Dissertations / Theses on the topic 'Permanent magnet research area'
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1
Camacho, Silva Leandro. "Modeling and Design of the Electric Drivetrain for the 2013 Research Concept Vehicle." Thesis, KTH, Elektrisk energiomvandling, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-133353.
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The research for electric vehicles has been growing during last years and the development of electric drive trains can be considered a main challenge. This thesis presents the electric drive train of the research concept vehicle (RCV) 2013, with particular focus on electric machines, motor controllers, and the communication system. In the first part of this thesis, the electric drive train configuration and components are described. In-wheel motors are proposed which is a permanent magnet synchronous machine (PMSM). This technology allows the use of autonomous corner modules (ACM) increasing the quality and safety of the system. Each of the four in-wheel motors has a controller enabling the use of torque or speed control mode. Furthermore, a dSPACE unit provides the total control of the system by CAN bus. Additionally, the dSPACE ControlDesk interface used to control the drive system is presented. In the second part, the heat sink of the AC Drive is investigated by measurements and analytical calculations. Furthermore, the motor temperature at different loads is also presented and discussed. Finally, the efficiency of an in-wheel motor (PRA 230) is studied. Also the efficiency of the motor controller is estimated and discussed.
2
Gaeta, Alberto. "Fault Tolerant Sensorless Permanent Magnet Synchronous Motor Drives." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/996.
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High cost and complexity of fault tolerant motor drives has relegated them to mission critical, no-compromise applications.
Heeding to this target application, past research efforts have been mainly focused on developing highly redundant, multiphase fault-tolerant solutions able to assure a very high fault tolerance level.
However, many other applications would benefit from the availability of solutions ensuring an acceptable level of fault tolerance.
The present work shows that, if tolerance is limited to few common faults and a reasonable performance penalty after a fault is accepted, a three-phase, voltage source inverter-fed, sensorless motor drive can be made fault tolerant by acting mainly on the control strategy, thus keeping to a minimum the required hardware modifications and additions.
After an initial classification of the possible faults which may affect three-phase VSI-fed drives, a fault detection and identification technique for converter faults is analyzed, able to ensure reduced response times. Therefore, modifications to a sensorless rotor position estimation technique are proposed in order to make a sensorless drive as fault tolerant as their sensored counterparts. Succesively, considering a PMSM motor with star center accessibility, two-phase sensorless operation is extensively studied and a new model is introduced maintaining the same control performance of a standard qd reference frame model. The new model is used for vector control of the machine either in sensored and sensorless conditions to confirm that advanced control of two-phase sensorless operation is the only post-fault strategy allowing the elimination of any redundant hardware.
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Pappu, Gita. "Design of a permanent magnet motor and a drive for cranking purposes." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43296.
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The development of Magnaquench in 1985 by the Delco-Remy laboratories, increased the research of applications of permanent magnets for use in automobiles. However the application of permanent magnet machines for cranking purposes has not been investigated much.
Difficult operating conditions, like, a maximum current density of 35A/mm², and the ability to withstand demagnetizing armature currents up to 250% of the stall current require a new design approach to be developed.
Commutation in the permanent magnet machine is obtained by a three phase full wave inverter. The machine - inverter model was simulated by a standard method (SPICE), and an second analytical method we developed.
A permanent magnet brushless motor and a drive for cranking purposes is designed and simulated as a part of this thesis.Master of Science
4
Gangla, Vineeta. "Analytical methods for electromechanical forces and torque computation in brushless permanent magnet machines." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-12052009-020038/.
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Bedford, Adam. "Strength in flexibility : research into innovative flexible bearing designs for wave convertor permanent magnet generators." Thesis, Lancaster University, 2011. http://clok.uclan.ac.uk/4192/.
