Studies of Electric-drive Control System for the Two-wheel Electric Vehicle

　　Studies of Electric-drive Control System for the Two-wheel Electric Vehicle
　　Aiming at the Rare Earth Permanent Magnetic (REPM) brushless synchronous motor (SM) of a two-wheel electric vehicle, two kinds of control technologies are studied separately under sine-wave and square-wave working modes. Based on a comprehensive analysis of the working principle, speed regulating control method and characteristics of the sine-wave and square-wave brushless motors, the drive system construction and control circuit design of both a Block Ceramic Magnets 36VDC electric bicycle and a 96VDC electric motorcycle are proposed in this paper.In this paper special integrated intelligent chipsets together with cheap EEPROM are chosen as the core control unit, and steady SPWM pulse signals can be derived to construct a 36VDC sine-wave drive system through this technology. The peripheral circuit is simple and concise in comparison with analog system; it can also prevent the unsteady situation of traditional SPWM signal generating method through microprocessor program. Besides, special PWM regulating chipsets and logic hardware elements are used to construct a 96VDC square-wave drive system, which adopts a wide-range input voltage switch power supply to provide power supply to the system, and brings negative off-current feedback into the brushless motor drive system, in this way the reliability of a high-power square-wave drive system can be improved, and the prototype system is steady with a 30A load current at most.Through comparison of the above two system test results, it can be concluded that: for brushless REPM synchronous motors with the same structure, both sine-wave drive system control technology and square-wave drive system technology have advantages and disadvantages at the same time. Sine-wave drive system adopts variable frequency http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php speed regulating method, thus the motor is steady, and when weak magnetic speed regulating method is used, the motor can also operate with very high speed and constant power, but it’s prone to out-of-step; While the square-wave drive system adopts PWM voltage regulating and speed regulating method, thus the motor has better control characteristics, harder mechanical characteristics and a bigger startup torque. The vehicle can speed up very quickly,

Rearch on Implementation and Fault Diagnosis of Doubly Salient Starter/Generator Control System

　　Rearch on Implementation and Fault Diagnosis of Doubly Salient Starter/Generator Control System
　　The technology of starter/generator is an important direction of the development of motor and power generation technology. 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. DSES/G and DSEG have begun to be researched to use in aero and Block Ceramic Magnets wind power generation field. Then the demand of its reliability is promoted. However, once the weakest part of the system such as main power converter is in fault, it may bring serious consequence.
　　So the key to improving the system reliability is failures detection and on-line diagnosis.This paper introduces the structure, magnetic characteristics and mathematic model of DSEM firstly, and then analyzes integral working principle of DSES/G. Finally the characteristics of DSES/G are summarized.DSES/G system implementation is an important step of subject research, this paper establishes experiment platform based on DSP+CPLD after completing system model simulation, and proves the validity of the system by experiment research, finally designs the display interface by using virtual instrument LabVIEW.In order to better diagnosing fault of the weakest part of the system, this paper does simulation research firstly, analyzes the situation and impact to the system after different faults. These researches provide theoretical guidance to the on-line fault diagnosis.This paper finally http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php implements on-line fault diagnosis of converter which is the weakest link of the system in starting process and generating process. In starting process, a new method implements open-circuit on-line fault diagnosis through opening un-work arm bridge’s MOSFET by software, and implements open-circuit and short-circuit on-line fault diagnosis through changing the position of current sensor by hardware. In generating process, this paper uses wavelet analysis which has strong analytical capabilities to non-symmetric cycle signal and combines virtual instrument LabVIEW to implementing on-line fault diagnosis of diodes.

