Proposition of new mathematical models with stator core loss factor for induction motor

This paper proposes new mathematical models with stator core (iron)‐loss factor for induction motors intended to generate precise and/or efficient torque via vector control. The proposed models have a structure in which the stator core‐loss resistance is equivalently placed purely in parallel with the stator inductance. It is shown that stator core losses consisting of eddy‐current and hysteresis losses can be properly represented by the parallel resistance, and, in particular, eddy‐current loss by a constant one. The models are composed of three basic vector equations in the general frame of an arbitrary angular frequency, such as fourth‐order differential equations describing motor dynamics, the torque equation, and the energy conversion equation. These basic equations are essential for vector control design taking core loss into consideration. The proposed models are most compact in the sense of the number of both the employed parameters and the interior states of the motor. Compactness is an important factor for modeling and is useful for designing vector control systems. © 2000 Scripta Technica, Electr Eng Jpn, 134(1): 64–75, 2001     

一种十五相感应电机的矢量控制算法

在已有多相电机系统研究的基础上,研究了一种新型的十五相感应电机矢量控制算法.详细推导了该种十五相感应电机的数学模型,并在此基础上推导了十五相感应电机的矢量控制算法,给出了系统的控制框图.系统试验结果表明了该矢量控制算法的正确性和可行性,将该算法应用于实际的十五相感应电机矢量控制系统中,可以取得对电机良好的控制效果,该十五相感应电机矢量控制算法可直接应用于兆瓦级大功率十五相感应电机系统中.     

笼型转子断条感应电动机的易解数学模型

针对断条破坏了电机原有对称关系而使建模仿真变得困难,采用综合矢量法,建立了转子断条感应电动机易于求解的数学模型.对电机暂态及稳态仿真揭示了定子电流幅值与转矩随时间脉动的故障特征,得出了转子导条电流分布规律,表明与断条相邻及相距一对极距的导条电流最大.引人关注的是在转子端环间出现端电压,其值反映了转子电路不对称程度;揭示了故障特征随电机负载变化规律.定子电流实测与仿真结果相吻合证实了结论正确,有助于感应电机在线故障诊断.     

双定子笼型感应电动机的数学模型及性能计算

对双定子笼型感应电动机建立了数学模型,进行了性能分析与计算,利用Ｃ＋＋语言编制了计算机辅助设计程序,并设计与试制了两台２２ｋＷ、６极的模型机,通过实验证明了理论分析与计算的正确性。     

矢量控制异步电动机的自适应控制和参数辨识

在矢量控制异步电动机数学模型的基础上，针对电机转子电阻和负载转矩变化的不确定性，应用非线性控制的理论，设计了一个渐近跟踪负载转矩和转子电阻实际值的非线性辨识算法，实现了参数的自动跟踪，并建立了非线性自适应控制的方案。仿真结果表明，辨识算法具有快捷准确的优点，使系统具有一定的鲁棒性和较好的稳、动态性能。     

异步电动机无速度传感器的矢量控制

对交流异步电动机无速度传感器的矢量控制进行了综述 ,分析了几种控制方案的原理 ,指出了它们各自的优点与不足 ,并就今后的研究发展方向提出了一些设想     

异步电机无速度传感器矢量控制系统的研究

为了实时辨识电动机的转子转速,提出利用在异步电机端测量得到的电压和电流来估算电机转速,以实现无速度传感器矢量控制的模型参考自适应方法.在MATLAB/Simulink中,建立了一个基于该方法的无速度传感器矢量控制系统,并进行了仿真实验,仿真结果表明该系统具有良好的动静态特性和稳定性.     