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Originally this research was to investigate the use of hydrostatic bearings in large linear machines, such as linear generators, and determine their viability in a power generation context. It quickly became clear that it was possible to make hydro-static bearings viable, however the methods employed to do so gave rise to new possibilities which altered the scope of the research. The overall aim of the research has become to look at flexible construction, using modular generation units, as a means of creating more reliable and cost effective generators. The methods employed to do this involved modularising the generator's structure. Each module then acts as a generator in its own right transferring its power to the parent machine. The potential for each module design was assessed based on its losses, due to the bearings, and its economic potential, such as how it impacted the operation and maintenance costs or transport costs and consideration of how each design affected the power density of the parent machine. The basic structural analysis showed that, of the arrangements tried, there was a distinct advantage to restricting the number of bearings because it reduces energy losses. This is particularly true of designs that take advantage of the MMA concepts. The magnitude of the forces within the generators, during operation, lead to the creation 2-stage bearing and MMA concepts. The key reasons for them being to reducing dynamic forces within the generator and increase tolerance to design flaws and damage. Reducing the dynamic forces reduces losses in all types of bearings improving overall efficiency. Not all the concepts present in this document show commercial promise, however from the basic principles used to understand their working, there are some whose potential is clear. In general the modules have reduced the weight necessary to operate a successful generator and reduced the bearing losses no matter the type of bearing being used. Predicted force reductions mean that less strength critical and more cost effective materials can be used in the machines construction. Given that the original scope of the research was to assess a single type of bearing it has come a long way to incorporate construction methods that will reduce operation and transport costs, as well as being more efficient on some of the construction materials. The final module designs show great promise to increase the power density of generators whilst making them easy to maintain. Although hydrostatic bearings provide excellent lubrication the basic analysis performed herein shows that their energy consumption exceeds the energy loss of normal roller bearings reducing overall generator efficiency. The modular constructions presented may not provide a great jump in efficiency over previous designs however they do show a way to simplify operation and maintenance costs improving overall commercial viability. All 3D/CAD models contained herein were created by the author for this work unless otherwise stated/referenced.
6
Duffy, Michael James. "Small wind turbines mounted to existing structures." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34765.
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Small wind turbines, and especially urban-mounted turbines which require no dedicated pole, have garnered great public enthusiasm in recent years. This enthusiasm has fueled widespread growth among energy conservationists, and estimates predict that the power produced nationally by small wind will increase thirty-fold by 2013. Unfortunately, most of the wind resources currently available have been designed for larger, rural-mounted turbines; thus, they are not well suited for this nascent market. A consequence of this is that many potential urban small wind turbine owners over-predict their local wind resource, which is both costly and inefficient. According to a recent study published by Encraft Ltd., small wind turbines mounted to buildings far underperformed their rural pole mounted counterparts.
As a proposed solution to this problem, this project introduces the concept of a Web-based Wind Assessment System (WWAS). This system combines all the necessary resources for potential urban small wind turbine customers into a single web-based tool. The system also presents the concept of a modular wind measurement system, which couples with the WWAS to provide real-time wind data measurements. The benefits of the system include its ease of use, flexibility of installation, data accessibility from any web browser, and expert advice. The WWAS prevents potential clients from investing in a system that may not be viable for their location.
In addition, a small wind turbine is designed in this project, which has a unique modular mounting system, allowing the same baseline wind turbine to attach to various structures using interchangeable mounting hardware. This includes such accessible urban structures as street lights, building corners, flag poles, and building walls, among others.
This design also utilizes concepts that address some of the challenges associated with mounting small wind turbines to existing urban structures. These concepts include: swept tip blades and lower RPM to reduce noise; vibration suppression using rubber shims; a netted duct to protect wildlife; and a direct-drive permanent magnet generator to ensure low starting torque.
Finally, the cost of this system is calculated using off-the-shelf components, which minimize testing and certification expense. This small wind turbine system is designed to be grid-connected, has a 6 foot diameter rotor, and is rated at 1 kW. This design features a unique modular interchangeable mounting system. The cost for this complete system is estimated to be $2,050. If a users' site has an average wind speed of 14 mph (6.5 m/s), this system will generate a return on investment in 8.5 years, leaving over 10 years of profit. The profit for this system, at this sample average wind speed, yields over $4,000 during its 20-year design life, which is a two-fold return on investment.
This project has implications for various stakeholders in the small wind turbine market, including designers, engineers, manufacturers, and potential customers. Equally important is its potential role in guiding our future national--even global--energy agenda.
7
Silva, Leandro Camacho. "Modeling and Design of the Electric Drivetrain for the 2013 Research Concept Vehicle." Master's thesis, 2013. http://hdl.handle.net/10316/40436.