Micro External-Rotor BLDC Motor and Its Control

　　Micro External-Rotor BLDC Motor and Its Control
　　BLDCMs have been widely used in the field of aeromodelling with the advantages of small size, light weight, high efficiency and reliability. BLDCMs can be divided into external rotor BLDCMs and inner rotor BLDCMs due to the different structure. This paper designs a type of External rotor BLDCM and the control system.Firstly, the external rotor BLDCM was analyzed from permanent magnet material, magnet.structure, magnetization, winding distribution Block neodymium magnet and pole-slot combinations. The parameters of the motor were calculated according to classical BLDCM design methods and formulas. Meanwhile, in order to validate the rationality of the parameters, this paper also established the finite element simulation model. Based on the finite element analysis, the characteristic and static performance of the motor were acquired, the torque and gap magnetic field were also calculated.Secondly, this paper developed a controller for the sensorless BLDCM based on the MCU Atmega88. The BLDCM control system based on BEMF method was designed. The peripheral circuits, power circuits and BEMF detection circuit of this system were introduced in detail. The whole design and the main program flowchart were expounded. A few primary flowchart such as pulse detection, self-starting, sensorless operation were also expatiated.Lastly, the external rotor BLDC motor http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php was carried on experiments including unloaded state, loaded state and gradually loaded state, etc. The experiment results validated that the whole system worked steadily and reliably which supplies the reference for the following research work.

鱼雷推进用无传感器无刷直流电机动态性能分析

　　鱼雷推进用无传感器无刷直流电机动态性能分析
　　Due to high efficiency, excellent speed-adjustability, and high reliability, the high-power permanent-magnet brushless DC motor drive system has applied in the domains as ships, aircrafts and so on, where the attention is firstly paid to the running efficiency and feasibility of drive system.The dissertation proposes a speed-adjusting controller which applied to a large power capacity rare earth permanent magnet sensorless brushless DC motor (SLBLDCM). The dissertation discusses the stepless speed-adjusting technic about torpedo drive motor, and the developing state Ball Neodymium Magnets of BLDCM .Considering the feature of the torpedo driver motor and the engineering application, the system scheme, the hardware and software of SLBLDCM are designed. Then, the operational principles of BLDCM and the PWM speed-adjusting theory are analyzed. Additional, the operational theory of the 2-phase feed up, all bridge star style 3-phase 6 states BLDCM system with 3 pair poles are analyzed. The mathematics model and the Stable state model of BLDCM system are abolished.Basing on key-technology issues which are faced in the course of BLDCM control system ①rotor position detection Basing on other approach to detect rotor position, we design a new approach to compensate larger scope phase and a way to detect rotor position.②starting technique,basing on the http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php very difficult examination problem when the EMF of SLBLDCM is lower,we proposed a starting technique, which is enhance the frequency and the voltage simultaneously .And this method has solved this problem well. ③torque ripple, we analyse the torque ripple due to the exchange phase and the effect of the pulse Width Modulation, and we suggested a new PWM modulates method (PWM-ON-PWM) .Through to calculation of torque ripple under this kind of pattern modulation We obtains this is one very good solution this question PWM modulation method. Based on the above research, hardware and software of a control subsystem are designed ,which use the TMS320LF2407.

Research on the Control System and Path Planning of Underwater Ship Hull Cleaning Robot

　　Research on the Control System and Path Planning of Underwater Ship Hull Cleaning Robot
　　The subject is one of Heilongjiang major science and technology projects. This paper introduces the structure of the Underwater Ship Hull Cleaning Robot. The control system of the robot is completed and the path planning is proposed in the paper. Moreover, the aptitude test is proceeded after all.Firstly, the development of the hull cleaning technology and the application of climbing robot is introduced. According to the working environment, a reality structure scheme using permanent magnet adsorption and twin pedrail type structural cleaning robot is put forward. Permanent magnet structure, driving chain and cleaning devices are researched and designed. Drive style of Cast Alnico Magnet cleaning robot is designed and servo motors are selected. Therefore, collectivity design on The Underwater Ship Hull Cleaning Robot is finished.Secondly, the cleaning motors are selected. Using the direct torque control method, cleaning motors are emulated based on their mathematical model through MATLAB 7.0.1.Thirdly, the controlling system including super computer and subordinate computer based on AT89C51 is designed. According to controlling function of subordinate computer, the controlling circuit and interface circuit of servo motors controlled and serial port communicating circuit are designed and built in the robot reality. Super computer carry mainly through keyboard scan and number showing design. The cleaning robot is controlled by serial port communication and robot’s working state is showed through number pipe. Based on C-language, the control software about super computer and subordinate computer are designed as well.Fourthly,
　　this paper gives concept of covering-path planning, its mathematics description as well as its designing method about full covering-path planning. The paper also describes several kinds of performance functions of covering-path motion. According to that, we designed the complete coverage path planning method based on biologically inspired neural network for cleaning robot.Finally, aptitude test of the cleaning robot is developed. The test result indicates that The Underwater Ship Hull Cleaning Robot has doughty burdened capability and balanced moving and adjusted http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php velocity, and better power against turning over and correcting decline. Every capability guideline meets the designing requirements well.The brand-new scopes is inaugurated as the development of The Underwater Ship face Cleaning Robot can not only increase cleaning efficiency and cleaning roboticized level, but also can reduce manual work intension and pollution. Therefore, the development of the Underwater Ship Hull Cleaning Robot has important meaning.

