Research on Electromagnetism of PMBLDCM with Wind-round in Agricultural Vehicle

　　Research on Electromagnetism of PMBLDCM with Wind-round in Agricultural Vehicle
　　The small-scale wind-round DC Motor with minor axis for the used of agricultural vehicle have their own properties, each individual consumes little (less than 300w ) but the quantities of the wind-round are large. So it is very meaningful to reduce the consumption of the small-scale wind-round for improving the construction of modernization and narrowing the gap between our state and developed countries.Permanent Magnet Brushless DC Motor (PMBDCM) is suitable for Cast Alnico Magnet agricultural vehicle by its specific property of more efficient density. In this paper, torque ripple suppression techniques have been studied in details and some novel effective measures have been proposed because reducing cogging force is indispensable for improving the minor axis PMBDCM.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, we could manufacture of the outer rotor PMBDCM to meet the target of cost saving. According to the characteristics of the outer rotor motor mechanical structure and the small-scale wind-round in agricultural vehicle, this paper http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php presents a new technology: the magnetic rotor yoke devices directly build in the wind-round cavity to constitute a new outer rotor to save material and simplify the processing and outside the rotor balancing process. As the process simple, provincial materials, low cost, makes the motor in the agricultural vehicle to promote the application of practical significance. Prototype measured data show the motor has a good cost-effective performance of the advantage of industrial production.

Study of Full-digital PMSM Servo System Based on DSP

　　Study of Full-digital PMSM Servo System Based on DSP
　　AC Permanent Magnet Synchronous Motors (PMSM) servo system is used more and more widely, such as industrial controllers and household appliances.It has been the important domain of the domestic and foreign research and application. Full-digital controlled AC PMSM servo system is the trend, which uses high quality control strategy based on DSP and is greatly neodymium prices convenient to realize intelligent control strategies.The purpose of this paper is to develop an experiment platform of full-digital PMSM servo system based on DSP, which can provide a platform for further research and a choice for cheaper with enough performance project application.Firstly, the general development situation of PMSM servo system is introduced. Then the mathematical model of PMSM is founded. after that the rotor magnetic field-oriented vector control, SVPWM, current circle, speed circle and position circle is analyzed and the simulation research based on Matlab/Simulink is completed, which validates the feasibility and correctness of control theory and provides the theory basis for the realization and debugging of real system.Based on the theory and simulation of the analysis, the full-digital servo http://www.999magnet.com/products/142-neodymium-prices system hardware platform was designed using TI’s DSP-TMS320LF2407A as the control core and intelligent power module IRAMS10UP60A as the power switch unit. The modularization applied in system software and control program was completed in assemble language based on the hardware platform.Finally, the experiment results has been obtained, which indicate that the control system can achieve good dynamic and static drive performances, and which prove that the theories and the simulation analysis are correct and pave the way for future research and application.

On the ISG Controller and System Control Strategy of Hybrid Electric Vehicle

　　On the ISG Controller and System Control Strategy of Hybrid Electric Vehicle
　　Conventional vehicles have been faced with crisis of petroleum and serious environment pollution, and the development of automobiles energy saving and environmental friendly becomes a mainstream of the world automobile industry. The pure electric vehicles are difficult to be widely used because of the limited driving range and high initial cost. The commercialization application of fuel cell vehicles will take a long period of time because the fuel cell technology has not been matured. Hybrid electric vehicle (HEV), which combines the advantages of the conventional automobile and electric vehicle arises and becomes one of the most feasible ways to solve pollution and fuel problems. Integrated starter/generator (ISG) is a key technology of parallel hybrid electric vehicle. Automobiles with ISG having low fuel consumption and emission have become one of the neodymium standard state world-famous advanced hybrid electric vehicles.In the ISG-based HEV, design of motor and its control system is one of the most important works in the design of powertrain. Control strategies are important for the ISG-based HEV to achieve best fuel economy, low emission and good power performance. This paper addressed the problem of selecting architecture and parameters of ISG motor. The motor was designed and the control algorithm was studied. The control system of ISG motor based on vector control was developed. The ISG-based HEV was modeled and simulated by ADVISOR2002. Energy management strategies for the whole system was developed and then evaluated by simulation.The different types of HEV configurations can be classified into three basic kinds: series (SHEV), parallel configurations (PHEV), or a combination of both (PSHEV). ISG-based HEV is a typical kind of PHEV. The ISG system with motor not coaxial with the engine is also called B-ISG system, as the motor is connected to the engine crankshaft by belt drive. The technology of B-ISG is always used in mild hybrid vehicles.
　　In the ISG system where the motor is directly mounted on the engine crankshaft, the motor can have greater power and can be used in moderate and heavy hybrid vehicles. Considering both performance and cost, we select the structure that the motor is mounted on the flywheel output end of diesel engine and then connected to transmission via a clutch. In order to decrease the energy loss in the circuit and the cost of the system, the voltage of the ISG-based HEV is selected at 336 V. The high voltage of battery pack can bring many freedoms to the system design. In this article,In the ISG-based hybrid electric system, the electric machine should be able to work in states of electric drive or power generation. The motor drive system should provide an enough large starting moment, to meet the need of starting and ability of power-assisted. As well, the motor drive system should have efficiency as high as possible and also high reliability. In the hybrid electric power system, the classes of motor usually used mainly include direct current motor, the permanent magnet motor, the induction motor and the switched reluctance motor. After comparison of motors with different structures, the permanent magnet synchronous motor (PMSM) is selected as the electric machine used as the ISG motor. Then, the parameters of the ISG motor were selected with considering of both the performance and control http://www.999magnet.com/products/112-neodymium-standard-state objectives of the In the ISG-based hybrid electric vehicle.The control of ISG motor is a tough task as the motor has to rotate with the engine at the same speed. This thesis studies on vector control algorithm of ISG motor. The control system based on Motorola DSP type single chip microcomputer 568F8367 is developed. The inverter module are mainly composed of six insulated gatebipolar transistor (IGBT), and the space vector pulse width modulation is used to produced three phase alternating voltage, which directly drive the PMSM. The developed control system is tested on the ISG experiment platform, and the control algorithm is optimized using the experiment data. The experimental result proves that the performance indexes are meted.The vector control system much dependence on the parameters of PMSM, such as the rotor position, and complicated coordinate transformation is needed. They are problems to be solved.
　　The direct torque control direct torque control of PMSM is studied. In this control method, field orientation is not achieved by feedback, so the rotor position is unneeded, while fast and reliable torque response can be produced. A simulation model of direct torque control system is developed using the Matlab/Simulingk toolbox and the control performance is studied by simulation results. After analysis of field weakening operation in direct torque control system, an algorithm of field weakening control is proposed and also studied by simulation. The main defaults concerned with the traditional direct torque control system are the large torque ripple, poor performance of low speed region, inconstant switch frequency, etc. The reason of torque ripple is studied and refinement algorithms world wide are reviewed. Finally, the Future research direction is suggested.The rationality and validity of control strategy have great influence on the performance of whole HEV system. The function http://www.999magnet.com/products/112-neodymium-standard-state of control strategy is to coordinated control different subsystems, making them work in optimal states, and rationally control the energy flow of the hybrid electric drivetrain. The design principle of control strategy is to optimize the power performance of HEV, and to achieve a high fuel economy, low emission and low cost at the same time. The development of vehicle control strategy should take in consideration the specific configuration of hybrid electric vehicle, as well as the real drive cycles and different drive patterns.The vehicle control strategy based on the logic threshold control is designed. The control strategy consists of several subroutines, such as the on/off control of the engine, the calculation of engine torque, the calculation of motor torque, etc. vehicle traveling is classified into six typical operation modes. The model of ISG-based HEV is established using the simulation tool ADVISOR 2002, and the developed control strategy is also implemented. The simulation results prove that the ISG-based HEV is better than the conventional vehicle in most performances.Finally, some problems for further research are proposed.