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Albino, Martin, Andrea Caneschi, Claudio Sangregorio, Claudia Innocenti, Michele Petrecca, Alessandro Lascialfari, Elvira Fantechi, and Francesco Pineider. "Nanometric spinel ferrites: a versatile platform for biomedical and energy applications." Doctoral thesis, 2020. http://hdl.handle.net/2158/1194934.
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Huang, Po-Wei, and 黃柏維. "The Research of Line-Start Permanent Magnet Motors." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/91036825653201280342.
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碩士國立成功大學
機械工程學系碩博士班
96
Induction motors (IMs) have been wildly applied in the industry because of the low manufacturing cost and the simple structure. However, the existence of slip and rotor copper losses will lower the motor efficiency. The structure of Line Start Permanent Magnet Motors (LSPMMs) is similar to IMs, with the permanent magnets inserted in the rotor. Under the synchronous operation, it can provide higher efficiency and be the attractive alternative to the IMs to save electric energy. In the thesis, the equations of cage torque and braking torque are derived to realize the influence of the design parameters, such as input voltage and magnet remanence, at the transient and steady state based on finite element analysis (FEA). In addition, synchronization and loading capability of different rotor designs are simulated to compare the characteristics. Finally, the design with the best performance is introduced to a produced 1HP IM and the improved efficiency is calculated by FEA method. Overall, this thesis provides levant benchmark for LSPMMs design.
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Chen, Han-Syuan, and 陳漢軒. "Research on A Multi-Driven Brushless Permanent Magnet Motor." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/77483830477190750884.
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碩士國立雲林科技大學
機械工程系碩士班
101
This thesis investigates the characteristics of a blushless permanent magnet motor with a novel multi-driving circuit. An experimental prototype is built by rewinding the stator of a commercial motor. Each of the three-phase winding is cut into 3 overlapping sections having 200, 100, and 50 turns of coil, respectively. By using three independent drivers with different combination of duty cycles, the motor can be switched to several different characteristics. The reachable range of speed and torque is significantly widened with this design. An integrated circuit which contains three MOSFET half bridges is used to drive the motor. For the multi-driven motor, three pieces of the driver IC’s are needed. T-N curves of the motor with various combinations of duty cycles are constructed. Efficiency of the multi-driven motor is measured by use of pre-charged super capacitors as the power source. It is found that optimal efficiency can be obtained by setting the ratio of duty cycles for the three drivers to be 4:2:1. Comparisons are also made with a conventional motor.
11
Hsueh, Kai-Fan, and 薛凱帆. "Research of Permanent Magnet Reduction for 40kW Integrated Starter Generator." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/31815900769320028069.
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Wu, Shung-King, and 吳順卿. "The Development and Performance Research of Magnetostrictive Actuators using permanent magnet." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/33344934114421949021.
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碩士國立臺灣大學
機械工程學研究所
88
The aim of this thesis is to develop magnetostrictive actuators using permanent magnet, their magnetic field strength are controlled by mechanisms. By applying the theory of magnetic loop the control factors of magnetic field are derived and dis-cussed. The efficient method of magnetic field control is the variation of cross section area of magnetic loop. Three types of magnetic control mechanisms are developed: the rotary reluctant and the rotary magnetic pole and the dual magnet loop. For per-formance testing and analyzing, The remanent induction of Terfenol-D is firstly measured and its influence on magnetostriction is also studied. Through experimental measuring of magnetostrictive elongation the characteristics of magnetic field control mechanisms are analyzed and researched. The magnetostrictive actuator with Dual magnet loop type can realize a elongation of 3.5 mm. The developed actuators using permanent magnet can actuate precisely and have no heat dissipation.
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Chen, Yi-Hsuan, and 陳逸萱. "Design and Research of Permanent Magnet Reduction for Range-Extender Generator." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/82584275412689583448.
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碩士國立臺灣大學
機械工程學研究所
100
In order to solve the the lack of car mileage and difficult energy supplement for battery electric vehicle (BEV), range-extender electric vehicle (REEV) has been gradually developed. Most common type of range-extender generator is driven by engine with fixed-speed, and the generator must have efficient electrical performance and low torque ripple. Generator and engine operating at steady state under fixed load will not only improve the efficiency of the vehicle power system but also effectively reduce engine exhaust emissions. Therefore, range-extender electric vehicle have better fuel efficiency. According to the results of machine experiments and numeric, this study verified the application of finite element method in the simulation of the motor electrical performance.Then, this thesis applied the finite element method in range-extender generator development process and presented a suitable design process for ISPM machine moreover improved the permanent magnet reduction design. In addition, the study also discussed the impact of different forms of the rotor for the generator permanent magnet reduction results and electrical properties.
