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Modelling and Simulation of SVPWM Inverter Fed Permanent Magnet Brushless DC Motor Drive  [PDF]
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering , 2013,
Abstract: Variable speed drives with Pulse Width Modulation are increasingly applied in many new industrial applications for more efficient performance. Recently, developments in power electronics and semiconductor technology have lead to widespread use of power electronic converters in the power electronic systems. A number of Pulse width modulation (PWM) schemes are used to obtain variable voltage and frequency supply from a three-phase voltage source inverter. Among the different PWM techniques proposed for voltage fed inverters, the sinusoidal PWM technique has been popularly accepted. But there is an increasing trend of using space vector PWM (SVPWM) because of their easier digital realization, reduced harmonics, reduced switching losses and better dc bus utilization. This paper focuses on step by step development of SVPWM implemented on a PMBLDC motor. Simulation results are obtained using MATLAB/Simulink environment for effectiveness of the study.
Torque ripple reduction strategy for magnet suspended reactive flywheel brushless DC motor

- , 2016, DOI: 10.13700/j.bh.1001-5965.2015.0451
Abstract: 摘要 无磁链反馈直接转矩控制(DTC)因转矩响应速度快,为小电感磁悬浮反作用飞轮(MSRF)无刷直流电机(BLDCM)的转矩脉动抑制提供了可能,但其bang-bang控制器使电机转矩脉动较大。为解决此问题,对影响转矩脉动的换相和非导通相续流过程进行了数学建模,并得出电机转矩与绕组电流的关系,提出一种基于转矩预测的转矩控制方法,能够有效减小转矩脉动,并证明了所提策略的稳定性和鲁棒性。在采用滑模观测器(SMO)进行反电动势估计时,提出一种新的带有参数的光滑连续函数替换符号函数,有效地抑制了滑模观测器的抖振现象。仿真和实验结果表明,所提出的基于改进滑模观测器和转矩预测的改进转矩控制方法相对于传统直接转矩控制能够更好地抑制转矩脉动,而且转矩响应速度基本不变。
Abstract:Due to its high torque response speed, direct torque control (DTC) without flux feedback makes the torque ripple reduction of magnet suspended reactive flywheel (MSRF) brushless DC motor (BLDCM) possible, which has a small inductance. However, the bang-bang controller of the DTC causes high torque ripples. To solve this problem, the mathematic models of commutation and diode freewheeling of the inactive phase were established and the relationship between torque and phase current was obtained.Then a torque prediction method based on the established models was proposed to reduce the torque ripple effectively, and the stability and robustness were proved. While estimating the back electromotive force of the BLDCM with sliding mode observer (SMO), a smooth and continuous function with one parameter was employed to replace the sign function which leads to a higher back electromotive force estimation accuracy. Simulation and experimental results show that compared to the traditional DTC, the advanced torque control method with torque prediction and advanced SMO can significantly suppress the torque ripples and has almost the same torque response speed.
A Reset Particle Swarm Optimization PID Control of Permanent Magnet BLDC Motor for Airscrew Load

- , 2016,
Abstract: 永磁无刷直流电机驱动高空螺旋桨负载时,由于大气密度随海拔高度变化,电机转速随螺旋桨负载变化不断波动,传统定参数PID控制难以随环境变化对电驱动系统PID控制参数进行实时调整,系统的动态特性和鲁棒性较差。提出一种基于BFGS(Broyden-Fletcher-Goldfarb-Shanno)动态重置粒子群算法(BFGS-RPSO)的永磁无刷直流电机PID参数控制方法,该方法利用BFGS-RPSO算法灵活快速的在线参数寻优特点,对永磁无刷直流电机控制系统PID参数进行在线实时优化调整,提高了螺旋桨负载电驱动系统的动态特性和鲁棒性。Matlab仿真和实验表明,电机在起动过程中,转速上升时间较短,转速和转矩超调较小,且在负载波动过程中电机转矩脉动较小,BFGS-RPSO PID参数控制比传统PID 控制具有更好的动态特性和鲁棒性,适合应用于高空螺旋桨永磁无刷直流电机螺旋桨电驱动系统。
When permanent magnet brushless DC motor (PMBLDCM) drive high altitude airscrew load, due to the change in atmospheric density with altitude and the frequent fluctuations of airscrew load torque, the traditional given-parameter PID control meets difficulty in the real-time adjustment of the PID parameters of electric power drive systems (EPDS) with environmental change; so the dynamic characteristics and robustness of system is poor. To solve the problem, a novel PID control method based on the BFGS-RPSO algorithm is proposed. The method uses of flexible global and fast local search optimization of BFGS-RPSO algorithm to online optimize the PID parameters of PMBLDCM control system and improve the dynamic characteristics and robustness of electric drive systems with airscrew load. Matlab simulation and experimental results show that the rise time of speed is shorter and the overshoot of speed and torque is less during starting the motor. Besides, the torque ripple is smaller in load fluctuation. The dynamic characteristics and robustness of BFGS-RPSO PID parameter control are better than those of traditional PID control. The method is feasible for the EPDS of PMBLDCM with propeller load
Dynamic Surface Control for Permanent Magnet Brushless DC Motor Speed Servo System