均匀磁场对DNA复制过程的影响初探及其发生装置的设计

　　均匀磁场对DNA复制过程的影响初探及其发生装置的设计
　　With the pollution of electromagnetic fields on human existence environmental aggravating, scientific research are very interest in the possible biological effects of electromagnetic fields on the organisms. As the living environment where people are in the field of diversity, its effect on the biological organisms are very complex, which the effect on the cell cycle by electromagnetic fields is one of the important issues.When osteoblast were cultured and put in different forms of magnetic field,the researchers found that the cell cycle were changed, S-phase percentage were significantly higher as compared with control, but the specific mechanism of the effect on the cell cycle by magnetic field is not clear. The researchers speculate that the cell DNA synthesis is impact and Alnico Magnets regulated by the magnetic field, which leading to its synthesis becoming faster, thus the cells in S phase increased, but the speculate lack of firm evidence. The paper reported frequency magnetic field can give rise to epithelial cell DNA double-strand breaks, speculated that the magnetic field affect the biochemical and enlarge the process, indirectly damage DNA, but the specific mechanism is not yet clear.. In order to explore the effect on DNA synthesis and DNA double-strand breaks by magnetic field, We chose a relatively simple uniform magnetic field, study the affect on DNA synthesis and DNA double-strand breaks by such magnetic field, conclused that this impact related to magnetic field strength. In order to verify the conclusions, need to design a uniform magnetic field strength devices, and can control the temperature of the magnetic field area. this combination of knowledge, we related knowledge, and design the magnetic field devices
　　.The main task of S-phase cells is DNA replication. In the process of DNA replication rotation, with the advance copy fork, front-end DNA molecule will produce torque, in order to release the accumulated torque, the double-stranded DNA molecules which is the front fork will appear special forms of exercise so as to release torque. and ensure the normal DNA replication. DNA is the biological macromolecules,negatively chargedthe on lateral, when the copy process been in a magnetic field, that will be the role of Lorentz force, which leading to changes in speed of DNA synthesis and thus the entire DNA molecule replication process will be interference, cell cycle will also change. On the basis of the phenomenon observed by the biological effects of magnetic team,and combination of the specific characteristics of DNA replication,
　　This article theoretically discussed the affects on the uniform magnetic field on the DNA replication process,and found that uniform magnetic field will increase the speed of DNA synthesis, at the same time result in changes in the structure of DNA.At present, in order to in-depth study the mechanism of the affect on organisms by electromagnetic fields , the researchers often use relatively simple form of the magnetic field as outside interference magnetic fields, such as: http://www.999magnet.com/products/108-alnico-magnets static magnetic fields, alternating magnetic fields, pulse magnetic fields and high-frequency magnetic field. with the need, the researchers used are: permanent magnets,electromagnetic Helmholtz coils and solenoids as magnetic field devices. Permanent magnet can provide for a maximum intensity of the magnetic field around Tesla, Helmholtz coils and solenoids can provide alternating magnetic field or relatively uniform magnetic field, and solenoids can also be used to provide strength for the solenoid around 10 Tesla. Various magnetic field devices have a certain scope, this article from the perspective of physics, analyse the characteristics of the each device, with magnetic characteristics of each and magnetobiology research, we summed up a more practical magnetic field devices, http://www.999magnet.com/products/108-alnico-magnets According to the experiment requirements, design a practical magnetic field devices which can provide uniform magnetic fields, and take a solution which can control the temperature of the magnetic field of regional. Through computer simulation model,we find that the magnetic field in the device field is consistent with the expected results, through the actual model of temperature detection, confirmed the temperature control is practical. The uniform magnetic field devices is made up of power, solenoids, the water cycle, focusing on the solenoid and the water cycle temperature control device design.

Design and Realization of Control System for Nautical Electromotion-Rudder

　　Design and Realization of Control System for Nautical Electromotion-Rudder
　　This research was concentrated on designing and implement main rudder servo system of ship main/flapped rudder system. Adopted digital signal processor of TMS320F2812 as main controller and the permanent magnet synchronous motor(PMSM) as executor. The main content included designing of collectivity scheme、building PMSM’s simple model and researching of motor controlling method、4 designing of controller、designing of hardware circuit、designing of software procedure and experiment of jointing hardware and software.In Neodymium Magnets designing of collectivity scheme aspect, designed the whole system structure, adopted half-closed loop structure; and validated the correctness of choosing component, such as DSP、motor and IPM.In researching of motor controlling method aspect, according to vector control method made the PMSM math model simpler . Realized the space vector pulse width modulation based on input variable which is reference variable of two-phase static coordinate, and optimized it for less switch waste.In designing of controller aspect, adopted three closed loops structure, For the used as practice project, PI controlling way was used in inside circuit loop and speed loop, and variable structure controlling way was used in outside position loop. Emulation proved that the controller was good on current following、speed rapid and position nicety.In hardware designing aspect, designing concerned system main circuit、power circuit、controller circuit、interface circuit and dependability. Introduced the reasons and matter need pay attention, explained the http://www.999magnet.com/products/110-sintered-neodymium-magnets way of some important components chosen and their parameter. Realized the hardware by PCB.In software designing aspect, designed the main procedure and several interrupt subprograms, and gave the procedure sketch maps. The key subprograms such as rotor position initialization、speed measuring and position measureing were given detailed designing and implementing means. At last, did joint experiment of hardware and software, made the system running on the different conditions and tested the current、speed and position’s experiment results. The results prove that the designing system has good capabilities, and can achieve the anticipating aim.