14
Tsung-Tai, Cheng, and 鄭宗泰. "Research on Performance Improvement of Micro-Permanent Magnet Synchronous Motor Drive Systems." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/16552311471866695823.
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碩士國立臺灣科技大學
電機工程系
97
This thesis investigates performance improvement of micro-permanent magnet synchronous motor drive systems. Two estimators, which include a state estimator and a rotor position/speed estimator, are proposed. First, the state estimator has been designed to improve the low speed performance of a micro permanent magnet synchronous motor drive system due to its low resolution encoder. Next, a novel position/speed estimator has been designed, which can obtain the position/speed by detecting the zero-current crossing signals. The position/speed estimator combines a zero-current signal processor and a phase angle compensator. In addition, by adjusting the stator current, the low speed performance of the position/speed estimator can be effectively improved. A digital signal processor, TMS320F28335, is used as a control unit to execute the state estimating algorithm and the rotor position/speed estimating algorithm. Experimental results validate the theoretical analysis and show the correctness and feasibility of this thesis.
15
Lin, Ying-Jyh, and 林英智. "Analysis and Research of Cogging-Torque Reduction Method for Permanent Magnet Motor." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/32304298571259031821.
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博士大葉大學
電機工程學系
101
Nowadays, energy shortage is a common problem in our society. Therefore, the research and development of green energy become a critical and important issue. From the view point of mechanical operation, the usage of motor is indispensable. On the other hand, the development of motor also focuses on increasing the efficiency of high power density. In this paper, the development of intelligent motor, namely Brushless permanent magnet brushless DC motor, is proposed. The important characteristics of intelligent motor are its excellent control property, small size, and high efficiency. However, there are some drawbacks associated with it. For instance, the cogging torque can affect the rotation of the motor significantly. Therefore, reducing cogging torque is a vital research issue. This work develops a technique for reducing the cogging torque of a surface-mounted permanent-magnet motor. The method selects appropriate magnet shape parameters, including pole embrace and eccentricity of the outer surface of the magnet that is installed on the rotor of the motor. First, an equivalent magnetic-circuit analysis was performed to develop a six-slot four-pole PM brushless motor design. Then, Fourier series and finite element analyses were carried out to determine the cogging torque, magnetic field, and back-EMF. Based on the results, contours of the cogging torque are plotted for various geometric parameters of the magnet. According to our theoretical analysis, a motor prototype is proposed and developed for measuring the important characteristics of motor. Through our simulation experiments, the performance of the proposed prototype exhibits a highly agreement with the real motor, in terms of its effectiveness and accuracy.
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Yang, Yao-Min, and 楊耀民. "Permanent Magnet generator magnetic flux and Heat Transfer research of the efficiency improvement." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/81879597849696449605.
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碩士國立交通大學
機械工程學系
99
This research aims to improve the efficiency of a permanent magnet generator by increasing the magnetic flux, modifying the heat transfer property, and reducing the weight of the generator. Without changing the outer dimensions of the permanent magnet generator, the structures of the rotor and stator are designed in such a way that the magnetic flux will be increased, the temperature lowered, and the weight reduced. The finite element method is used to perform the above analyses and the power generation efficiency is studied via static and transient approaches. It has been shown in the transient analysis the change of the geometry of silicon steel can increase the magnetic flux density. The creation of holes and addition of cooling fins on the outer surface of the stator can increase heat dissipation and cooling rate. The design of hollow rotor with supporting ribs can reduce weight without affecting the magnetic flux.
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Ji-Ming, Chen, and 陳義明. "The research for direct thrust control of a permanent magnet linear synchronous motor." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/59519820262557661536.