Preparation of Coated Nanocomposite Magnetic Powders and Investigation on the Densification by SPS

　　Preparation of Coated Nanocomposite Magnetic Powders and Investigation on the Densification by SPS
　　Nanocomposite magnets consist of hard and soft magnetic phases. A high remanence and large maximum magnetic energy product would be obtained because of the exchange coupling effect of the hard and soft phases. In addition, Nanocomposite magnets have excellence in low rare-earth concentration, low cost and high use temperature. So nanocomposite magnets become a promising candidate of the fourth generation permanent magnet after the third generation magnet of Nd2Fe14B. In this thesis, the bulk nanocomposite magnets are prepared by Alnico Magnets sonochemistry, high-energy milling and spark plasma sintering. First, the preparation of the nano-iron particles was investigated. And based on the results, the coated nanocomposite magnetic powder consisted of hard and soft particles was successfully prepared by sonochemistry. The final work was focused on the densification of the coated nanocomposite magnetic powder by spark plasma sintering. The study emphasis was laid on the dependence of properties and microstructure of the magnets on the process of sintering, the content of soft phase and high-energy ball milling before sintering.The preparation of nano-iron and coated nanocomposite magnetic powder by sonochemistry and the mechanism of coating were systematically studied by means of SEM, TEM, IR, XRD and EDS. The optimum preparation condition by sonochemistry was determined. Coated nanocomposite magnetic powders were prepared through the use of sonochemistry for decomposing carbonyl iron in decane solvent at -3～0°C in Ar atmosphere http://www.999magnet.com/products/108-alnico-magnets for 2h～3h with the sonochemical power of 120W. The hard magnetic particles are well coated by nano-iron particles. In addition, hard magnetic powder used for coating needs to be carried out high-energy milling for becoming fine. On the condition of certain Ratio of grinding media to material speed of rotation, hard magnetic particles became finer with the time of milling. But after milling for 8h, the hard magnetic particles became coarser. As a result, it is determined that the time of milling for hard magnetic powder is fixed on 6h.Bulk two-phase nanocomposite magnets densified by spark plasma sintering have