感应电机控制策略综述

介绍了感应电机控制策略的发展,对转速开环恒压频比控制、磁场定向矢量控制、直接转矩控制、反馈线性化控制、滑模变结构控制与智能控制等控制策略进行了理论与实际运用的探讨,并分析了各种控制策略的优缺点,提出控制策略的发展方向。     

无速度传感器异步电机矢量控制系统的改进研究与仿真

以异步电机矢量控制的基本方程式为基础,构建了一个无速度传感器矢量控制系统。系统采用了改进积分型转子磁链估算模型。根据模型参考自适应方法的原理,提出一种改进的速度估算法。并利用MATLAB/SIMULINK进行了仿真,仿真结果验证了采用的速度估算方法是正确的。     

大功率感应电机矢量控制系统软硬件设计

根据大功率感应电机矢量控制的特点,设计了一种基于浮点型数字信号处理器ＴＭＳ３２０Ｃ３１和单片机８０Ｃ１９６ＭＣ的双微机矢量控制系统,并详细说明了其软硬件设计方法。实验结果表明,该控制系统充分利用了ＴＭＳ３２０Ｃ３１和８０Ｃ１９６ＭＣ的特点,软硬件设计合理、实时性好,能可靠地完成复杂的矢量运算和优化 ＳＰＷＭ波形生成,控制感应电机达到较好的动态性能。     

基于感应电动机复数简化模型的参数辨识研究

感应电动机数学模型的非线性、强耦合和模型中不可观测量的存在,使得在辨识电机参数时需要求解复杂的非线性微分方程组而导致辨识困难。提出一种由定子电压和电流交直轴分量表示的感应电动机复数简化模型;利用端口电流电压暂态量,采用步长加速法进行模型参数辨识。该模型考虑了电动机的非线性,避免了求解复杂的非线性微分方程组,减化了参数辨识过程,保证了算法的收敛性和结果的准确性,提高了辨识的稳定性和效率。在两种电机控制方式下进行算例仿真及参数辨识,验证表明该模型正确有效,参数可辨识且精度高,易于工程实现。     

Rotor resistance identification and stability control method in bearingless induction motor drives

Generally, vector controllers in induction motors tend to suffer from the influence of rotor resistance variation caused by temperature and load torque conditions. Several rotor resistance identification methods have been proposed in the literature. In this paper, a novel rotor resistance identification technique is proposed based on variables in the magnetic suspension control loops. When static force, such as a shaft weight, is applied, force commands are automatically generated in the opposite direction to satisfy the force equilibrium. However, the amplitude and direction of the force command vary in accordance with the rotor resistance variation. Thus, the rotor resistance can be identified from the suspension force command. In addition, influence of temperature drift in gap sensors is investigated. The effectiveness is confirmed experimentally. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(1): 86–97, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20423     

Deadbeat flux level control of direct-field-oriented induction motor

A method for the deadbeat flux level control of a direct-field-oriented induction motor with position control loop has been developed that employs an adaptive rotor flux observer. The observer is a full-order type and is used not only in the direct-field-oriented controller, but also to identify stator and rotor resistances of the motor. The observer reduces the sensitivity of a deadbeat controller to fluctuations in the motor parameters. The main advantage of this method is that it improves the efficiency of an induction motor without sacrificing dynamic performance. This paper describes the method as well as the fundamental characteristics of the system derived from experimental and simulation results.     

双初级耦合直线感应电动机集总参数模型

在动子进行高速大推力运动场合,直线感应电动机可以设计为N(N≥2)台电机初级绕组上下并联布置共用一个次级的结构形式.本文针对N=2的情形,分析了双初级耦合直线感应电动机上下初级绕组边缘气隙磁场耦合和次级涡流路径耦合关系,在此基础上针对双初级耦合直线感应电动机中双初级上下定子单独通电、双初级同时通入同向电流、双初级同时通入反向电流等不同工况,建立了统一的集总参数模型,并进行了耦合参数的辨识.模型计算和小型试验样机实验结果吻合较好,证明了理论分析的正确性.     

Usefulness of a frequency‐hybrid vector control for a sensorless induction motor drive

This paper examines and demonstrates the usefulness of a frequency‐hybrid vector control scheme for sensorless induction motor drive through actual‐machine‐based performance evaluation tests. The new approach utilizes a new indirect orientation scheme and a stable‐filter‐embedded direct orientation scheme, and exploits their advantages. It is confirmed through extensive tests with small and large standard motors such as 0.3, 3.7, 30 kW and special low‐voltage motors dedicated to electric vehicles that the sensorless vector control scheme has the following potential usefulness: (1) it can make machines that produce more than 200% rated torque at standstill, (2) in both motoring and regenerating modes, the rated torque can be produced even in the very slow speed range, including zero speed and zero frequency, (3) for constant speed, good linearity of torque response is attained, (4) it has the ability to track variable speed acceleration commands up to ±5000 rad/s² in the mechanical frequency sense, (5) it can accept a zero‐speed command and settles the machines to a stable standstill with no vibration, (6) it accepts instant injection of rated load even for zero‐speed control, and (7) it accommodates a load with huge inertia. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(4): 44–58, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10073     