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碩士國防大學中正理工學院
電子工程研究所
96
Recently, the fast developed semiconductor technology and AC motor control theory cause the use of DC motor has been replaced by the AC motor with strong structure and less maintenance gradually. The driving method of AC motor can be divided into scalar and vector control mainly. It is clearly that the vector control is better than scalar control. Generally, vector control includes direct thrust control (DTC) and field-oriented control (FOC). In order to generate proper voltage vector to drive AC motor, the electromagnetic thrust and flux of AC motor were estimated by DTC method and compared with the reference commands. However, since DTC method needs no decoupling computations, DTC is simpler than FOC. Besides, the GA-based PI controller was designed for the position and velocity control. The parameters of this controller were searched by the criteria of fitness function of genetic algorithm (GA). Comparing with conventional method, the obtaining of the parameters of PI controller searched by GA method is more efficient, such as, less search time, improved process, and optimization. In this thesis, the combination of DTC with the GA-based PI controller to achieve force, velocity and position control of permanent magnet linear synchronous motor (PMLSM) has been studied. Finally the validity is verified by simulation and experimental results.
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Tu, Hung-Jan, and 涂弘燃. "Research on Interior Permanent Magnet Synchronous Motor Drive and Rotor Position/Speed Estimation." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/00082456822630946689.
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碩士國立臺灣科技大學
電機工程系
91
The thesis studies a drive system implementation and its rotor position/speed estimation for an interior permanent magnet synchronous motor control system. First, the characteristics and mathematical model of the interior permanent magnet synchronous motor are discussed. Then, the parameters measurement of the motor is proposed. Next, a new rotor position estimator of the interior permanent magnet synchronous motor is discussed. This estimator can easily be realized and it is unrelated to the motor parameters. In addition, the estimating technique only needs the current sensor circuit and does not require any hardware circuit. After that, some computer simulation results are discussed. The implementation of the interior permanent magnet synchronous motor speed control system is developed and based on a digital signal processor. Several experimental results can validate the simulated waveforms and evaluate the correctness and feasibility of the proposed methods.
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Chung, Shu-Wei, and 張書瑋. "High efficiency and low cogging torqueof permanent magnet synchronous motor design applied research." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/19905931897290696778.
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碩士聖約翰科技大學
電機產業研發碩士專班
100
In theinside of the motor are as, the in efficiency of the motor, has been the focus of attention of many people, the use of main stream with the rise of environ mental awareness of today's world, the DC motor, high efficiency, highenergy-saving rate of the world's motor. Focus on the direction of this thesis,the best design for brushless DC motors, brushless DC motor with high torque, high power density characteristics, the appropriate electronic commutation allows it to high, such as DC motor performance operating characteristics,application of the servo system has become the main current. This paper aims of profit RMxprt analysis software, permanent magnet brushless DC synchronous machine proto type to construct a preliminary analysis; the study were analyzed using an 10 pole 12 slot rotor structural design, 75mm x 75mm x 48mm diameter,thickness 20mm stator through the experimental data measured by the measurement, analysis to optimize the experimental results;, Maxwell_2D analysis of static magnetic magnetic field to investigate the degree of saturation, stator silicon steel to save the cost of materials to achieve con side rations; while taking advantage of the optimum ratio of the best magnet repair arc lower magnet cogging torque generated to reduce the jitter to happen. Comparison of 10 pole12 slot the inner diameter of 48mm bring the best ratio to verifythe analysis method of high efficiency and low torque brushless DC motor.
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Chang, Chi, and 張繼. "Research on GaN-based Power Devices Applied in Permanent Magnet Synchronous Motor Drive." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/763w44.
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碩士國立臺灣大學
工程科學及海洋工程學研究所
106
In this paper, wide-bandgap (WBG) gallium nitride (GaN)-based power devices were used to replace the traditional silicon power device to increase the switching speed of the power device and reduce the switching loss and conduction loss of the three-phase inverter. Therefore, we can use gallium nitride (GaN)-based power devices to increase the power conversion efficiency of the permanent magnet synchronous motor control system and improve the heat dissipation of the three-phase inverter. LTspice circuit simulation software were used to analyze the three-phase inverter circuits with traditional silicon power devices and gallium nitride (GaN) power devices. Gallium nitride (GaN) power devices can reduce switch on-time and switch-off time by 90%, and it also reduce the switching loss of 89% in the inverter when the load current is 8(A). By using MATLAB / Simulink, space vector pulse width modulation (SVPWM), vector control, permanent magnet synchronous machine (PMSM) and control system were combined to simulate the system response such as motor speed, voltage and current waveform of permanent magnet synchronous motor control system. We also use micro-control board and gallium nitride (GaN) power module to implement the permanent magnet synchronous motor control system. Verify that wide-bandgap (WBG) gallium nitride (GaN)-based power devices can be applied to the permanent magnet synchronous motor control system. We also compare the different between the GaN and Si motor control system. The GaN motor control system reduce the total power loss of 1440mW and up to 85.27% efficiency when the motor load is 0.2Nm. The GaN inverter also achieve 95.116% efficiency. Finally, the permanent magnet synchronous motor control system with higher switching speed and better power conversion efficiency is built.
