Experimental verification for stability improvement of sensorless vector control system of induction motor using real‐time tuning of observer gain

This paper proposes a method for the design of the adaptive rotor flux observer gain to improve stability at low speed and in regenerating mode. The method is based on stability analysis, which utilizes a linearized model considering all systems, including each control loop. Therefore, the proposed method considers the effects of motor constants and control circuit constants. The stability analysis using the transfer function for the rotor speed considers the arrangement of poles and zeros and the steady‐state error. The rotor flux observer gain which improves the stability for each operating condition is ascertained. This paper also proposes a real‐time tuning method for the observer gain. The validity of the proposed method was confirmed by simulation using Matlab Simulink and by experiment. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 67–81, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20715     

Lower speed range drive for sensorless vector controlled induction machines with stator voltage offset compensation method

The vector control method is widely used for induction machine drives. Recently, sensorless vector control for induction machines has been investigated and proposed. The speed range for the drives is limited to about 1:100 in industry. The main reason for this limitation is the inaccuracy of stator voltage measurement. The lower the rotor speed is, the lower the stator voltage. Therefore, it is difficult to detect the stator voltage accurately in the lower speed region, and difficult to control motor speed and motor torque precisely. This paper presents a method of improving the lower speed performance of sensorless vector controlled induction machine drives using offset compensation of stator voltage. The offset is compensated by using the fluctuation of the estimated rotor flux. The validity of the proposed method is verified by experimentation. © 2000 Scripta Technica, Electr Eng Jpn, 133(1): 79–86, 2000     

一种用于异步电机无速度传感器控制的自适应滑模观测器

针对异步电机无速度传感器中存在的对参数变化鲁棒性差的问题,研究了一种基于自适应滑模观测器的异步电机无速度传感器的矢量控制方案。自适应滑模观测器根据电机静止坐标系下的数学模型构造了转子磁链观测器,定子电流观测值与实际值的误差构成观测器的滑模面,在滑模运动下该观测器的观测值最终趋近于实际值,从而实现转子磁链的估计。电机转速由自适应方法估算得到,滑模观测器的稳定性可由李雅普诺夫稳定性证明。与其他方案相比,该方法的优点在于实现简单,对参数变化具有鲁棒性。仿真和实验对控制方案的正确性和可行性给出了验证,该观测器可以实现对转子磁链和转速的观测,且在负载扰动和给定转速变化的情况下该滑模观测器具有鲁棒性。     

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.     

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。     

转子磁场定向速度自适应估算感应电机控制系统的研究

介绍了一种采用磁链和开环速度估算器的转子磁场定向的控制系统,系统设计的关键问题是磁链的观测和速度的准确估算。按照模型参考自适应系统构造出参考模型和可调模型来实现电机转速的估算,并对三相交流感应电机的磁链观测和速度估算进行了推导,求出了磁链观测和速度估算的数学公式,在实验系统中实现了扩展卡尔曼滤波对磁链和转速的估计,并成功设计了一种速度自适应识别方法,采用开环速度估算器实现了无速度传感器的系统速度估算。系统模型试验采用DSP处理器(TMS320LF2407)应用于1.0kW的感应电机。     

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。     

Design of an adaptive observer for sensorless vector control of induction machines under regenerating conditions

The objective of this investigation is to stabilize a sensorless vector control system of induction motors by means of an adaptive observer in regenerating mode at very low speed. The adaptive observer gain is designed by means of the Routh–Hurwitz criterion. It is verified by simulation and experiment that the proposed system is stable. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(4): 78–87, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10202     

MRAS-based speed sensorless control scheme with stator resistance identification function for vector-controlled induction motor drives

This paper describes a new scheme for the speed sensorless control of the vector-controlled induction motor drive. Based on the model reference adaptive system (MRAS) theory, the rotor speed of the induction machine is estimated with a full-order adaptive observer. The estimated speed then is used as the signal for the vector control and the speed control. To accurately estimate the speed at the lower speed range, the value of the stator resistance also is identified at the same time and then is used to modify the resistance value set in the observer. The resulting system is verified to be hyperstable with Popov's criterion. As a result, this drive can operate stably in a wide range of speed even at zero speed. Also, it is shown theoretically that neither speed nor resistance of the rotor can be identified at the same time because these two parameters are dependent on each other. Simulation results and experiments also show that the scheme is effective.     

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     

感应电机无速度传感器控制自适应速度观测器

理论与实践证明自适应速度观测器是实现高性能的感应电动机无速度传感器控制系统的有效方法之一。由于该系统的非线性性质,在观测器设计以及系统应用中还有许多有待解决的问题。针对此类问题,从理论联系实际的角度,分析现有的电机磁链、速度观测器理论的要点及其成果,如建模的条件、自适应速度估计算法及其物理性质、系统稳定性分析、线性化方法、以及观测器参数的辨识等。同时,给出了实验结果、指出了这些内容中尚存的相关问题。     

Adaptive control for speed‐sensorless induction motors with uncertain load torque and rotor resistance

The problem of controlling a speed‐sensorless induction motor is addressed. Smooth reference signals for rotor speed and flux modulus are required to be tracked for any unknown constant values of load torque and rotor resistance within known bounds. A fourth order non‐linear adaptive tracking control is presented which is based on a novel rotor speed observer and on two identifiers for the uncertain parameters; it guarantees asymptotic rotor speed tracking and exponential rotor flux modulus tracking with an explicitly computed domain of attraction. The closed‐loop performances are illustrated by simulation. Copyright © 2005 John Wiley & Sons, Ltd.     