　　The Design and Simulation Research of AC PMSM Servo System
　　This thesis particularly described the design of full digital AC servo system based on the PMSM(Permanent Magnet Synchronous Motor). With discussing the difference among several control strategies and analyzing mathematical model of PMSM, the id = 0 vector control for the SPMSM had been chosen to be the strategy of this servo system. The theory of SVPWM and the ways of locating the PMSM’s rotor pole had been presented in this thesis. The establishing of the three loops servo system of PMSM which is based on the id = 0 vector control by use of the Saber Designer had also been introduced.The design of three loops servo system’s controllers was the key point of this thesis. With analyzing the function requirement of three loops servo system, as for the current loop, the author adopted PI controller to ensure the performance of speediness and anti-disturbance;
　　Considering the performance criterion of the velocity controller such as overshoot, regulating time, disturbance and precision, and the advantages and disadvantages of several kinds of controllers;As for the position loop,we chose the proportion and feedforward controller to satisfy the performance criterion of the locating precision , tracking precision and the range of overshoot. Then by the use of Saber Designer, we proved the arithmetic of controllers that we finally determined to be right.On the basis of the analysis of the theory and result of simulation, we designed the hardware and software of the full digital AC servo system. The hardware of the servo system could be divided into two parts, the first was the control circuit part and the other was the power circuit part. And the design of the galvanometry and photoelectric-encoder was the key point,While the content of software described the key design method and the flowchart of the software designing. The last paragraph of this thesis referred to the experiments of three loops of the servo system, the results of the experiment proved that the performance of the control system was satisfying, and validated the strategy that we had designed.

Finite Element Analysis and Research on PM Motor Rotor Mechanical Design

　　Finite Element Analysis and Research on PM Motor Rotor Mechanical Design
　　The mechanical calculation and design on PM motor is always performed after electrical design .In order to match the electrical design, the size is usually designed so weak that the motor can not work normally .This paper concerns a mechanical invalidation of rotor on a motor .Through the 2-D finite element analysis on the rotor of the PM motor, Ball Neodymium Magnets some valuable results are gained.Five parts of this thesis are included as follows:At first, the theories of elasto-plasticity including mises yielding criterion, loading condition are presented as the basic theories.Second, the application of FEM are stated, including the basic method and the basic analysis process as well as the variation principle and Ritz method. Some formulas of; numerical analysis on elasto-plasticity mechanics are also deduced here.Third, some of the basic concepts and principles relating to contact finite element analysis are presented. On the basis of the known research on the intensity of the rotor, the nonlinear contact finite element analysis is suggested. The analysis process and basic theory on FEA are importantly stated as the guideline to make the solve of analysis more approximately to the real case.Forth, the http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php static analysis finite element models of a rotor including nonlinear contact are set up by understanding the underlying theory. Based on the FEA software ANSYS, the rotor’s stress and radial shift are acquired by 2-D coupled-filed FEM, with the consideration about coupled electromagnetic-mechanical problems. The improvement of rotor is also obtained from the analysis.At last, an experiment is designed to proof the FEA to be reliable.

The Design of AC Servo System and Its Monitor Software for the PMSM

　　The Design of AC Servo System and Its Monitor Software for the PMSM
　　With the development of power electronics and the technology of the motor manufactory, and the progress of theory of AC speed regulation and novel control strategy, the control system for PMSM has been widely used in several high- technical fields such as the electromechanical integration, robot, the automotive electronics and etc. The Ball Neodymium Magnets fully digital synchronous servo system that based on the technology of digital signal processing and high-performance control strategy, and make the PMSM as its executive motor, must be the tide of the servo system progress.This thesis has summarized the research situation and the tide of the development of the servo system in home and abroad.
　　Based on the design of the servo control system and its monitor software, the author has finished the works in this thesis as follow:First of all, introduced the notion and research status of the AC synchronous servo system in home and abroad; Then created the mathematical models of PMSM, described the vector control strategy, and determined the rotor magnet field oriented control strategy to be the final control strategy; Respectively introduced the control circuit and the power circuit of the servo system’s hardware. TMS320F2407A and MAX3128 were chosen http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php as the core of the control part, and the IPM (Intelligent Power Module) produced by MITSUBISHI was chosen as the innermost device of the power part; Thirdly, described the design of the servo system’s software in CCS2.0 (a programming platform offered by Texas Instrument) based on the technology of mixed programming, and discussed the detail of mixed programming on DSPs; Finally, for the convenience of the operator’s modification of the parameters, the monitoring and analysis of the sampled data, and satisfying the demand of to be visible, we designed the monitor software of the servo system by the use of Visual C++6.0.

Research of HCB Novel Motor Operating Mechanism

　　Research of HCB Novel Motor Operating Mechanism
　　For high voltage circuit breaker, operation mechanism should fast response and have high opening and closing speed. Hydraulic mechanism and spring mechanism are used widely nowadays. But they are making up of complicated mechanism assembly, and parts is more, actuating mechanism complex, manufacturing technique requires higher, and moving procedure is uncontrolled. So, it is necessary for researching an operation mechanism with fewer parts, more simple construction, and moving procedure is controlled.In this paper, we analyzed the demand of novel motor operation mechanism and its driving motor for circuit breaker, compared the characteristics neodymium prices of different kinds of motors. The permanent magnetic brush-less motor is chosen as the driving motor of motor operation mechanism. According to the defects of existing operation mechanism, motor operation mechanism is designed for 40.5kV vacuum circuit breaker with which the model number is TD-40.5/1600-31.5. The relationships between the motor striking angle and contact stroke, the equivalent rotary inertia and counterforce characteristics during the motion of motor are gained after calculating the moving characteristics of motor operation mechanism. The preinstall stroke course of contactor is given according to the parameter of arc-chute. Calculate the dynamic characteristics of the circuit breaker as moving contactor moving with preinstall stroke course, the design standards of electric motor is given according to it.
　　The permanent magnetic brushless DC motor is improved reference the properties of short moving stroke, big counterforce and higher speed requirement and so on of CB operation mechanism, then the permanent magnetic brushless DC motor with finity rotate angle is designed. Not only the features of quicker responding and bigger torque of rare-earth http://www.999magnet.com/products/142-neodymium-prices permanent magnetic brushless DC motor are reserved, and the defect of commutating spark and structure complex of DC motor is overcomed due to the electronic commutation, meanwhile, the features of no excitation loss and high efficiency of permanent magnetic motor are acquired and the motor structure is no commutation, more simple and control easier. The designed motor are simulated by using finite element software. The results indicate that the design is reasonable and performance is reliable. And data processing method are adapted to analysis dynamic characteristics of motor operation mechanism.The analyzed results indicate that the motor operation mechanism are of high response, short opening and closing time, quick speed of opening and closing. It is not only fit for the capability requirement of circuit breaker, but also can improve the opening and closing capabilities of circuit breaker. The moving course can be controlled easily, and the intelligentize operation are realzed. The structure of novel motor operation mechanism is much simple. It is significance to improve the intelligence level by means of adding the servo control of motor to overcome the uncontrolled property.