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Hsiao, Yi-Hsuan, and 蕭逸軒. "Research of Permanent Magnet Synchronous Motor Control Strategies in Electric Power Steering System." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/p9bsnv.
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碩士國立臺灣大學
電機工程學研究所
106
The developing process of steering system has experienced from the simple mechanical steering system (MS), hydraulic steering system (HPS) to electric-hydraulic steering system (EHPS), till the electric power steering system (EPS) with lower energy consumption and higher performance. With the rapid development of power electronics and electric vehicles, EPS system have been found in more and more applications. This thesis aims at the performance of permanent magnet synchronous motor (PMSM) control strategies in EPS system. Firstly, the dynamic model and assisting curve are established by analyzing the simplified model structure and standard assist logic of the EPS system. Then the coordinate transformation is used to derive the mathematical model of PMSM under different reference frames, which take part in the design of three different vector control strategies: Field Oriented Control (FOC), Direct Torque Control (DTC) and Direct Torque Control with Space Vector Modulation (DTC-SVM). In order to verify the effect of the control strategies proposed in this thesis, MATLAB/Simulink is used to build three different types of EPS system, and confirm the characteristic of the control strategies mentioned above through simulation results in different scenarios.
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Wang, Xiaoguang, and 汪曉光. "Preliminary Design and Research on Cogging Torque of Surface Mounted Permanent Magnet Brushless DC Motor." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/mee5nc.
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碩士國立臺灣大學
電機工程學研究所
105
The Brushless Direct Current Motor(BLDCM) has attracted more and more attention because of its advantages such as small size, high efficiency, easy maintenance, and good speed performance. Because the BLDCM uses permanent magnet excitation, the interaction between the rotor magnets and the stator teeth of the machines will produce cogging torque. It is a kind of torque that is caused because of its own structure. It will be generated even when there is no armature current. Cogging torque will cause parasitic ripples which further leads to mechanical vibration and acoustic noise. In addition, it has a certain influence on the accuracy and performance of the speed control system and position control system. Therefore, it is of great significance to study methods to mitigate the cogging torque of BLDCM. Firstly, this thesis introduces the research status of BLDCM, and summarizes the current research situation of the cogging torque weakening method at home and abroad. The basic structure and operating principles of BLDCM are introduced in detail. The mathematical model and operating characteristic curve of the motor are obtained by theoretical deduction. Secondly, the mechanism of the generation of cogging torque is analyzed by diagrams, and four main analysis methods of cogging torque are introduced, they are Flux-MMF graph method, energy method, Maxwell tensor method and FEA method. The derivation of cogging torque expression based on energy method and Fourier transform is especially introduced. Thirdly, the principle and characteristic of equivalent magnetic circuit method is introduced. The design process of electromagnetic parameters of motor is studied. On the basis of the electromagnetic p arameters design theory of BLDCM, a continuous operation BLDCM, which rated power is 30W, rated voltage is 24V, rated speed is 1350rpm, is designed. The rationality of the design result is verified with the ANSYS Maxwell design software. Fourthly, the commonly used finite element method for electromagnetic field analysis is introduced, and the finite element analysis software ANSYS Maxwell is briefly introduced. Based on the expressions of the cogging torque deduced from the energy method and the Fourier transform. This paper first discusses the influence law of seven aspects including the stator slot width, permanent magnet pole arc coefficient, slots per pole in theory. Then each method is applied to the 12 slot 10 pole motor designed in this paper. The simulation is carried out by using ANSYS Maxwell software, and the correctness of each method is verified. Finally, an important parameter optimization method called genetic algorithm is introduced. Using ANSYS Maxwell genetic algorithm analysis module, the combination parameters of the slot width, pole arc coefficient and magnetic pole thickness is optimized. The results show that the combined parameter optimization can greatly reduce the cogging torque.
