一种开关磁阻电机模糊PI的直接瞬时转矩控制

噪音是开关磁阻电机应用中的一大难题。针对开关磁阻电机运行过程中转矩脉动较大的问题,采用有限元计算方法所得到的电机模型,在MATLAB中进行开关磁阻电机模糊PI直接瞬时转矩控制的仿真实验。采用Ansoft电磁场仿真软件,搭建了三相4/6开关磁阻电机,并将得到的磁链数据导入MATLAB电机模型中。随后,利用该模型搭建模糊PI直接瞬时转矩控制的Simulink仿真实验平台。实验结果发现,系统在0.01 s时开始响应,转矩浮动在0.05~0.1 Nom之间。该结果表明,将有限元得到的电机模型应用到模糊PI直接瞬时转矩控制的仿真实验中时,可以提高系统响应,并有效抑制转矩脉动。     

开关磁阻电机的直接转矩控制系统的仿真研究

通过对开关磁阻电机的控制方法的介绍,引入了直接转矩控制技术,并对直接转矩控制进行了分析.并通过matlab搭建的仿真模型,验证了该控制系统的优良性能,取得了较好的控制效果,明显地减少了转矩脉动,提高了系统的调速性能.     

开关磁阻电机优化设计方法的研究

开关磁阻电机的主要缺点是运行时转矩脉动、噪声和振动比较大,要改善它的性能一般从电机本体结构优化和电机控制优化两个方面进行。本文主要从电机结构尺寸和参数优化设计方面,阐述使开关磁阻电机转矩脉动、噪声和振动降低的方法以及发展趋势。     

在线转矩分配函数控制开关磁阻电机策略分析

开关磁阻电机(SRM)因双凸极结构,其内部磁场非线性导致运行过程中会产生较大的噪声和转矩脉动。根据开关磁阻电机数学模型,以四相8/6极SRM作为研究对象,用Matlab/Simulink搭建基于在线TSF策略的转矩脉动控制系统模型。系统将实时转矩跟踪参考转矩,将不确定性因素进行整体逼近减小误差,实现在线TSF控制。仿真结果表明,所提系统建模方法能有效地抑制转矩脉动,并增加其稳定性,为实际电机控制系统的设计提供新的思路及参考依据。     

基于BP神经网络的开关磁阻电机直接转矩控制建模与仿真

开关磁阻电机具有特殊的双凸极结构,导致其运行时会产生严重的转矩脉动,直接转矩控制可显著降低转矩脉动。但由于磁路的严重饱和,传统方法利用公式计算转矩过程非常复杂,提出一种基于BP神经网络来预测开关磁阻电机转矩,进而进行直接转矩控制的策略。通过有限元仿真得到训练数据经离线训练之后,即可得到输入量到转矩的非线性映射,该控制方法利用BP神经网络泛化、逼近能力强的优点,省去了复杂的转矩计算,同时可以对转矩脉动进行抑制。仿真和实验结果表明,该方法响应速度快,控制精度高。     

基于转矩逆模型的SRM转矩脉动抑制研究

开关磁阻电机转矩逆模型的精度对于采用电流控制方式实现转矩控制的系统有很大的影响,文中采用经细菌群体趋药性算法优化后的最小二乘支持向量机建立开关磁阻电机的转矩逆模型,获得电流-转矩-角度特性;进而结合转矩分配函数和电流控制环构SRM转矩控制系统。通过仿真实验表明,该转矩逆模型准确地反映了电机的电流-转矩-角度特性,提高了开关磁阻电机控制系统中电流控制环的精度,并对该系统转矩脉动的抑制有重要作用。     

基于软开关技术的永磁同步电机直接转矩控制系统

给出了永磁同步电机直接转矩控制的系统结构,提出了直接转矩控制技术与变流器软开关技术相结合的方法.电机控制系统综合了直接转矩控制快速特性和软开关的低开关损耗特性,以提高电力电子器件开关频率从而减小永磁同步电机的转矩脉动,最后给出了控制系统的计算机仿真.     

