Analysis of field-oriented controlled induction motor drives under sensor faults and an overview of sensorless schemes

To obtain high dynamic performance on induction motor drives (IMD), variable voltage and variable frequency operation has to be performed by measuring speed of rotation and stator currents through sensors and fed back them to the controllers. When the sensors are undergone a fault, the stability of control system, may be designed for an industrial process, is disturbed. This paper studies the negative effects on a 12.5 hp induction motor drives when the field oriented control system is subjected to sensor faults. To illustrate the importance of this study mine hoist load diagram is considered as shaft load of the tested machine. The methods to recover the system from sensor faults are discussed. In addition, the various speed sensorless schemes are reviewed comprehensively.     

MRAS state estimator for speed sensorless ISFOC induction motor drives with Luenberger load torque estimation

This paper presents a novel method for estimating the load torque of a sensorless indirect stator flux oriented controlled (ISFOC) induction motor drive based on the model reference adaptive system (MRAS) scheme. As a matter of fact, this method is meant to inter-connect a speed estimator with the load torque observer. For this purpose, a MRAS has been applied to estimate the rotor speed with tuned load torque in order to obtain a high performance ISFOC induction motor drive. The reference and adjustable models, developed in the stationary stator reference frame, are used in the MRAS scheme in an attempt to estimate the speed of the measured terminal voltages and currents. The load torque is estimated by means of a Luenberger observer defined throughout the mechanical equation. Every observer state matrix depends on the mechanical characteristics of the machine taking into account the vicious friction coefficient and inertia moment. Accordingly, some simulation results are presented to validate the proposed method and to highlight the influence of the variation of the inertia moment and the friction coefficient on the speed and the estimated load torque. The experimental results, concerning to the sensorless speed with a load torque estimation, are elaborated in order to validate the effectiveness of the proposed method. The complete sensorless ISFOC with load torque estimation is successfully implemented in real time using a digital signal processor board DSpace DS1104 for a laboratory 3 kW induction motor.     

Speed sensorless model predictive current control of doubly-fed induction machine drive using model reference adaptive system

This paper presents a speed sensorless control scheme named as finite control set-model predictive current control (FCS-MPCC) using a modified fictitious ohmic quantity (R) based model reference adaptive system (MRAS) for grid-connected doubly-fed induction machine (DFIM) drive. The variables of the reference model of this speed sensorless scheme (R-MRAS) are represented in stationary reference frame while those for the adaptive model are denoted in synchronously rotating reference frame. The sensorless formulation thus obtained is completely independent of any stator/rotor resistance terms. The scheme is also devoid of any stator/rotor flux estimation. Moreover, the intuitiveness of FCS-MPCC brings in additional flexibility in comparison to the conventional control techniques like field oriented control (FOC) and direct torque control (DTC). The overall scheme demonstrates faster execution time than FOC/DTC based control of DFIM drive. The proposed control algorithm is simulated and tested for limited speed range application in MATLAB/Simulink. The validation of simulation results are further done by experimentation on a dSPACE-1103 based DFIM laboratory setup.     

基于空间矢量无速度传感器感应电机的直接转矩控制

直接转矩控制(DTC)对于异步电机而言，它能产生快速及好的鲁棒性响应。介绍了一种新的对于无速度感应电动机基于空间矢量(SVM)模型的直接转矩和磁链控制，它能降低稳态时力矩、磁链和速度的波动，在全速度范围无速度传感应用中将产生更好的稳态性能的同时保留DTC的暂态优点。仿真结果显示，该方法有着比传统的DTC更好的性能。     

基于MRAS的低速永磁电机的无位置传感器控制

为解决低速复式永磁同步电机(PMSM)在工作环境下的稳定运行等问题,将基于模型参考自适应法(MRAS)的无位置传感器控制方法应用到电机的控制策略中.在控制系统中,根据电机的参考模型,建立了可调模型,基于合适的自适应规律进行调节,估算出了电机的转速和转子位置角;在Simulink环境下建立了基于模型参考自适应的无位置传感器控制仿真模型,并进行了仿真与分析.研究结果表明,该模型参考自适应法估算精度较高,稳态转速平稳且跟踪性能好,动静态性能较好,对电机给定转速和负载扰动的鲁棒性强,适应性好;但同时该方法对电机的参数很敏感.     

Implementation of a sliding-mode-based position sensorless drive for high-speed micro permanent-magnet synchronous motors

Due to issues such as limited space, it is difficult if it is not impossible to employ a position sensor in the drive control of high-speed micro PMSMs. In order to alleviate this problem, this paper analyzes and implements a simple and robust position sensorless field-oriented control method of high-speed micro PMSMs based on the sliding-mode observer. In particular, the angular position and velocity of the rotor of the high-speed micro PMSM are estimated using the sliding-mode observer. This observer is able to accurately estimate rotor position in the low speed region and guarantee fast convergence of the observer in the high speed region. The proposed position sensorless control method is suitable for electric dental handpiece motor drives where a wide speed range operation is essential. The proposed sensorless FOC method is implemented using a cost-effective 16-bit microcontroller and tested in a prototype electric dental handpiece motor. Several experiments are performed to verify the effectiveness of the proposed method.     