Performance improvement of induction motor speed sensor‐less vector control system using an adaptive observer with an estimated flux feedback in low‐speed range

Because of various errors caused by the dead time of an inverter, temperature variation of resistances, and so on, speed estimation error is inevitable in speed sensor‐less vector control of an induction motor. In particular, the speed control loop becomes unstable at near‐zero frequencies. In order to solve these problems, this paper proposes a novel design of an adaptive observer for speed estimation. By adding a feedback loop of the error between the estimated flux and the flux command, the sensitivity of speed estimation and primary resistance identification is improved. The proposed system is analyzed and appropriate feedback gains are derived. Experimental results showed good performance in the low‐speed range. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(3): 33–46, 2009; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20909     

基于扩展卡尔曼滤波的直线感应电机速度观测

为解决在直线感应电机（Linear Induction Motor,LIM）的高性能闭环控制系统中取消速度传感器后,速度闭环缺少反馈环节中的速度信息的问题,在考虑LIM的边端效应前提下,实现了一种基于扩展卡尔曼滤波算法的速度观测器。首先,基于考虑边端效应的三相直线感应电机的数学模型,推导出具有合适增益和协方差更新矩阵的扩展卡尔曼滤波观测器。并基于LIM的矢量控制系统,将观测器辨识的速度参数反馈到速度闭环系统中。然后,在Simulink中搭建带有速度观测器的直线感应电机矢量控制系统模型,对观测器的辨识速度和电机实际速度进行对比。最后,结果表明,利用辨识速度进行闭环控制可以保证系统稳定运行。在三种负载情况下,观测器的预测速度和实际速度之间的误差在0.51%到2.34%之间,对系统多种动态性能进行分析可知,基于扩展卡尔曼滤波观测器的LIM矢量控制系统,随着负载增大,预测速度的误差随之增大,推力误差随之减小,磁链幅值误差随之略微增大。因此,在考虑边端效应的情况下,基于扩展卡尔曼滤波的观测器可以代替速度传感器实现空载和带载时的三相直线感应电机控制。     

Compensation of stator iron loss of vector‐controlled induction motor using robust flux observer

A new vector control system of an induction motor is proposed in this paper to reduce the influence of iron loss, which has been difficult to deal with. Recently, many methods have been proposed to improve the accuracy of torque control, concentrating on the identification of parameters and the adjustment of the controllers. But, it is necessary for experts to tune parameters initially in those methods. The new method can reduce the influence of iron loss by using a robust flux observer. By adding current decoupling control for compensation of the iron loss, a vector control system with high torque linearity can be constructed. © 2001 Scripta Technica, Electr Eng Jpn, 137(3): 59–66, 2001     

基于SVPWM五相感应电机直接转矩控制研究

针对感应电机直接转矩控制(DTC)采用开关表的滞环方法时,存在电流和转矩脉动等问题,提出在DTC中应用空间矢量脉宽调制(SVPWM)的方法。根据五相感应电机模型和DTC基本原理,推导出参考电压矢量。分析了五相逆变器的空间电压矢量,并从中选取出22个有效电压矢量,根据最近四矢量SVPWM算法,计算出第k扇区中工作电压矢量的作用时间。建立了基于双DSP控制的实验系统,实验结果表明,该方法减小了电流和转矩脉动,具有良好的稳态和动态性能。     

异步电机无速度传感器矢量控制系统中扩展卡尔曼滤波器的优化研究

利用扩展卡尔曼滤波器,将转速看成一个状态量,根据定子的电流和电压值估算转速.通过仿真对滤波器初值的选取进行了研究,得到优化的卡尔曼滤波器,试验结果表明,速度估算的准确性高,系统对于电机参数的变化不敏感,具有较强的鲁棒性.