Optimization and Simulation on Control System for Variable Frequency Air-conditioner Compressor

　　Optimization and Simulation on Control System for Variable Frequency Air-conditioner Compressor
　　With the greatest economic boom ever, energy consumption and environment protection have been the urgent issues for China. Being one of the main electricity consumers in family life, traditional air-conditioner has its drawbacks on energy saving and noise reduction. With the superiority on these drawbacks, the Variable Frequency Air-conditioner which always works at low-frequency is a development trend of air-conditioner.In recent years, AC Induction Motors have been widely used in the driver of air-conditioner, while Permanent Magnet Synchronous Cast Alnico Magnet Motors (PMSM) and Brushless DC Motors (BLDCM) are becoming more and more popular due to their high performance. Comparing to BLDCM, PMSM has its superiority on both of torque ripple and speed fluctuation. However, since PMSM has problems of low-speed torque ripple with vibration and noise, as well as hall sensors which cost a lot and is hard to maintain, Variable Frequency air-conditioner still faces the limitation of high cost and immature technology. Therefore, we propose an optimal control algorithm to suppress the low-speed torque ripple of PMSM, combining with the sensorless control solution.Starting from the model of PMSM, this paper firstly proposes an optimal control algorithm based http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php on stator current to suppress the torque ripple in low speed region. Then, the sensorless drive system is realized by sensorless control algorithm. Besides, after analyzing the model and high order harmonics of BLDCM, the optimal control algorithm is extended to the torque ripple minimization of BLDCM. Simulation results on MATLAB have shown the effectiveness and practical availability of the proposed method.

抽油机用BLDCM控制及解析设计法研究

　　抽油机用BLDCM控制及解析设计法研究
　　The oil driller requires the driving motor to have high start torque and can be speed-adjusted easily. Due to the negative torque of the driller load, the BLDCM will rotate too high, which reduces the system’ s life.Based on the above question, single stroke motor-stopping method is proposed. By the self-study function of ANN LMS method, the motor-stopping point can be regulated to the best point, and the speed rebound will be the least. Simulation is made which confirms this method. Meanwhile, combined with single stroke motor-stopping method, the neodymium prices software and hardware of BLDCM control system is completed, but the feasibility of the single stroke motor-stopping method is not verified. The experiment result is satisfying.Normally the analysis and calculation of BLDCM is based on the ideal air gap magnetic field. The actual magnetic field is different from the ideal value, so the analysis and calculation result precision is not good. In order to analysis and calculate the BLDCM properly, the veracity of air gap magnetic field must be assured.
　　For the surface mounted BLDCM, this paper imports the air gap magnetic field analytical calculation model as the foundation of this kind of motor’ s analysis and calculation. Furthermore, these work is completed based on the analytical calculation method:1.The BLDCM electromagnetism calculation method based on air gap magnetic field analytical calculation is proposed. The design calculation precision is greatly improved to this kind of motor. And the experience coefficents are not needed, which is very important to this kind of motor’ s design and optimization. http://www.999magnet.com/products/142-neodymium-prices   2. The BLDCM field route coupling model is proposed, which provides reliable and accurate calculation method to calculation of motor characteristic parameters.3.The analytical calculation method of motor coil inductance parameter is provided. The inductance parameter can be calculated properly, which can provide reliable parameter to the field route coupling model.4. According to the field route coupling model, the DC bus current and the phase coil current are analyzed. The result shows that the average value of the two current are not the same, which must be considered in the motor design.

Research and Application of the Novel Control Strategy in AC Servo System

　　Research and Application of the Novel Control Strategy in AC Servo System
　　Because of several advantages, e.g. compact structure, high air-gap flux density and high torque capability, the permanent magnet synchronous motors (PMSM) are broadly applied in high precision position servo system. The control performance is influenced by factors as the plant parameter variations, the external load disturbances, and the uncertainties or nonlinear dynamics.Based on the comprehensively deep research on the PMSM mathematic model, a novel control strategy, the active disturbance rejection controller (ADRC), is proposed to achieve high performance PMSM drive, which has great ability of adaptation and better performance against disturbance.
　　The active disturbance rejection strategy is independence of plant models. ADRC is composed of three parts: tracking differentiator extended state observer and nonlinear state error feed back control law. By using the extended state Alnico Magnets observer, the AC position servo system has stronger robustness, which can overcome nonlinearity and coupling of the parameters of PMSM. Also, it can surmount parameters excursion caused by temperature change. To compensate the disturbance caused by friction in the system and verify the high performance of ADRC, the principle of friction is researched and the Stribeck friction model is built in the thesis, and the model is used in the AC servo position system. A simulation model of AC position servo system is erected by MATLAB. Simulation results demonstrate ADRC has a fast responding speed, a high stable precision and robustness than the conventional PID controller.Control method of PMSM servo system without position and speed sensor is also presented in this paper on the basis of the active disturbance http://www.999magnet.com/products/108-alnico-magnets
 rejection concept. With the help of compensation by ADRC, the external load disturbances and the friction disturbances of the servo system on speed estimation are eliminated. The approach is implemented on the basis of MATLAB, and the performance of rotor position and speed tracking and the performance of robustness is verified by simulation results. Based on the work above, a AC position system including the DSP TMS320LF2407A is designed as the central department, and the monitor control system based on CAN bus is also developed.

Research on Application of State Observer in Servo Control System

　　Research on Application of State Observer in Servo Control System
　　With the rapid development of power electronic technology、micro-compter technology、rare-earth permanent magnetic materials and the control theory, permanent-magnet synchronous motor(PMSM) has been widely used in motion control system with low or medium capacity. However,the permanent-magnet synchronous servo system is easily Block neodymium magnet influenced by factors such as the changing parameters of the electrical machine, the disturbing effect from outside load and the sensor noise ect. People have to do some research on the advanced control strategies and control methods in order to acquire the high performance and low cost permanent-magnet synchronous servo system which has strong adaptability and the capacity of anti-disturbing. This paper is mainly centered about the research on high performance and low cost permanent-magnet synchronous servo system.
　　The mathematics model of the permanent-magnet synchronous motor (PMSM)in d-q reference frame is established , and the PMSM vector control strategy is analyzed and then the control method rotor field-orientation vector control of i d=0 is chosen. According to the automatic control theory, the components and the mathematics models of the permanent-magnet synchronous servo system are analyzed in detail, in accordance with the engineering design method of automatic control system adjustor ,the current loop and the velocity loop are designed. In order to meet the http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php needs of rapid dynamic respond and at the same time ,make the system has the strong ability of anti-disturbing and restraining the sensor noise, The state observer is introduced in the control system, the current loop state observer and the velocity loop state observer are set up respectively, by these means, the parameters such as the feedback current,position, velocity and the load torque can be estimated in advance. Based on these, The simulink design on the whole system under the simulink circumstance is proposed in this paper. In the simulink design, the relationship between the system’s dynamic performance and the parameters of the system adjustor and state observer are discussed detailedly; further more, how the adjustor and state observer’s parameters can influence the sensor noise are analyzed; the solving methods in system control are presented.The performance comparisons between the systems using digital filter and the state observer are given. The experimental results show that the system using the state observer has more excellent quality in tracking and anti-disturbing.