Corrosion Resistance of Electroless Plating Ni-P Alloy on Sintered NdFeB Magnets

　　Corrosion Resistance of Electroless Plating Ni-P Alloy on Sintered NdFeB Magnets
　　NdFeB type magnet, which possesses excellent magnetic properties, is a new type of permanent magnet material, which is discovered by Japan in 1983. Permanent magnetic material is rapidly widely used in the electronics industry, communication, information, defense, medicine and health, environmental protection and oil fields etc. in a short period of several decades because of its rich source and low price. But the strong chemical activity, poor anticorrosion and easy being oxidized of NdFeB magnets material seriously affect its scope of application.To improve the corrosion resistances of NdFeB type magnets, lots of attempts have been done, such as enhancing the intrinsic corrosion property of material by the addition of elements and applying various protective coating on the surface of the magnets. Among all surface coatings amorphous Ni-P coating, which possesses neodymium standard state more mechanical, magnetic and anti-corrosion performance over the crystal materials, may be one of the most excellent. In this thesis, reports on corrosion mechanism and anticorrosion process of NdFeB permanent magnet are reviewed. On this basis, electroless deposition of Ni-based alloy was employed to NdFeB magnet to enhance its corrosion resistance.Surface loose, lots hole and Nd element very active(E=-2.4eV) and vivacity of the sintered NdFeB permanent magnet, the pretreatment processes and apply plating process which is difficult to apply plating whether in acidic or alkali electroless plating bath, it is the key to get ideal coating that alleviate corrupt.
　　The optimized pretreatment processes include burnish process, plug process, oil removing process, picking and activation process, and precoppered process. Oil-removed by supersonic, and acidwashing must be carried in 30-40mL/L of nitric acid (65%) with the addition 0.5g/L of thiourea, in pH adjusted to 4–5 by ammonia liquor, in limited time of 20-30s.Experiments find that we can’t direct plat with acidic solution in the sintered NdFeB magnets’surface, otherwise magnet corrosion. In this paper, the composite deposit coating include first pre-copperplating coating, second litmusless plating coating and last alkaline plating coating. The composite deposit coating has a better corrosion resistance and little porosity than ultrasonic electroless plating. The pre-copperplating can http://www.999magnet.com/products/112-neodymium-standard-state improve coating adhesion strength and corrosion resistance, effectively reduce the porosity of the coating. Microstructure analysis performed by means of SEM, the results show that the coating and magnet surface has a stronger adhesion, and the same size of cellular particles composite of the coating.The results have shown that the composite complexing agnet has more stability solution than single complexing agnet, and has a higher deposit rate. So the composite coating has a more compactability and fewer porosity.The experiment indicate that the alkaline electrolessly plating Ni-P deposit ,which were prepared for the sintered NdFeB magnets under 40 kHz frequency ultrasonic field, has better fine microstructure and adhesion force than the Ni-P deposit without ultrasound field.

Research on the Signal Detection Technology of the Servo System of High-Response Linear Motor

　　Research on the Signal Detection Technology of the Servo System of High-Response Linear Motor
　　Linear Motors are novelty motors that can realize direct drive and convert electricity energy into linear movement without any medium machine. They have wide application foreground in many fields such as high speed and high precision numerical control, precision measurement because of their advantages of high speed, high precision, big thrust force, long stroke and fast response.In the control process of Linear Motors, the acquisition of feedback signals is Alnico Magnets very important. So the research involved signal detection has been a focus.Firstly, the paper gives an introduction to the structure and basic theory of the permanent magnet synchronous linear motor (PMSLM). And also the difficulty of control system is discussed based on the control method of PMLSM in this paper. Then position detection technology, current detection technology, hardware system and software design is discussed.Because of the special structure characteristic of the PMSLM, high resolution linear encoder was adopted as detecting component. And subdivision technology was used to improve the detecting resolution. At the same time, the position collecting circuit design based on the chip LS7266R1 is proposed. The approach based on electrical current Hall device is used to detect electrical current, with simple installation and the results meet to the requirement. And then signal detected is converted into voltage signal by special electrical circuit. A/D converter model was designed in order to sampling the converted voltage signal, which was based on chip MAX125 and achieved very high accuracy. In addition, protect circuit was designed. When there is fault in the circuit, it will close off the control signal and http://www.999magnet.com/products/108-alnico-magnets send out an interrupt request to Digital Signal Processor(DSP). Interference was considered when designed hardware and software, so the reliability and stability of PMSLM were improved.Finally, controlling boards and software were debugged. And experiments about the performance of the linear motor servo control were done. At last, the paper analyzed the experiment results and presented some problems about the linear motor servo system and the further research work.