基于转矩分配函数的开关磁阻电机的控制

转矩脉动较大是开关磁阻电机(SRM)的主要缺点,为了减小转矩脉动,提高电机性能,将转矩分配策略应用到电机中,能有效抑制转矩脉动。但由于开关磁阻电机的非线性,使得设计转矩分配函数变得很困难,传统的线性函数虽然简单,但无法体现开关磁阻电机的非线性。虽然非线性正弦函数的提出使得转矩性能得到了提高,但在换相区的效果还是不尽理想。为了解决这个问题,文中提出一种滞环补偿性转矩分配函数,仿真证明了该方法的有效性。     

低开关频率下直接转矩控制转矩脉动抑制方法

本文针对直接转矩控制中转矩脉动大以及开关频率不恒定的问题,深入分析了感应电动机的定子磁链和转矩的实际变化情况,提出了在低开关频率下抑制转矩脉动的新型方案,仿真结果验证了新方案能够有效减小低速时转矩脉动并降低高速时开关频率。     

基于A-2-SMC开关磁阻电机直接转矩控制

文中针对开关磁阻电机转矩脉动大及其控制系统难以实现快速精确调速的缺点,提出了一种自适应二阶滑模控制与直接转矩控制相结合的复合控制方案,并对该方案中的自适应二阶滑模控制器进行设计。该控制器采用超螺旋算法,同时对其增益采用自适应调节,克服了传统二阶滑模控制器增益确定依赖于扰动导数界值的缺点。仿真结果表明,文中所采用的控制方案不仅能对电机转速实现快速精确控制,而且能对电机转矩脉动进行有效抑制。     

Torque ripple minimization in switched reluctance motor drives byPWM current control

Higher torque ripple is one of the few drawbacks of switched reluctance motor (SRM) drives which otherwise possess excellent characteristics for applications in many commercial drives. This paper begins with an extensive review of torque ripple reduction methods that appear in the literature and then presents a new strategy of PWM current control for smooth operation of the drive. This method includes a current control strategy during commutation when torque ripple minimization is of utmost importance     

基于SVPWM的永磁同步电机直接转矩控制系统的建模与仿真

文章介绍了永磁同步电机直接转矩控制的原理,分析了传统直接转矩控制系统转矩脉动的缺点,并且将空间矢量脉宽调制技术引入永磁同步电机的直接转矩控制系统中,利用空间矢量的调制过程,可在相同的系统硬件条件下得到更多的、连续的电压空间矢量,进而得到对电机更准确的控制。仿真结果表明,该方案既保持了直接转矩控制快速动态响应,又减小了电机转矩的脉动。     

Variable structure control of an SRM drive

The applications of a variable-structure system (VSS) to the control of a switched reluctance motor (SRM) drive is presented. After reviewing the operation of an SRM drive, a VSS-based scheme is formulated to control the drive speed. The scheme is then designed and tested by simulation. The results show that the VSS control is effective in reducing the torque ripple of the motor, compensating for the nonlinear torque characteristics, and making the drive insensitive to parameter variations and disturbances     

Computation of optimal excitation of a switched reluctance motorusing variable voltage

This paper investigates the optimal excitation of a switched reluctance motor, such that overall drive efficiency is maximized under a variable supply voltage. The result presented in the paper exhibits the improved drive efficiency and the expanded range of operating torque and speed. Furthermore, the variable supply voltage may be utilized in reducing torque ripple     

异步电动机直接转矩控制的仿真研究

根据直接转矩控制的基本原理,在MATLAB环境下,建立异步电动机直接转矩控制系统仿真模型,针对异步电动机转矩脉动大等问题,采用转矩三点式调节器及12区段磁链划分方法仿真结果表明,该方法可有效地减少转矩脉动,提高直接转矩控制系统的性能。     

Fault-tolerant switched reluctance motor drive using adaptive fuzzy logic controller

An adaptive fuzzy controller has been designed to develop a high-performance fault-tolerant switched reluctance motor (SRM) drive. The fuzzy controller continuously adapts its properties to regulate the machine torque as desired by the drive system even under fault conditions. The adaptation of the fuzzy membership functions results in extended conduction period and increased peak current of the healthy phases to deliver the commanded torque, as much as possible. The adaptive fuzzy controller provides smooth torque output with minimum ripple, even under fault conditions, yielding a high-performance SRM drive with fault-tolerant capability.     

Control of switched reluctance drives for electric vehicleapplications

Dynamic controllers of switched reluctance drives adjust at least three variables, i.e., current amplitude, turn-on, and turn-off angles. In electric vehicle (EV) applications high efficiency of the drive over a wide speed range, wide torque bandwidth, and low torque ripple under varying DC-bus voltage conditions are important design goals. Hence, controllers of switched reluctance drives for EVs usually have a complex structure. In this paper, the demands on control accuracy of switched reluctance machine traction drives and the traction controller sampling frequency, which are necessary to take advantage of the switched reluctance machine dynamic capabilities, are discussed. To integrate the traction drive, the control commands need to be actualized with a sampling frequency of at least 100 Hz to meet the high-dynamic requirements of modern vehicle control systems, e.g., active cruise control, antislip control, and active damping of mechanical drivetrain oscillations. It is found that the switching angles have to be adjusted within one-tenth of a mechanical degree. This study shows that switched reluctance drives can fulfill all requirements needed for electric propulsion using standard microcontrollers or digital signal processors