基于飞轮储能系统的永磁同步电机控制系统设计

　　基于飞轮储能系统的永磁同步电机控制系统设计
　　Embedded System is an integrated complex digital system. In the applications of embedded systems, the common way to deal with image acquisition and processing is to use embedded processor (ARM, PowerPC, etc.) and digital signal processor (DSP) or application-specific integrated circuit (ASIC) to build the systems. SOPC (System On Programmable Chip) means on-chip system that can be programmed, or a large-scale FPGA-based single-chip system. The technology of design of SOPC is products of the modern computer-aided design technology, EDA technologies and large-scale integrated circuits’ developments. With the development of EDA technology, it is a trend that the programmable system on a chip become the control center of the data acquisition Ball Neodymium Magnets and processing system, particularly in the area of image acquisition and processing system. Because of the lower cost of FPGA, the parallel processing ability of hardware and the rich resources of IP core, the design can make use of its unique advantages of FPGA. The obvious advantage of SOPC based on the FPGA is that the design can be improved and upgrade without replacing chip; also the costs can be reduced and the reliability can be improved.The paper proposes a solution to image acquisition and processing using the FPGA. The system uses XC2VP30 , the Virtex series of chips of Xilinx company, which is embedded in the Microblaze soft processor IP core and peripheral hardware to construct the hareware of the system, and transplants uClinux operating system to construct software systems, and use hardware and software co-design approach during the development of the system.
　　The introduction of such systems architecture system that has a lot of advantages that because of FPGA the system has logic processing capability, such as the method of using the hardware logic to achieve the graphics acquisition and processing, has the advantage of achieving rapid image acquisition and JPEG compression, as well as making use of the the powerful uClinux operating system which can provides function of web server, file system and network transmission and so on.And the system can make use of the existing IP core systems for hardware design, such as Xilinx company’s IP Core of DDRRAM Controller, FLASH controller and the use of 8 bits soft core Picoblaze to design MT9V011 controller. On the other hand, during the design of the system the paper states the characteristics of the method of the hardware and software co-design, which is used in the development. http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php   The method of Hardware and software co-design has changed the disadvantage of the traditional design that repeats modification to the system. Through a comprehensive analysis of the function of the combination of hardware and software ,the new method make the development of hardware and software be more closely, and greatly enhance the efficiency of design, also make the system design more optimized than the traditional design method.The paper describes the entire system design in the aspects of hardware and software. As to the system architecture, hardware and software co-design method is used for system design, and hardware and software division. In terms of hardware the system is divided based on the function of modules, including design for image acquisition system IP core, image processing hardware IP core, and the LED display or PS2 controller IP core . In terms of software the paper introduces transplant of the uClinux, the driver module design and design for the upper-class software and so on to clarify the features and ideas of the software design for the whole system.

小型化MRI永磁系统的设计

　　小型化MRI永磁系统的设计
　　There are many projects of magnet design in the nuclear magnetic resonance. But if applied both small and lightweight, even large areas,good stability, we face a series of problems. These problems mainly rely on the calculation of electromagnetic fields. These questions were elaborated in the paper, and then optimized the analysis of the programme, to Cast Alnico Magnet identify the best solution. The uniform regional magnetic field established in the external side of magnet is a brand-new question which the magnet design faces. The feasibility of magnetic miniaturization design was explored by a counter mixed numerical algorithm. Numerical algorithm is one two steps of algorithms, including direct matrix inversion for counting and secondary planning. The details of this numerical algorithm ,which was used to find a more successful combination of magnetic pieces unilateral permanent magnetism magnetic structures ,were described in the paper. Software simulation models by Maxwell 3D/2D http://www.chinamagnets.biz/Alnico/Cast-Alnico-Magnet.php and measurements show that the structure can be better applied in establishment of magnetic field area in the external side of magnet. Thus we can lay the ground work for miniaturization unilateral homogeneous field of conventional magnetic resonance imaging system.

The Study of Electroless Plating of Ni-Cr-P/Ni-P Complex Coating on Nd-Fe-B Magnet

　　The Study of Electroless Plating of Ni-Cr-P/Ni-P Complex Coating on Nd-Fe-B Magnet
　　Nd-Fe-B magnet, which possesses excellent magnetic properties andwas discovered by Japan and the USA in 1983, is a new type of permanentmagnetic material. Since the discovery, its research and application hasbeen hot spots of the study of magnetic materials. However, its poorcorrosion resistance limits its application range.
　　To improve the corrosionresistances of Nd-Fe-B type magnets, lots of attempts have been done,such as: other alloy elements additions and surface coatings.Among all surface coatings, amorphous Ni-P coating, whichpossesses more excellent neodymium prices mechanical, magnetic and anti-corrosionperformance over the crystal materials, may be one of the best. However,along with the development of science and technology, Ni-P coating cannot continue to fulfill the daily elevated anticorrosion request of modernindustry on Nd-Fe-B magnet. By adding chromic salt into the platingsolution of Ni-P coating, Ni-Cr-P coating can be fabricated. The process issimple and convenient, the coating also show better corrosion resistancethan Ni-P coating. But Ni-Cr-P coating also has its downsides, like lowercompactness and higher porosity rate. To combine the advantages of theseto coatings, the electroless plating technics of Ni-Cr-P/Ni-P complex coating is studied in this paper.First, the perpendicular experiment is used to select the opticaltechnical parameters of both alkaline and acidic Ni-P http://www.999magnet.com/products/142-neodymium-prices electroless plating.Structure analysis and performance testing shows that the Ni-P coating hashigh compactness and low porosity rate. It also shows great corrosionresistance in alkaline medium, but not so well in acidic medium.Then the perpendicular experiment is used to select the opticaltechnical parameters of Ni-Cr-P electroless plating. The effects oftemperature, pH valve and chromic salt concentration on depositionvelocity and corrosion resistance are also discussed. Structure analyses andperformance testing shows that the Ni-Cr-P coating has amorphousstructure, high compactness and low porosity rate.Finally, the structure and performances of several different complexcoating are studied and tested, also compared to the Ni-P coating. Theresults show that, the complex coating prepared by Ni-Cr-P electrolessplating (15min) and Ni-P acidic electroless plating (45min) has amorphousstructure, simple process and better anticorrosion performance in bothalkaline and acidic medium. A logical solution of the anticorrosion ofNd-Fe-B magnet has been offered.