The Development of Embedded and Networked Control Platform of AC Servo Driver

　　The Development of Embedded and Networked Control Platform of AC Servo Driver
　　Permanent Magnet Synchronous AC Motor(PMAC) is widely used in modern industrialization for its outstanding performance. With the improvement in the performance of Digital Signal Processor(DSP) and Field Programmable Gate Array(FPGA), Motion control system is enhanced too. Permanent Magnet Synchronous AC Motor controller is developing towards high-speed, high-precision, full digital and network.According to the character of the AC servo system neodymium prices and the engineering application requirement, with the special requirement of Computer Numerical Control system(CNC), a platform of AC servo driver is developed in this thesis. The platform is based onμC/OS-II embedded real-time operation system, DSP processor, ARM(Advanced RISC Machine) processor and FPGA. Previous foreground and background structure of AC servo driver is adopted in the software platform. It has some disadvantages, such as: high dependency between modules, hard to extend and coordinate. So the real-time operating systemμC/OS-II is introduced in this thesis. It has many advantages, for example: improving real-time performance, making software structure legible, easy to extend, design and debug. The processors with high performance, realiability and integration are adopted in the hardware platform to improve control system performance and meet the demand of AC http://www.999magnet.com/products/142-neodymium-prices servo system. The main works of this thesis are listed as follows:1.the hardware of AC servo driver is designed, the structure of hardware platform is DSP, ARM and FPGA.2.Modular design of software is proposed andμC/OS-II operation system is transplanted to DSP processor which is the kernel Processor.3.Ethernet communication and personal-computer interface is carried out by ARM.4.The hardware logic circuit is implemented by FPGA, peripheral and digital interface is completed.

Research on Robust Control for Linear Servo System on CNC

　　Research on Robust Control for Linear Servo System on CNC
　　After the period of 90’s, because of the development of computer science, micro-electronics, and modern control theory, Electrical Machinery and its interrelated subjects develop swiftly and violently. It is feasible and inevitable that digital control method has been taking the place of analog control method in this field. At the same time, the technology about the linear motor is widely used in the precise location field. Especially, with there quirement of the digital controlled Cast Alnico Magnet machine tools increasing, the hyper speed, the hyper precision, the hyper reactivity, what is called zero mechanical gearing control theory, are easy to put in practice for the linear motor’s servo system. The permanent magnet linear synchronous motors (PMLSM) 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 PMLSM has been rapidly developed and widely applied in recent year.The robust control theory has studied system’s uncertainty specially to the system the influence, is suitable specially for the CNC machine tool permanent magnet linear synchronous servo system. This article first elaborated the robust control theory and the linear servo system vector control theory, then has designed the double closed loop robust controller for the linear servo system. Has http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php designed the PI electric current controller in the electric current circle, but has designed the H_∞speed controller in the speed circle, and used LMI (linear matrix inequality) method to carry on the solution .the simulation results show that the design of the controller than the method for the Riccati controller has better robustness. Simultaneously has designed the closed-loop pole region disposition robust controller using the LMI method to the linear servo system, designs the controller compared to only uses the LMI method to have the better dynamic performance. After having considered permanent magnetism linear synchronous motor’s model uncertainty, also used the LMI method to design for it has considered the circular closed-loop pole region disposition H_∞robust controller.