带有转子电阻补偿的异步电机电流型磁链观测器

提出了一种改进的异步电机转子磁链电流型观测器。造成电流型观测器估计误差的转子电阻不确定项,在定子电流方程中同样存在。把它扩张成新的状态变量后,根据扩张状态观测器(ESO)的原理,在电流、转速可测的条件下可以对其进行观测。把所得的对不确定项的估计值引入电流型观测器,则可以消除转子电阻的影响。与传统观测器的仿真对比结果表明,该方法对转子电阻的变化具有很强的鲁棒性。     

Online tuning method of stator and rotor resistances in both motoring and regenerating operations for vector‐controlled induction machines

The vector control of induction motors is widely used. This method needs accurate motor parameter but the stator and rotor resistance vary due to motor temperature variation. If the value of resistance in the controller can be set up accurately at first, there must be a difference between the reference and real value of torque because of drift of the resistance. It is necessary to adapt the resistance value. The indirect field‐oriented control of an induction motor requires the value of rotor resistance only, but the direct field‐oriented control method with rotor flux observer requires the value of not only rotor resistance but also stator resistance in the controller. Consequently, it is necessary to adapt both stator resistance and rotor resistance. A parameter adaptation scheme has previously been proposed for the direct field‐oriented control method with rotor flux observer, but this method cannot be used when the motor is in regenerating operation. In this paper, a new stator and rotor resistance adaptation scheme is proposed, which can be applied when the motor is in regenerating operation. The usefulness of the proposed adaptation scheme is confirmed by simulation. © 2001 Scripta Technica, Electr Eng Jpn, 135(1): 56–64, 2001     

A nonlinear tracking control for sensorless induction motors with uncertain load torque

We propose a novel nonlinear tracking control algorithm for induction motors with uncertain load torque in which only stator currents are used for feedback: rotor speed and flux sensors are not required; no open‐loop integration of flux dynamics is used. For a class of reference signals, for sufficiently small computable time‐varying load torque uncertainty and for any initial condition belonging to an explicitly computed region, closed‐loop boundedness is guaranteed while, under persistency of excitation, local exponential rotor speed and flux modulus tracking are achieved in the case of constant load torque. Copyright © 2007 John Wiley & Sons, Ltd.     

引入比例谐振调节器的双馈电机转子电流无速度传感器控制

双馈风力发电机转子电流模型参考自适应系统(MRAS)的转速估算方法中,由于定、转子电压、电流采样信号的漂移及AD转换的偏差,致使所估计的双馈电机转速幅值中呈现不同程度的交流脉动。针对此问题,提出了在自适应实时调节机构中,采用PI并联比例谐振(PR)控制器共同作用的控制策略。该方法可消除转速估计中角频率和转差频率的交流脉动,实现转速精确估计,提高双馈电机发电质量。基于10 k W的双馈风力发电模拟平台进行了实验研究,通过与PI控制对比验证了PI并联比例谐振控制的优越性。     

一种异步电机无速度传感器间接磁场定向控制策略

针对无速度传感器异步电机,提出了一种新的滑模磁通和速度观测方法。实际电流和观测电流之间的误差收敛到零,保证磁通观测器的精确性。根据估计的定子电流和转子磁链来估计转子的转速和转子时间常数。估计的转子时间常数用于滑模计算和观测器结构中,估计的转速用来作为转速调节的反馈。仿真结果证明所提出的速度估算方法有效以及所提出的观测器结构具有鲁棒性。     

基于新型全阶观测器的感应电机无速度传感器控制

随着我国海上风电的迅猛发展,感应电机作为一种主流电机已广泛用作海上风电中的发电机组.针对感应电机无速度传感器控制中转速估算误差大、过渡不平滑及反馈矩阵的计算量大等问题,设计了一种基于简化型反馈矩阵的新型全阶观测器方案.设计时先按照极点平移法推导出反馈矩阵中各元素的表达式,再从稳定性与收敛速度两方面综合考虑,提出一种反馈...     

SMO在无位置传感器PMSM驱动控制系统的应用

为了开发一种成本低、可靠性好、维护简单的无位置和速度传感器的控制方法,在分析永磁同步电动机PMSM的数学模型和滑模变结构控制基本理论的基础上,建立了基于滑模观测器SMO的PMSM无传感器驱动控制系统模型.以TMS320LF2407A DSP为核心构建了PMSM无传感器驱动控制系统,并进行了仿真和实验研究.结果表明,所提出滑模观测器能够准确地估算出电机的位置信息,并且系统具有较好的静、动态特性,从而验证了滑模观测器在无位置传感器PMSM驱动控制系统中应用的可行性和正确性.