Research on Permanent-Magnet Synchronous Motor AC Servo System

　　Research on Permanent-Magnet Synchronous Motor AC Servo System
　　Permanent magnet synchronous motors (PMSM) have shown increasing popularity for high performance servo systems due to the recent developments of magnetic materials, power converters and digital signal processors. PMSM have the characters of high running efficiency, great power density, low inertia, high reliability, etc. It neodymium standard state does not need an external power supply to excite the rotor field and hence the field winding and slip rings are eliminated.This thesis sets up the mathematical model of the permanent magnet synchronous motor in SIMULINK. Current hysteresis band PWM, SPWM and space vector PWM have been analyzed. It sets up vector control model in SIMULINK. It realizes the control by two different ways, hysteresis and SPWM. The model works well when the giving torque changes.On the base of principle and simulation analysis, the thesis particularly presents the designing and realizing methods on the whole servo system’s hardware and software. The control scheme is implemented using a high speed DSP, TMS320LF2407A http://www.999magnet.com/products/112-neodymium-standard-state and a CPLD EPM3128ATC100-10. The software is implemented by assembly language. Furthermore the experiment results for the full-digital servo system presented. These waves and data indicate the speed servo systems which are designed in this thesis have satisfying dynamic and static performance.

Research and Application of the Direct Torque Control System Based on Permanent Magnet Synchronous Motor

　　Research and Application of the Direct Torque Control System Based on Permanent Magnet Synchronous Motor
　　Permanent Magnet Synchronous Motor(PMSM) drive by triphase sinusoidal current is research object in this thesis. This thesis further investigated the basic principle of controlling the method of direct torque of the PMSM. Based on evaluating the PMSM for organization and characteristic, its mathematics models in several coordinate were set up. The thesis analyzed the principle of PMSM DTC and proposed the PMSM DTC strategy.In the paper, an adaptive fuzzy controller is designed in order to improve the static and dynamic performances of permanent Alnico Magnets magnet synchronous motors (PMSM) under direct torque control (DTC) techniques. The fuzzy control and adaptive mechanism makes the whole control system more robust and adaptive. Some simplified and optimized algorithm is proposed in the paper by which the controller is realized easily and the real-time feature is better. By the theory analysis and simulation based on MatLab6.5/Simulink.The proposed strategy is proved to enable diminishing the torque ripple. Especially in low speed rang. In addition, both the precision of controlling and high dynamic performance was achieved.Based on the analysis of the http://www.999magnet.com/products/108-alnico-magnets principle of PMSM DTC, the thesis proposed a soft-start strategy for PMSM DTC system and set up the modules with MATLAB. The simulation and experiment results shows that the method can low the starter current effectively and make PMSM start smoothly.Based on the principle and structure of the direct torque control of PMSM, This thesis proposed two improved PMSM DTC systems and set up the modules of these systems with MATLAB/Simulink. Through the simulation of these improved system. The results were concordant with the theory analysis.

An Investigation on Voltage Regulation Device of Vehicle Permanent Magnet Generators

　　An Investigation on Voltage Regulation Device of Vehicle Permanent Magnet Generators
　　More and more electrical appliances were used in various vehicles at present, so higher quality was requested for Vehicle generators. Voltage was regulated with controlling exciting current in traditional Vehicle generators. A lot of energy was comsumed with exciting current at low speed for the great operation speed variation of vehicle generators. Neodymium Magnets Therefore the efficiency of generator was low. Because of no exciting winding, a permanent magnet generator has the properties of simple construction, long operation life and high efficiency. The output voltage of a permanent magnet generator was changed with variation of the load and speed.A voltage regulation method was pesented in the paper to improve the voltage output in a permanent magnet generator for the power source of vehivle appliances and battery. This voltage regulation system can control the http://www.999magnet.com/products/110-sintered-neodymium-magnets output characteristics according to the operaing state of the permanent magnet generator and battery, and so improve the system performance. A propotype was completed with above method and the experimental results shows that performance meets the demand.

Study on Electromagnetic Design and Control Strategy Simulation for Bearingless Permanent Magnet-type Synchronous Motor

　　Study on Electromagnetic Design and Control Strategy Simulation for Bearingless Permanent Magnet-type Synchronous Motor
　　A bearingless permanent magnet-type synchronous motor(BPMSM) is a novel motor, in which the levitation winding for levitation force is embedded in armature core. Its rotor can product both rotating torque and levitation force. The permanent magnet synchronous motor has the merits of high power, long life, high efficiency and small volume. Ball Neodymium Magnets With the advantage of bearingless, the BPMSM has expended the application field of high-speed motor in micromation and high power range. Its unique levitation mechanism and structural characteristics made it more economic and technology advantages than traditional motors in some high technology field, and it has widely application foreground.This dissertation is devoted to mathematics model establishment and electromagnetic design of the BMPSM, including proposing a feasible control strategy. The concrete content is as follow:Firstly, based on the fundamental principle of the bearingless and producing radial suspension forces in BPMSM, the levitation force mathematic model of BPMSM is deduced. Study on the influence factors and its influence laws of levitation force using finite element method(FEM). Make verification and correction of the levitation force model, which produce a accurate levitation force http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php mathematic model.Secondly, based on the levitation force modal and FEM analysis, the relationships between levitation force and permanent magnet thickness, air-gap length in a surface permanent magnet synchronous bearingless motor are found. A electromagnetic design method is proposed, which can complete the electromagnetic design considering both levitation force and torque requirement. The validity of this design is verifiede by FEM.Finally, based on the models of electromagnetic torque and levitation force, a i1 d =0 rotor field oriented torque control and a direct control for rotor eccentric displacement levitation force control strategy are applied. The control system is constructed using Matlab/Simulink toolbox. The operation performances are simulated. Simulation results have shown that this control strategy realizes direct control for rotor eccentric displacement.