Study on Design and Application of BLDCM for Air-condition Compressor

　　Study on Design and Application of BLDCM for Air-condition Compressor
　　Permanent magnet brushless direct current motor(PMBLDCM) has good characteristic such as small inertia,easily controlled ,dynamic function well , therefore it has got extensive use in many field ,such as aerospace, robot, air-condition compressor control machine tool. The subject aimed at the air-condition compressor, has designed the BLDCM and corresponding control system.First, minimizing cogging torque is one of the main concerns of permanent magnet motor. In order to reducing the cogging torque of PMBLDCM , an analytical method, which was based on rubber magnetic sheet energy method and Fourier expansion, was proposed, which can express how to match slot and pole to reduce cogging torque. The research indicated that if the least common multiple between the slot and pole is 2pz, and the greatest common divisor is 1, the cogging torque can be greatly reduced. Being based on the expression,
　　PMBLDCM with similar pole and slot is selected . Further, the effect of pole-arc length on cogging torque is studied and the most suitable pole-arc length can be determined. The validity of the proposed method was verified by finite element analysis.Then, through BLDCM used in the air-conditioning compressor, as well as considering reduce motor’s vibration and the noise, two PMBLDCM were designed, including the 6 pole 36 slot and the multipolar few slot ,such as 8 pole 9 slot motor. With the aid of the Ansoft software ,design indicates that choosing multipolar few slot motor belonging to the approximate pole and slot, further choosing the suitable pole-arc coefficient, can reduce the cogging torque greatly and can reduce motor’s vibration and the noise. Above all, the multipolar few slot motor can be adopted in the air-conditioning compressor.At last,sensorless control technology has been a hot research in BLDCM control domain. This paper introduces the control system design for brushless DC motor based on PIC18F4580, discusses in detail the current http://www.chinamagnets.biz/rubber/rubber-magnetic-sheet.php commutation and motor speed computation, and designs the corresponding software circuit. In order to improve speed control performance of motor, this paper adopts the double-closed-loop control strategy and gives the corresponding implement methods.Designing BLDCM initial data scheme, Ansoft carrying out verification on electromagnetism design , designing PIC monolithic machine controls system are the main parts. Above this three parts, this paper have accomplished BLDCM design and application for air-conditioning compressor.

Manufacture and Properties of Sintered Permanent Magnetic Nd-Fe-B

　　Manufacture and Properties of Sintered Permanent Magnetic Nd-Fe-B
　　The key techniques for manufacturing high performance sintered Nd-Fe-B permanent magnet have been studied in the aspects of process, magnetic aligning and microstructure, in order to improve the magnet quality for its competitive ability in international market and technological added value,and develop the application of the rich resource, rear earth, in our country.A nominal Nd29.51Tb0.4Nb0.06FebalB0.98wt% alloy was prepared by strip casting, breaking, pressing and sintering process. The microstructures of rapid casting strips in different neodymium standard state cooling speed or flake thickness were compared and analyzed. The effects of different breaking process on the magnetic particle size were investigated. The orientations of the magnet pressed in both rubber die and steel die were tested. Further more, the effect of sintering temperature on microstructure and magnetic performance was studied.The results show that (1) the grain of strap sample, with average size 3.428μm, obtained in cooling speed of 2.6m/s was more uniform than that in other speeds, based on the experiment conditions. The flake with thickness of 0.35mm～0.40mm has ideal microstructure, that is, the dominant plate crystal was fine and uniform, and the Nd rich phase was distributed evenly between the plate crystals, andα-Fe dendritic precipitation was inhibited. (2) the particle sizes http://www.999magnet.com/products/112-neodymium-standard-state of the magnet milling by hydrogen breaking process is finer than that of milling by mechanical breaking (3) The orientations of the magnet pressed in rubber die is better than in steel die. (4) the grain size of the magnet sintered in 1055℃was uniform and fine, and the average grain size was about 10μm and Nd rich phase was distributed uniformly, which was the proper sintering temperature to manufacture magnet with less rare-earth element content.The permanent magnet prepared by strip casting, hydrogen breaking, rubber die forming and lower temperature sintering has achieved good magnetic properties: Br=1.463T(14.63kGs), Hcj = 997kA/m(12.54kOe), (BH)max = 419kJ/m3(52.6MGsOe), Hk/Hcj=0.956, and the better stability and square degree. The Nd-Fe-B magnet can provide the market requirement, such as the application of nuclear magnetic resonance.

Study on the Coercivity Mechanism of Nd-Fe-B Melt-spun Nanocrystalline Magnets

　　Study on the Coercivity Mechanism of Nd-Fe-B Melt-spun Nanocrystalline Magnets
　　The reversed magnetization process and the coercivity mechanisms for NdFeB nanocrystalline Rare-Earth permanent magnets are discussed and investigated by comparing the experimental results with calculated ones.Take a isotropic permanent magnet with single axis magnetocrystalline anisotropy for a sphere. Being satuated and removing the magnetizing field, Alnico Magnets all magnetization distribute equably on the upper hemisphere and the magnetization directions are normal to its surface. Divide such a hemisphere into 36 petals alone X axis. Angle this magnet withershins to an angle that is the multiple of 5°, then measure its magnetizing remanent magnetization curves along H direction. A series of magnetizing remanent magnetization curves is obtained.Such measurements is simulated in computer by dividing very petalinto a series of cell with different angles θ to http://www.999magnet.com/products/108-alnico-magnets H and calculating the H(θ)using pinning or nucleation model. It is found that the remanent magnetization curves calculated using pinning model resemble the experimental ones mostly, which confirm the reverse of magnetization is control by pinning.