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Huang, Da-Cyun, and 黃達群. "A Research on Improved PDFF Controller for the Permanent Magnet Synchronous Motor Speed Command Tracking Control." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/q9j2y2.
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碩士國立中央大學
電機工程學系
104
A pseudo derivative feedback with feed forward gain (PDFF) controller combined with an adaptive fuzzy controller is proposed in this study in order to improve the speed command tracking error and transient response of a permanent magnet synchronous motor (PMSM). The speed tracking performance attained using two improved versions of the PDFF controller, which incorporate a compensation fuzzy controller and a parameter adjusting fuzzy controller respectively, are also compared in this study. Traditional field oriented control methods used to control the motor speed or position is generally achieved by adjusting a proportional integral (PI) controller. The PI controller has the advantages of a simple algorithm and excellent transient response, but causes overshoot and low DC stiffness. Therefore, the pseudo derivative feedback (PDF) controller is proposed to improve the aforementioned drawbacks of the PI controller. It has high DC stiffness and no overshoot, but is seriously constrained in many applications due to its slow transient response. The unique feature of the PDFF controller is that it can become a PI or PDF controller by adjusting the feed forward gain. Thus, a flexible transient response can be obtained. In order to increase the speed command tracking performance of the PDFF controller, an adaptive fuzzy controller is used to control the speed error, which is the input of the PDFF controller. In addition, the adaptive control law is derived by the gradient descent method, thereby enabling the rules of the fuzzy controller to update online in real time; the learning ability drawback of a fuzzy controller is thereby improved in this study. Finally, the proposed methods were implemented in the PSIM simulation and also validated in the digital signal processor (DSP) TMS320F28335 experimental results.
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Lai, Young-Ren, and 賴泳任. "The Research of Design and Simulation of the H∞ Control for Direct-Driven Permanent Magnet Synchronous Wind Generator." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/464v8d.
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碩士正修科技大學
電子工程研究所
106
In this paper, the robust control of direct-drive permanent magnet synchronous wind generator (PMSG) is studied, which considers that the direct-drive permanent magnet synchronous wind turbine is a nonlinear system in actual operation. Besides, at the same time under the realistic problems of uncertainties of system parameters and external disturbances, the mathematic model of direct-drive permanent magnet synchronous wind power generation system is established. Among them, the H∞ control theory and the direct feedback linearization technique are used. By using the way the robust control model is set up, the control law is obtained by H∞ control theory, and the algorithm is concise and practical. The results of MATLAB/Simulink simulation show that H∞ control can make sure the direct-drive permanent-magnet wind-driven synchronous generator can obtain maximum wind energy safely and reliably, and also transmit constant-voltage and constant-frequency power to the power grid in the case of wind speed change, uncertain system parameters and external disturbances.
25
Li, Meng-Chieh, and 李孟杰. "Research on the Effects of Heat Transfer Numerical Simulation on the Permanent Magnet of Electric Vehicle and the Improvement of Heat Dissipation System." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/434xj6.
Full textAbstract:
碩士國立臺北科技大學
車輛工程系所
102
Energy consumption and air pollution are the issues which been discussed in recent years, the development of electric vehicles is regarded as the key to solve this problem, but to coMPare with traditional motor, the elect motor need more power and lower volume and to meet these requirements the problem "heat dissipation" show up. The purposes of this research are to establish a permanent magnet motor thermal model and an improvement for the cooling system. In the research will use the computational fluid dynamic(CFD) instead of heat resistance of the physical modeling due to numerous internal components and itself complex geometry of permanent magnet motors. The CFD is to discrete the model to several regions and these regions are mold by elements and nodes then to use the appropriate algorithm for the result. This research of the motor thermal model especially regard to the reflection of the heat transfer in motor''s air-gap and the contact heat resistance between stator and shell then insert the result to the motor thermal model. The result of flowfield analysis found that it’s not easy to do the heat dissipation on original motor due to the fin type and it got better outcome when change to flat fin type which experiment via Taguchi experiment method. By this way it can substantially decreases the temperature.