will endeavor to catch up with magnets. The normal operating torque will result in a small slip speed between the two halves of the coupling. An axial force is also present between the copper and magnets discs during normal operation which is a function of the slip speed of the coupling. The magnetic Block Ceramic Magnets coupling offers some benefits of requiring no electrical contact , being reasonably tolerant of misalignment and serving to protect the motor when excessive loads or jammed load occur.The analysis of permanent magnetic coupling can utilize finite element method.
　　This method is precise but also time consuming. Otherwise, there is another way to do it. This is a simple linear analysis based on a layer theory approach. This method was used extensively in sixties and seventies for the analysis of linear induction motors. It accommodates the eddy current patens in the copper sheets in a relatively straightforward fashion and is ideally suited to this type of coupling because each layer is homogeneous. The normal equivalent-circuit based approach would be difficult and inaccurate for this type of device. The model of permanent magnetic coupling is based on this layer theory approach which historically was developed to examine the behavior of linear machines. These type of machines commonly incorporate a sheet copper secondary similar to that used in the eddy current coupling. The model assumes that each permanent-magnet disc in the coupling is faced by a copper/steel sheet on either side. Any further magnet discs are then considered to be identical and therefore all force components should simply be multiplied by the number of additional magnet http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php discs.This article consists of six parts shown as followed:(1) IntroductionThis part introduces permanent magnetic coupling briefly, the development situation, the development trend, and research contents of this article.(2) Summary of permanent magnetic couplingThis part introduces the structure, working principle and merits of permanent magnetic coupling. Classify magnetic coupling, compare with hydraulic coupling, variable frequency drive. Then introduces different types of permanent magnetic coupling.(3) Eddy current and lossUtilizing layer theory to simplify permanent magnetic coupling, establish the linear rise layer model of permanent magnetic coupling. Calculate eddy current, flux density and loss. Utilizing finite element method software ANSYS to analysis permanent magnetic coupling.(4) Temperature analysisUtilizing finite element method to analysis temperature distribution, calculate efficiency of heat conduction, heat convection.(5) Torque and axial forceUtilizing linear rise layer model of permanent magnetic coupling to calculate torque, axial force and working efficiency.(6) Conclusion and prospects In this part conclusion of this article and prospects of the study in the future are given.

A Controlling Method of Permanent Magnet Synchronous Motor Using a Hall Sensor for Hybrid Electric Vehicle (HEV)

　　A Controlling Method of Permanent Magnet Synchronous Motor Using a Hall Sensor for Hybrid Electric Vehicle (HEV)
　　China has been one of the countries which hold a big number of automobiles in the world. The oil used by the automobile is increasing rapidly. The pollution of environment caused by tail gas is increasingly serious. The most practicable solution is that invent a new green environmental protecting automobile, therefore the hybrid electric vehicle comes into our eyes. According to the estimation of experts, 10% to 30% oil can be saved using the hybrid electric vehicle comparing with the normal automobiles. It is obvious that there is considerable practical Block neodymium magnet significance to expand the hybrid electric vehicle. The hybrid electric vehicle technology of China has achieved lots of success though starting is late.
　　The hybrid electric vehicle technology of China is developing rapidly now. The power motor system for vehicle is the key part for the power system of the hybrid electric vehicle, the electric power system and the solution of the oil pollution and so on. The controlling method of PMSM using a Hall sensor for Hybrid electric vehicle is a new controlling method, which aims at the core PMSM controlling technology of the hybrid electric vehicle. The intention is both reduce the cost of the system and improve the controlling accuracy of the PMSM. The controlling method of PMSM using a Hall sensor for Hybrid electric vehicle has applied for patent. The invention belongs to an electrization mechanism field, in particular to a controlling method of PMSM using for Hybrid electric vehicle.The power motor system for vehicle is designed in specialty for hybrid electric vehicle which is powered by the system. Due to relative complicated working circumstance and startup demand of heavy torque of hybrid electric vehicle, the motor and its controller have to meet the these demands that: relative accurate controlled resolution, fast response speed, widely range of speeds of rotation and timely switchover between electromotion circumstance and dynamoelectric circumstance. It is necessary to use PMSM as http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php a power motor of hybrid electric vehicle because of the demands above mentioned.The hall sensor can provide a resolving capability of 60 electric angles only, but the accurate control of the PMSM demands a consecutive angle signal. Therefore using hall sensor as a control signal directly can satisfy the control demand of the permanent magnet brushless motor but can’t satisfy the control demand of the PMSM. To implement the accurate control of the PMSM, increasing the resolving capability of electric angles is necessary. The common methods to increase resolving capability of electric angles are that achieve the factual electric angle of the running motor by rotary encoder and magslep. It is the most convenient to use rotary encode to calculate the factual electric angle of the running motor. The signals which send by the magslep after processing by the hardware is the same to the rotary encode, but the magslep adopts photoelectric sensor, which can’t endure the adverse environment of the vehicle. The cost of the magslep and its hardware is also too much. In general adopting the rotary encoder is a common method of the hybrid electric vehicle. The whole cost is about 3000 yuan.The patent technology adopts three phases signal of the hall sensor, which takes the rising edge and the trailing edge of the three phases signal as the input signal frequency of the digital phase-locked loop.
　　The signal inputs the digital phase-locked loop. One degree resolving capability can be achieved if the digital phase-locked loop adopts 60 frequency doubling. Half degree resolving capability can be achieved if the digital phase-locked loop adopts 120 frequency doubling. Adjust the output signals of the angle by the rising edges of the three phases signal of the hall sensor. We estimate the factual electric angle of the running motor adopting digital method making use of the high-speed computational capability of the DSP with the hall sensor which is often used in the permanent magnetic dc brushless motor. The cost is less than 100 yuan and the reliability is excellent because of using the mature technology. The cost can be greatly reduced and improve the reliability of the PMSM controller in the http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php way.The paper expatiates mathematical model and primary controlling methods of PMSM, analyzes basic motion control manoeuvre of PMSM and the PMSM controlling technology project using HALL sensor. Finished the software system and hardware system of the motor controller and analyzes the experiment results. Complete the PMSM controller basing on MotololaMC56F8367. Explain the design methods of controlling circuits and EMC of the scales about the hardware. Basing on the hardware, realize the patent technology that the controlling method of PMSM using HALL sensor for vehicle by software. The software is compiled with C language and assemble language.The motor runs all right after adopting the patent that the controlling method of Permanent Magnet Synchronous Motor using a Hall sensor for Hybrid electric vehicle. Comparing with the method using a Hall sensor signal directly, the resolving capability of the electric angle is improved from 60 degrees to 1 degree, so the control accuracy is improved greatly and the current picture of the running motor is also greatly improved. It is believed that the patent technology can achieve a better control effect with the improvement of the software system and hardware system.