Research on Adaptive Feedback Control System Based on PWM of Synchronous Switching

　　Research on Adaptive Feedback Control System Based on PWM of Synchronous Switching
　　Synchronous switching, also called phasing switching, is used widely in electric power system to control and reduce switching transients, increase the interrupting capacity of switches, improve the reliability of electric power system and customer power quality. Many people have paid attention to the research and application of synchronous switching.The paper focuses on permanent magnetic actuator of vacuum circuit breaker synchronous operation technology practical problem existing in power system, combining the education department of Sichuan Province important project "Neodymium Magnets Research on permanent magnetic actuator synchronous switching theory and application( Project Number:2005A119)", introduces fuzzy control method to study the vacuum circuit breaker with bi-stable permanent magnetic actuator. It adopts MATLAB related toolbox to simulate and analyze. According to the simulation result, synchronous switching adaptive feedback controller based on PWM is designed.In this paper, it introduces the structure and principle of permanent magnetic actuator at the first.
　　Then the intellectual control technology of vacuum circuit breaker is discussed particularly. As a control object, the bi-stable permanent magnetic actuator is separated into basic principle so as to determine the nature of the whole. The direct-coupled models of magnetic fields for analysis and for calculation are presented. The static and dynamic characteristics of the models and dynamic behavior analysis and matching analysis for the vacuum circuit breaker with bi-stable permanent magnetic actuator are also discussed. For a further study, fuzzy neural network control technology based on synchronized-closing operation of vacuum circuit breaker is analyzed and the research http://www.999magnet.com/products/110-sintered-neodymium-magnets conclusion is used for realizing the synchronized-closing of vacuum circuit breaker in the future.According to the demand of market, the control unit based on single chip microprocessor TMS320LF2407A for intelligent breaker is designed for permanent magnetic actuator of vacuum circuit breaker adaptive feedback controller. The controller has many functions such as protection, control, measurement. The signals of currents, voltages, active power and reactive power are monitored in real time. The control unit can not only control opening/closing operation of circuit breaker, but also has the functions of over-current/under-voltage trip, closing/opening interlock for mal-operation and diagnosis functions.In the end, The paper emphases on the design and introduction of fuzzy controller based on bi-stable permanent magnet actuator of vacuum circuit breaker. The synchronous switching fuzzy control system simulation model is established by using MATLAB. By means of analysis of the system’s final artificial result, it proves the fuzzy control algorithm is effective. Furthermore, some important data are beneficial to further study on synchronized- switching of vacuum circuit breaker and intelligent control theory of vacuum circuit breaker with permanent magnetic actuator.