The Design of an Intelligent Controller of Permanent Magnetic Actuator

　　The Design of an Intelligent Controller of Permanent Magnetic Actuator
　　As a popular component of middle-voltage breaker, the reliability of its actuator is very important. As a new kind of Actuator of circuit breaker, permanent magnetic actuator (PMA) has many advantages, such as less parts, higher reliability, no maintenance and so on. It provides hardware basement for enhancing stability of breakers and also can be used to Ball Neodymium Magnets realize intellectual control.First of all, a brief introduction of middle-voltage breaker’s actuator is given in this paper. According to the demands of vacuum breaker, the advantages of permanent magnetic actuator is discussed. With that the necessity and the urgency of a new kind of an intellectual actuator is emphasized.Then, according to the characteristic of permanent magnetic actuator, the structure and the operation principles of permanent magnetic actuator is discussed. To establish the theoretical foundation for realizing intellectual control, the magnetism field characteristic of bi-stable permanent magnetic actuator is analyzed. Then the frame of intelligent control system for the single coil permanent magnetic actuator is introduced.In the following parts, the intelligent control system is introduced in details in both hardware and software aspects. The hardware of the system is divided into six parts, such as the power source system, main chip MCU system, data collecting system, display system and the communicate system. http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php And the software is divided into four parts, such as the main part system, monitor and execute system, status disposing system, and communicate system.At last, we work out the intelligence control system using the single-chip microprocessor of STC89C516RD+ and other parts of unit, according to the single coil permanent magnetic actuator’s characteristic. Seeking for the simple and less cost controller. The device can realize the function of monitoring, protecting, controlling, and measuring. The device can control the operation of the circuit breaker intellectually, and also has the functions of over-current protection, diagnosis and warning for the failure of the operation system.

Implementation of Permanent Magnet Synchronous Motor Servo System Based on DSP

　　Implementation of Permanent Magnet Synchronous Motor Servo System Based on DSP
　　With the development of power electronics, computer technology, electromechanics, and control theory, permanent magnet synchronous motor (PMSM) has been widely applied in servo system of low and medium capacity, and it is gradually taking the place of DC motor and stepper motor. The thesis focuses on the design of the system of PMSM Block neodymium magnet servo system based on the advanced Digital Signal Processor (DSP) chip-TMS320F2812, and has done some theoretic researches as well as experimental research are presented in detail First, this dissertation illustrates the mathematic model of PMSM.According to the transformations of motor reference frame, the torque control can be separated independently into the current control of direct axis and quadrature axis. By considering the practical need, zero direct axis current control mode is chosen. Then the implementation of vector control on DSP platform is demonstrated based on the constructed model. Space vector PWM is chosen among all kinds of inverting technology whose theories and realization is also presented.After the modeling analysis and implementation scheme, a digital permanent magnet AC servo http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php system is developed step by step. And every detailed step of both hardware and software design is depicted in this dissertation.Additionally, this paper devises a novel method for the rotor initial position detection, in which, depending on a particular algorithm, the rotor position can be found when the motor stops moving.The experiments are carried out finally, whose results show that the designed servo system meets the demand of required performance and paves the way for future research.

The Design and Optimization of Permanent Magnet Structure Producing a Slice of Homogeneous Magnetic Field

　　The Design and Optimization of Permanent Magnet Structure Producing a Slice of Homogeneous Magnetic Field
　　The permanent magnet Magnetic Resonance Imaging (MRI) device is a kind of advanced medical diagnostic device, which can obtain the images of interior tissue of human body. Due to its good openness and lower maintenance fee, the completely open permanent magnet MRI is attracting more and more people’s attention. The main magnet is one of the main parts of MRI. The permanent magnet structure involved in this paper, which can produce a slice of homogeneous magnetic field, is just about to use as the main magnet of MRI. Aimed at how to Block Ceramic Magnets obtain a better main magnet structure, this paper has done the following research work:Firstly, on the basis of introducing the theory of Response Surface Methodology (RSM), the advantages and disadvantages of several kinds of interpolation basis functions used to construct response surface model in present has been summarized, and how to assume the shape parameter a value when using radial basis function as the interpolation function has been discussed too. Moreover RSM and the improved Genetic Algorithm (GA) have been combined together, and a new kind of optimization method which can solve large magnetic field inverse problems has been proposed, and was fulfilled by programming.Secondly, the advantages and disadvantages of classical multi-objective optimization method has been analyzed, the multi-objective optimization method based on GA has been detailedly introduced. Furthermore the typical non-Pareto optimization method--vector evaluated GA, the optimization method based on Pareto—Non-dominated Sorting GA (NSGA) and the fast elitist Non-dominated Sorting GA (NSGA-Ⅱ) have been mainly discussed. Moreover, the RSM was introduced into the NSGA-Ⅱ,
　　which makes the multi-objective optimization of large magnetic field inverse problem more efficient and timesaving. At the same time aimed at the http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php characteristic of the populations of the NSGA-Ⅱnot disperse enough, the original crossover operator of the NSGA-Ⅱhas been improved. Numerical experiment results show the improved method is very efficient. At last, a kind of permanent magnet structure which can produce a slice of homogeneous magnetic field has been presented, and a process of single-objective optimization has been fulfilled. After optimization the results have been analyzed by electromagnetic field analytical tools, and it has been proved that the magnetic field flux density, the homogeneity of each layer and the gradient between each layer could achieve the design requirements. This makes the model can use as a main magnet of MRI. Furthermore, a multi-objective optimization process of the permanent magnet structure using the proposed method has been completed, and the results can satisfy different design requirements. And a 3D model based on real model has been created by ANSOFT, comparison between f’mite element analytical results and accurate experimental results show the analytical tool is valid.

Appliance and Study of Fuzzy Control Strategy on the Direct Torque Control of Permanent Magnet Synchronous Motor

　　Appliance and Study of Fuzzy Control Strategy on the Direct Torque Control of Permanent Magnet Synchronous Motor
　　Along with the development of electrical machine design, manufacture technology and electric power electron technology, many technicians pay much more attention to the PMSM, which has many ideal performances such as simple structure, high efficiency, low rotor consumption, simpler control system than asynchronous motor. Its general design and control mode has been improving by the researchers, who engage in the study of electrical machine and its drive system, Block Ceramic Magnets correlative productions have been applied to the industry.DTC is the control mode of perfect dynamic and static performance, the basic idea is to control the stator flux linkage and the torque directly. Unlike vector control, the DTC does not require any current regulator, coordinate transformation. Orientation is achieved by stator flux linkage, not rotor flux linkage, which can avoid uncertain parameters which affect the system performance.This article reviews the developing history of the direct torque control technology, expatiates the direct torque control principle, set up the mathematics model of the permanent magnet synchronous motor systematically. The theory of fuzzy control is applied to the direct torque control system for synchronous permanent magnet motor.The modeling http://www.chinamagnets.biz/Ceramic/Block-Ceramic-Magnets.php and simulation of the direct torque control system for synchronous permanent magnet motor is carried on by MATLAB/SIMULINK. The results show that the feasibility of the direct torque control is fine, control structure is simple, dynamic response performance is ideal. The fuzzy DTC strategy, which is designed base on the characteristic of the PMSM, is able to achieve more superior operation performance than that of the conventional DTC. Torque ripple is restrained obviously. The system control performance is improved.