- , 2017,
Abstract: 为满足超燃冲压发动机燃油供应系统对电动泵用电机驱动控制精度和响应速度的要求,提出一种新颖的基于扩张状态观测器的动态面控制策略,应用在无刷直流电机(BLDCM)转速伺服系统,有效克服了无刷直流电机的参数摄动和负载扰动。建立基于相电流的电机动态模型,通过扩张状态观测器,在外部扰动模型未知的情况下,观测电机负载转矩用于构造动态面控制器,并证明闭环系统转速一致最终稳定。仿真和试验结果表明,与经典PID控制方法相对比,动态面控制策略显著提高了无刷直流电机转速伺服系统的闭环精度和动态性能,对电机参数摄动和负载扰动具有良好的抑制作用。
Due to the requirements of control precision and response speed for pump motor drive applied to scramjet fuel feed system, This paper proposes a novel dynamic surface control (DSC) base on extended state observer (ESO) applied in the brushless DC motor (BLDCM) speed servo system. This method solves the problem of the variation of motor parameters and the disturbance of load torque. A simplified dynamic model of BLDCM is designed based on the phase currents. By the ESO, the torque of BLDCM can be evaluated exactly with partially unknown states of external disturbance, and a controller is developed through the DSC technique. A stability analysis is given, showing that the control law can guarantee uniformly ultimate boundedness of the solution of the closed-loop system. Compare with the traditional PID controller, the simulated and experimental results show that the control precision and dynamic performance of the system can be significantly improved by using the proposed strategy. Furthermore, the robustness for changes of motor parameters and load torque disturbance can be guaranteed
SVPWM调制策略下永磁同步发电机损耗分析  [PDF]
- , 2016,
Abstract: 永磁同步发电系统中,发电机与PWM变流器直接相连,使永磁同步发电机谐波损耗增大,甚至会导致永磁材料不可逆去磁.针对该问题,本文利用AnSoft联合仿真研究了基于矢量控制的SVPWM调制策略下,设置不同调制比与载波频率对永磁同步发电机铜耗、铁耗及转子损耗的影响,并深入分析了损耗随调制比与载波频率变化的规律.仿真结果表明:SVPWM调制策略下的PMSG-PWM系统中,载波频率一定时,随着调制比的增大,永磁同步发电机铜耗、铁耗及转子损耗逐渐减小,且调制比每增加0.1对发电机铜耗的影响最大;调制比一定时,永磁同步发电机的铜耗、铁耗及转子损耗也逐渐减小,但载波频率每增加1 kHz,对发电机铁耗及转子损耗的影响最大.研究结果为SVPWM调制策略下设定合理的调制比与载波频率以保障永磁同步发电机的安全运行提供了参考.
Permanent magnet synchronous generator is directly connected with PWM converter in the wind power system based on direct-driven permanent magnet synchronous generator, which results in the increase of the stator losses of the permanent magnet synchronous generator, and even leads to the irreversible demagnetization of permanent magnet materials. To solve this problem, this paper analyzed the influence of amplitude modulation radio and frequency modulation radio on eddy current losses and stator losses of permanent magnet synchronous generator under SVPWM modulation. Finally, this paper compared the results of AnSoft simulation and Fourier analysis with the results obtained from the calculation models of this paper, which verifies the correctness of the calculation model proposed. The calculation models presented have reference value for setting proper amplitude modulation radio and frequency modulation radio under SVPWM modulation. This can ensure the safe operation of the permanent magnet synchronous generator.
Performance Evaluation of Direct Torque Control with Permanent Magnet Synchronous Motor  [cached]
Bindeshwar Singh
Buletin Teknik Elektro dan Informatika , 2012,
Abstract: The direct torque control theory has achieved great success in the control of permanent magnet synchronous motor. A Direct Torque Control (DTC) scheme of Permanent Magnet Synchronous Motor (PMSM) is presented. Based on in-depth analysis of PMSM mathematical model in abc frame and frame are established and the operation principle of DTC-SVPWM system, the relationships between the torque and fundamental components. A novel space vector pulse width modulation (SVPWM) method which has a feature of low harmonic is proposed. The proposed method is adopted to implement the direct torque control (DTC) of a three-phase PMSM. A large number of simulation results show that the DTC System of PMSM has fast response and good dynamic performance. Aiming at the direct torque control in PMSM Drives, in this paper explained the theoretical basis of the direct torque control (DTC) for PMSM firstly. Then explained the difference between the applications of DTC-SVPWM to PMSM. Finally the MATLAB/Simulink models were developed to examine the DTC- SVPWM for PMSM. The simulation results is presented in this paper.
Analysis of the High-Speed Permanent Magnet Brushless DC Motor for Electric Supercharger System