基于MRAS的无位置传感器永磁同步电村控制技术的研究

以永磁同步电动机的电磁关系为参考,建立了以角频率为可调参数的电流模型,并推导了基于Popov超稳定性定理的自适应率．从而提出了一种基于模型参考自适应系统MRAS（model reference adaptive system）的磁同步电动机无位置传感器控制方法。通过构建该调速系统基于Matlab／Simulink的仿真分析模型,进行了控制策略的仿真验证。分析结果表明,该控制方法具有较高的速度辨识精度,较好的稳态、动态性能和抗负载扰动能力。     

基于SMO的开关磁阻电机无位置传感器控制仿真研究

针对开关磁阻电机中位置传感器的引入用所带来的结构复杂程度以及系统的成本的提高、电机可靠性以及坚固性降低等问题,提出了一种新的基于滑模观测器的开关磁阻电机无位置传感器控制方法:采用五点法磁链模型,结合滑模观测器实现了转子位置无位置传感器控制。该方法以转速以及电机转子位置作为状态变量,以实际磁链以及估算磁链的偏差作为滑模面,构建出了滑模观测器,对转子位置进行了间接检测。然后利用Matlab仿真软件搭建出了12/8极开关磁阻电机的仿真模型,并在Simulink环境下对开关磁阻电机进行了仿真研究。研究结果表明,所给出的无位置传感器控制方法可以有效地估算出电机的转速以及转子的位置,测量得到的转子位置误差小,具有较好的鲁棒性以及抗干扰能力,动态性能较好。     

无速度传感器转子磁场定向感应电机控制系统研究与开发

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了扩展卡尔曼滤波对磁链和电机转速的估算，并成功应用此算法设计了一套DSP实验控制系统，实现了速度自适应识别。介绍了DSP实验系统的硬件和软件实现方法并对实验结果进行了分析。模型试验应用于1．0kW的感应电机取得了较好的的控制效果。     

数控机床主轴驱动的变频控制

介绍了采用数控车床的主轴驱动中,变频控制的系统结构与运行模式,并简述了无速度传感器的矢量变频器的基本应用。     

Design and performance analysis of an iterative flux sliding-mode observer for the sensorless control of PMSM drives

To improve the performance of permanent magnet synchronous motor (PMSM) drives, a sensorless control scheme based on a novel iterative flux sliding-mode observer (IFSMO) is proposed in this paper. Two major drawbacks of the conventional sliding-mode observer (SMO), namely, chattering phenomena and high-order harmonics, are discussed. These drawbacks affect the estimation accuracy of the SMO and reduce the control reliability of the system. To eliminate high-order harmonics, a flux SMO is designed by expanding the PMSM state equations with the PM flux. The flux SMO estimates the rotor speed and position using the flux linkage instead of back-EMF information. Moreover, to reduce the chattering in the estimation results, the proposed flux SMO is iteratively used in one current sampling period to adaptively adjust the observer gain. An overall PMSM sensorless control system based on the proposed IFSMO is designed, and an experimental platform using the TMS320F28335 digital signal processor (DSP) controller is built. The superior chattering reduction and harmonic suppression characteristics of the proposed IFSMO are experimentally validated, and the experimental results verify the feasibility of using the proposed IFSMO-based PMSM sensorless scheme in practical applications.     

基于全速域混合控制的同步磁阻电机无传感器矢量控制系统

针织大圆机的特殊运动状态要求其驱动电机具有较大的启动和带载能力以及较高的稳态运行精度,同步磁阻电机是一种应用于针织大圆机的理想电机,但现有同步磁阻电机无传感器控制,存在转子位置估计误差大、速度切换不平滑等问题。对此,提出一种基于全速域混合控制的同步磁阻电机无传感器矢量控制系统,零速和低速时采用脉振高频电流注入法,通过在估计坐标系的d轴注入一个幅值恰当的高频电流信号,使用估计q轴的高频电压信号估计转子位置;中速和高速时采用模型参考自适应法,通过建立数学模型并对其进行稳定性分析来估计转子位置;为了实现零速和低速到中高速的速度切换,提出一种改进的过渡区域融合观测方案,采用正弦型饱和函数代替传统的线性切换函数进行位置融合。为了验证方案的有效性,搭建了平台进行测试。由结果表明,该方案启动过程带载能力强,切换过程平滑且稳定,稳态运行过程波动小,是一种较适合大圆机电机驱动的无传感器矢量控制方法。     

Sensorless passivity based control for induction motor via an adaptive observer

The work of this paper addresses the study and application of control strategies based on the passivity of a sensorless induction motor (IM) in order to guarantee a high performance operation and to increase reliability at a lower cost. This control approach based on the passivity or the energy formulation is generally simple and physically meaningful. It achieves the control objective by reshaping the system natural energy and then injecting a damping term. A full-order adaptive observer is also considered to estimate the IM rotor flux and mechanical speed. These estimated quantities are then used in the control scheme. The observer gain is synthesized in the way that it minimizes the instability zone in the regenerative mode to a line in the torque–speed plane. The control-observer set is tested on the trajectories of the various operating modes (motor mode, regenerating mode and low speed mode).     