Optimization Design of Rare Earth Permanent Magnet Synchronous Motors

　　Optimization Design of Rare Earth Permanent Magnet Synchronous Motors
　　Rare earth permanent magnet synchronous motors(REPMSM) have brilliant market future with features of high density, excellent efficiency, low operation cost, efficiency of conserving energy and good reliability. How to meet a motor’s Ball Neodymium Magnets technical requirement and reduce cost is a target of designers and enterprises. According to characters of REPMSM, this paper aims at optimization design and developing a CAD system for REPMSM.The actuality and development of electric machine CAD technique and optimization design are introduced. The performance peculiarity and design method of REPMSM are analyzed. Some key problems are discussed including establishing a motor mathematical model, choosing an optimization algorithm, disposal of discrete variables and interface software part between motor design computing program and optimization program, and so on. A genetic algorithm(GA) is applied to optimization design of REPMSM. The result of an optimization example reveals that GA is a wise choice to optimization design of REPMSM.A CAD system of REPMSM is developed by Borland C++ Builder 6, which can run on the platform of http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php Windows. The CAD system based on engineering database is developed according to software engineering ideas of modularization and integration. The software gathers the function of analysis design, optimization design and some aided function forming into a whole motor CAD software. The paper introduces the function of every part of the CAD system. How database technique is applied to this CAD software is stated. The data storage and fetch with automatic input and output file formed are realized in the system by database management system. The result of computing instances shows that the CAD system can achieve the goal to reduce product cost, improve product quality and shorten period of development.

Study of Transverse Flux Permanent Magnet Linear Machine and Its Drive

　　Study of Transverse Flux Permanent Magnet Linear Machine and Its Drive
　　The linear motor is a sort of transmission system that transfers electric energy to linear motion directly and it has been applied in the fields of industry and military affairs for its favorable features of simple structure, no centrifugal force, etc. Especially the transverse flux permanent magnet linear machines (TFPMLM for short) have shown a brilliant prospect in low speed, high torque systems with special configuration and large thrust force. As the TFPMLM isn’t mature and there are still a lot of aspects to study, it’s necessary to develop a further research on it.neodymium prices The research work is firstly focused on some basic problems. The mechanism of the cogging force is analyzed and its period is also studied. The principle of force magnification is then given. By introducing a so-called equivalent PM current a model is proposed for predicting TFPMLM’steady state performance including the saturation effect.The magnetic field is generally analyzed with three dimensional finite element method and the view is put forward that the 3D magnetic field in the TFPMLM can be achieved by modifying the axial field and the radial field. The characteristics of the cogging force, no-load flux linkage and force vs. displacement are also worked out based on it.Aimed at the problem of a large http://www.999magnet.com/products/142-neodymium-prices d-axis current, the method of commutation advance angle control is studied. It proves that this method can decrease the hysteretic current effectively and hence improve efficiency. A circuit wholly with hardware is designed and the open loop control has been put into practice.The elementary experiments have been carried out. The results accord with that of simulation, which verifies the validity of finite element analysis in the prediction of the performance of the TFPMLM.