- , 2016,
Abstract: 由高速驱动电机与压气机组成的电动增压系统,空气经系统压缩进气缸参与燃烧以提升动力输出。但高速电机的高损耗密度和高频特性会引起永磁体高温退磁和绕组阻感变化,不利于系统长时间稳定工作。基于受阻感影响小的基波/三次谐波磁链复合信号设计了新型高速电机无位置控制策略。同时在电机设计时将提升三次谐波信噪比,减小转子径向力和涡流损耗作为优化目标,对极弧系数等电机结构参数进行了设计优化。采用三维温度场方法分析电机温升,发现不同阶段热量传播路径存在不同。样机性能实验显示系统负载运行动态响应迅速,有效降低动力迟滞;温升实验结果表明热平衡时永磁体温度远低于极限温度,可靠性提升;亦验证了热量传播路径的观点。
The electric supercharger system which is decoupled from the combust engine naturally, is composed of a high-speed brushless DC motor and a compressor. However the high loss density of high-speed motor would cause the heat concentration and demagnetization, also the resistance-inductance of winding is liable to get affected by high frequency, which generates commutation errors. In this paper, a novel sensorless control consisted of fundamental and 3rd harmonic flux is proposed. Simultaneously, rising the signal-to-noise ratio of 3rd harmonic flux, reducing the radial force of rotor and decline in motor loss and temperature rising are employed as the conditions, to optimize main parameters such as pole arc to pitch ratio. Three dimensional temperature field calculation method is adopted and heat propagation paths are different in different temperature rising stages is revealed. Performance experimental results of load condition indicate that the dynamic response of system is swift. The temperature of permanent magnet is much lower than the limited temperature, the view of heat propagation path is also verified
Comparative analysis of SPWM and SVPWM control for three phase inverter  [PDF]
K. Vinoth Kumar,Prawin Angel Michael,Joseph P. John,S. Suresh Kumar
Journal of Engineering and Applied Sciences , 2010,
Abstract: A voltage source inverter is commonly used to supply a three-phase induction motor with variable frequency and variable voltage for variable speed applications. A suitable pulse width modulation (PWM) technique is employed to obtain the required output voltage in the line side of the inverter. The different methods for PWM generation can be broadly classified into triangle comparison based PWM (TCPWM) and Space Vector based PWM (SVPWM). In TCPWM methods such as sine-triangle PWM, three phase reference modulating signals are compared against a common triangular carrier to generate the PWM signals for the three phases. In SVPWM methods, a revolving reference voltage vector is provided as voltage reference instead of three phase modulating waves. The magnitude and frequency of the fundamental component in the line side are controlled by the magnitude and frequency, respectively, of the reference vector. The highest possible peak phase fundamental is very less in sine triangle PWM when compared with space vector PWM. Space Vector Modulation (SVM) technique has become the important PWM technique for three phase voltage source inverters for the control of AC Induction, Brushless DC, Switched Reluctance and Permanent Magnet Synchronous Motors. The study of space vector modulation technique reveals that space vector modulation technique utilizes DC bus voltage more efficiently and generates less harmonic distortion when compared with Sinusoidal PWM (SPWM) technique. In this paper first a model for Space vector PWM is made and simulated using MATLAB/SIMULINK software and its performance is compared with Sinusoidal PWM. The simulation study reveals that Space vector PWM utilizes DC bus voltage more effectively and generates less THD when compared with sine PWM.
一种数字化SVPWM算法的研究  [PDF]
福州大学学报(自然科学版) , 2014,
Abstract: 从逆变器交流侧各电压矢量之间的关系出发,根据SVPWM控制策略的基本思想,提出一种数字化的SVPWM算法,可以快速、准确地完成计算. 利用PSCAD软件对采用不同SVPWM算法的逆变器进行仿真研究,通过实验验证了该算法的有效性.
Simplified Algorithm of Three-Level SVPWM with DSP

徐进, 邹爱龙, 刘婉丽
Clean Coal and Energy (CCE) , 2014, DOI: 10.12677/CCE.2014.24006
This paper researches the three-level SVPWM algorithm with DSP. In order to simplify the section judgment and the time calculation of space vector, save the resource of DSP and improve the per-formance, this paper presents a method that divides the space vector into 6 small hexagon space vectors. In each small hexagon, the same algorithm of two-level SVPWM is used to judge the triangle section and calculate the time of vector. This method simplifies the three-level SVPWM and improves the performance.
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