Study on Working Characteristics of Permanent Magnet Couplings

　　Study on Working Characteristics of Permanent Magnet Couplings
　　Generally speaking, permanent magnet couplings are composed of insidemagnet rotor, outside magnet rotor and isolative sleeve. The inside magnet rotor isconnected with follower,while the outside magnet rotor is connected with driver.On one hand, permanent magnet couplings have the function of cushion andabsorption of shock as well as flexible coupling,on the other hand, the most majorcharacteristic of permanent magnet couplings is that inside magnet rotor andisolative sleeve are isolated from others completely,besides this,under the conditionof no mechanical Tile magnets contact,the driver transfers motion and dynamic force to thefollower by means of magnetic force,in consequence,dynamic seal of permanentmagnet couplings becomes static seal. Therefore, permanent magnet couplings areapplied widely to the fields which have especial requirement of seal,such as fieldsof petroleum,chemical engineering, vacuum, low temperature, pharmacy, food,aviation and so on. According to the arrangement of magnet rotors, permanentmagnet couplings include sleeve type and disk type. In this article, the workingcharacteristics of sleeve-type Permanent Magnet Couplings which have eightmagnetic poles are studied.
　　This article consists of six parts shown as followed:1) Introduction This part introduces classification and working mechanics of permanentmagnet couplings simplely and research contents of this article.2) The analysis of air gap magnetic field of the permanent magnet couplings In this part, mathematics model of air gap magnetic field of the permanentmagnet couplings based on the theory of equivalent magnetic monopoles isestablished,and influences of main structural parameters on air gap magnetic fieldare analyzed.3) The analysis of magnetic torque of the permanent magnetcouplingsIn this part, mathematics model of magnetic torque of the permanent magnetcouplings based on the theory of equivalent magnetic monopoles is established,andinfluences of main structural parameters http://www.chinamagnets.biz/Neodymium/Tile-magnets.php on magnetic torque are analyzed.4) The analysis of eddy current loss in isolative sleeve,andmagnetic torque arose by eddy currentFirst of all, mathematics model of the eddy loss in isolative sleeve based onMaxwell equations and the mathematics model of air gap magnetic field isestablished,and influences of the relative rotation angle between magneticrotors,the rotational speed of magnetic rotors and the thickness of isolative sleeveon eddy current loss in isolative sleeve are analyzed. Then,the mathematics modelof magnetic torque arose by eddy current is established,and influences of therelative rotation angle between magnetic rotors,the rotational speed of magneticrotors and the thickness of isolative sleeve on magnetic torque arose by eddycurrent is analyzed.5) Module for analysis of magnetic field of the permanent magnetcouplings based on ANSYSFirstly,this part introduces user interface design language(UIDL) for graphicaluser interface(GUI) in ANSYS,and establishes module for analysis of magneticfield of the permanent magnet couplings with eight magnetic poles. In the end,thefinite element result obtained from an example is compared with the analyticalresult obtained from the mathematics model of air gap magnetic field of thepermanent magnet couplings.6) Conclusions and prospectsIn this part,conclusions of this article and prospects of the study in the futureare given.

Study and Design of Direct-driven Permanent Magnet Synchronous Wind-Energy Generation Control System

　　Study and Design of Direct-driven Permanent Magnet Synchronous Wind-Energy Generation Control System
　　With the aggravation of the energy crisis and the worsening of environment, the development and utilization of renewable energy are concerned by many countries around the world. As a way to use the renewable and clean energy, the wind-energy generation is developed rapidly. Comparing with doubly-fed AC excited wind-energy generation system, the direct-driven permanent magnet synchronous wind-energy generation system has features of simpler structure, higher Block neodymium magnet generation efficiency and higher operation reliability. The control of the direct-driven permanent magnet synchronous wind-energy generation system includes the control of both the generator-side converter and the grid-side converter. The output active power of the generator, the fluctuation of the torque and the wind-energy utilization efficiency are influenced by the control strategy of the generator-side converter. On the other hand, the active power transmission and the reactive power regulation are influenced by the control strategy of the grid-side converter. So, it is the key that an appropriate control strategy should be adopted to improve system performance.
　　The direct-driven permanent magnet synchronous generation system with the back-to-back PWM converter used as the grid-connected main circuit is studied in this thesis. Firstly, the mathematical model of the permanent magnet synchronous machine and coordinate transformation is analyzed, and the control strategy of the generator-side converter based on the vector control is studied. The maximum wind-energy tracking control strategy with the optimal reference power is studied from the characteristics of the wind turbine. The optimal setting value of the output active http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php power is calculated according to the generator rotation speed and the maximum wind-energy tracking control is realized by closed-loop regulation. Secondly, the control theory of the grid-side converter is analyzed and the mathematical model is built, and the control strategy of the grid-side converter is studied. The output active power of generator is transmitted to the grid by stably controlling DC-link voltage. The reactive power of the grid-side converter is regulated by controlling the reactive current of the grid-side converter. Lastly, the hardware of the direct-driven permanent magnet synchronous generation system is designed by using high speed digital signal processor TMS320F2812 and intelligent power module (IPM) and the software is accomplished according to the control model. The good performance of the generation system and the control strategy are validated through experimental research. The maximum wind-energy tracking control, the independent control of grid-connected active power and reactive power, and variable speed constant frequency (VSCF) generation are realized.

Research on a Radially Magnetized Permanent-Magnet Linear Generator Used for Hybrid Electric Vehicles

　Research on a Radially Magnetized Permanent-Magnet Linear Generator Used for Hybrid Electric Vehicles 　　The permanent-magnet linear generator in this thesis will be used in a series hybrid electric vehicle schemes as an auxiliary power generating unit(APU),which is connected with a free-piston combustion engine. This research is very popular because of the light Ball Neodymium Magnets weight, compact configuration, less energy loss and higher efficiency of the new system. Some research has been carried out on the permanent-magnet linear generator.Firstly, after introducing the configuration and the theory of the permanent-magnet linear generator, based on the finite element method (FEM), a FEM model of the permanent-magnet linear generator is established.Then, the generator is optimized from three aspects. The first aspect is the material selection used for the stator core. Iron loss is a big part of the machine loss and has a great act on the efficiency. So a good choice is needed. The second aspect is the arrangement of the magnets. It can decide whether the magnetic density distribution in the stator and translator iron is even. The last one is the dimension of the generator. It also http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php has a great act on the performance of the generator.The cogging force appears in all linear machines and is a big drawback of linear generator. After explain how to calculate the cogging force, the thesis analyzes some methods how to reduce the cogging force and the force ripple, such as the optimization of the pole embrace, the width of the side magnets and the width of the teeth.At last, the thesis does some research on the two different ways of the stator lamination, i.e., radial lamination and axial lamination. The different manufactures and the equivalent magnetic circuits are introduced, and the FEM models are established. And then the performance is calculated and compared.