Fuzzy sliding mode observer with dual SOGI-FLL in sensorless control of PMSM drives

To improve the performance of permanent-magnet synchronous motor (PMSM) drives, a sensorless control scheme based on a sliding mode observer (SMO) with a fuzzy logic controller (FLC) and a dual second-order generalized integrator-frequency locked loop (DSOGI-FLL) is proposed in this paper. The major drawbacks of the conventional SMO, namely chattering phenomena, high-order harmonics and external noise, are discussed. These drawbacks affect the estimated accuracy of the SMO and reduce the control reliability of the system. To eliminate these drawbacks, an FLC is designed and integrated into the SMO to adjust the observer gain in a self-adaptive manner and to reduce the chattering; an existing dual synchronous frequency extract filter-phase locked loop (DSFF-PLL) is used to filter out the main components of high-order harmonics and to calculate the rotor position and speed precisely. Furthermore, to obtain an accurate fundamental frequency for the phase locked loop (PLL) and filter out the remaining harmonics and external noise signals, DSOGI-FLL processing is developed and incorporated into the DSFF-PLL. An overall PMSM sensorless control system based on the proposed SMO is designed, and an experimental platform using the TMS320F28335 DSP controller is built. Comparative experiments using the proposed SMO and the conventional SMO are performed to validate the effectiveness of the proposed FLC and the DSFF-DSOGI-FLL-PLL structures. Performance experiments of the overall proposed SMO-based sensorless control scheme are performed to verify the robustness and control reliability of the system. The results show that the proposed SMO has satisfactory performances and can be used in practical engineering.     

基于单片机平稳运行的无刷直流电机无传感器控制系统设计

设计了一套无传感器的无刷直流电机PWM闭环调速的系统,该系统基于8位单片机STC12C5A60S2和TB6537控制芯片,通过反电动势与端电压相结合的反馈电路和相应的软件补偿的方法减小电机在有负载变化等干扰因素下的速度波动,实现无传感器的无刷直流电机的平稳运行。试验证明,系统可以实现很好的调速控制,减少外界干扰对电机速度的干扰,而且成本低。     

基于能量函数的永磁同步电机无速度传感器H∞控制

研究了基于能量函数的永磁同步电机无速度传感器H_∞控制问题。为有效控制电机转速,首先对无扰动条件下的永磁同步电机哈密顿模型进行整形,使转速达到期望值。然后,在存在扰动的条件下,设计了一种基于哈密顿函数的H_∞控制器。最后,采用基于哈密顿函数的扩张+反馈方法设计了一种观测器,对转子角速度进行测量,实现了无速度传感器整形+H_∞控制。仿真结果表明,基于观测器的整形+H_∞控制器能实现对角速度的高精度估计,可有效克服扰动,并较好地实现了对电机转速的控制功能。     

基于参数预标定的长行程PMLSM无传感器控制

为了解决长行程定子不连续永磁直线同步电机存在的因无法全程安装位置传感器和不同动子和定子之间的电磁参数不固定所造成的控制性能下降的难题,提出一种在每一段定子内先进行参数标定,再进行速度控制的控制系统设计。首先,在动子进入过程中,对电机进行电磁参数标定,根据标定参数对控制器参数进行调整,以达到更好的控制效果。然后,使用无位置传感器控制系统使动子快速达到设定速度值并稳定运行。实验结果表明:动子进入过程参数标定精度分别为0.002Wb和0.000 4H;无位置传感器控制中位置估计精度为0.63mm,速度收敛时间为0.45s,稳态误差为0.02m/s。基本满足永磁直线同步电机用于长行程运输的控制快速性、稳定性等要求。     

Friction coefficient, torque estimation, smooth shift control law for an automatic power transmission

For shift quality improvement, torque sensors are currently too expensive to be used on production vehicles. To achieve smooth acceleration shift, the reference trajectory of the clutch slip speed for accomplishing the shift process within a designated shift completion time and its relationship with the clutch actuating torque were suggested by Jeong and Lee (1999). In order to facilitate the proposed algorithm, nonlinear estimators for necessary information such as the axle shaft torque, clutch friction and turbine torque were designed using only speed sensors. Accounting for the modeling error, a control law for this indirect smooth shift was proposed based on the above mentioned suggestions. Simulation results of the proposed estimators and shift controller were presented and further considerations for practical applications are discussed.     

一种新型的基于观测器的感应电动机转速识别方法

在无速度传感器感应电动机控制系统的转速估算观测器中,要求有一个合适的电流反馈增益来保证转速估算的稳定性与工作性能.新设计了一个观测器的电流反馈增益,以实现在整个工作范围特别是低速、反向发电范围,转速估算的稳定工作.对系统进行了,仿真结果表明,系统具有较好的性能.     

3 MW永磁直驱风电变流器设计与仿真

系统阐述3 MW直驱风电变流器设计的各个环节。重点介绍如何将无速度传感器控制技术运用到风电变流器设计中,从根本上解决速度传感器带来的故障问题。同时在α-β坐标系中实现电流闭环控制,加入载波移相和DPWM1控制理论,降低制造成本。