六相永磁同步电动机特性仿真的研究

　　六相永磁同步电动机特性仿真的研究
　　This thesis chooses the six-phase permanent magnet synchronous motor as the subject to research. First, the control model of Space Vector Pulse Width Modulation (SVPWM) is founded and the simulation model of six-phase inverter is set up by means of the concept of switch function. Second, the mathematical model of six-phase permanent magnet synchronous machine is developed in stationary a-b-c frame at the base of the multi-loop theory. According to magnetic neodymium prices conductance analytical method Inductance is calculated and the expressions of it and inductance leakage is deduced. Finally, the simulation model based on SIMULINK is achieved and the whole system performance simulation respectively on dynamic and steady situation is provided.With advantages such as higher usage of DC voltage, adapt to digital-control and the capacity of building high performance speed regulation system, Space-Vector-Pulse-Width-Modulation (SVPWM) is a better method than Sinusoidal Pulse Width Modulation in field of AC motor speed regulation. SVPWM Control principle and modulation method are analyzed first, then a SVPWM converter model is established and under a simulation example, the results, show that the SVPWM model is more effective in reducing harmony wave.Multiphase motor system is suit for the occasions that require high power and reliability, for example galley, under-ship propulsion system and nuclear power station’s cycle water system, because it http://www.999magnet.com/products/142-neodymium-prices can supply high power, reduce torque ripple and improve the reliability of the system. At present, it has been successfully applied to the six-phase PMSM propulsion system of America army. Based on the actual physical elements, a Multiphase motor State-space mathematical model is established and then according to it the S-Function model is founded. Powered with the converter founded early, the Multiphase motor system is simulated respectively on dynamic and steady situation which including starting and breaking characteristics and steady-state characteristics, the results validate the rationality of the model. On above basis, the fault-operation performance of the system is simulated to demonstrate the system’s speciality of stability.

基于DSP的永磁同步电机控制方法研究

　　基于DSP的永磁同步电机控制方法研究
　　With the development of high performance permanent-magnet material,electric power and electron technique,large scale integerated circuit and compute technique. Many scholars and researchers of home and oversea have attached importance to permanent-magnet synchronous motor(PMSM) because of its small volume,high power density,high efficiency and power factor. During the development of near twenty years,its manufacture have applied to the fields of industry and neodymium prices agriculture and space technology etc. Then, it has important real significance to research in PMSM and its control method further, The paper mainly study in the control way of PMSM.The main contents and innovations of the paper are as follows:1. Analysis of the configuration and characteristic of PMSM and new research findings of scholars at home and overseas. Study on the three transfers of axes in the theory of PMSM control and list the model of PMSM in the two different coordinate systems . Design of the simulation model and simulate it.2. Analysis of the fundamental principle of SVPWM and DTC and design each simulation model of control system based on them. Study on each characteristic http://www.999magnet.com/products/142-neodymium-prices and their difference in the control performance of PMSM.3. Based on the analysis of DTC of PMSM,The paper present two ways to restrain torque ripple which are worked by the selected voltage vector in the transition of the section. Simulation result shows they work well. Study on the the control effect of zero voltage vector in DTC and a modified strategy of DTC of PMSM. The simulation experiment results show that they could restrain torque ripple availably.4. Based on the basic control method,Fuzzy logic control have been used to optimize DTC of PMSM. Design the simulation model of fuzzy logic DTC of PMSM. Simulation result shows fuzzy logic could improve the control performance of DTC effectively.5. Adopt the special chip of TMS320LF2407A to control motor,Design software and hardware circuit of the DTC system of PMSM. This will be a base to study in the future.

The Analysis and Design of AC PMSM Servo Systems

　　The Analysis and Design of AC PMSM Servo Systems
　　The permanent magnet synchronous motor(PMSM), whose rotor is constructed by a kind of rare earth material, such as NdFeB, has appeared since early 1970’s. With the development of the technology of power electronics control, NdFeB material and motor design, permanent magnet synchronous motors get wide applications in many control systems, especially in the Cast Alnico Magnet accurate servo control systems because they have excellent control capabilities, large torque coefficient, small ripple torque, and many other good qualities.This thesis first introduced the development of PMSM and servo control system, and illuminated the mathematic model, rotor field orientation control (FOC) principle of PMSM and the space vector PWM(SVPWM) technology. Then the current servo system and speed servo system were simulated by MATLAB/SIMULINK respectively. The simulation waveforms verified the validity of the entire system design. That supplied a good foundation http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php for the following hardware design, software design and experiments analysis.On the base of principle analysis and simulation experiments, the thesis particularly studied a digital AC servo system for PMSM based on DSP. The hardware structure of the system was introduced briefly and the key design method of software and controller were introduced in detail. Finally, the current, speed and position step response experiments were completed by a PMSM as control plant. The experiments showed the servo control system with good performance and could be applied to the practice.