Adaptive interconnected observer-based backstepping control design for sensorless induction motor

In this paper, an observer-based controller scheme is designed to robustly drive a sensorless Induction Motor (IM) even for the case of low frequencies with unknown load torque. Combining the field oriented control strategy with the backstepping control method, we introduce additional integral terms to improve the robustness properties of the controller in spite of uncertainties and perturbations. The estimation of the fluxes, the speed, the load torque and moreover the stator resistance is given by an adaptive interconnected observer. The practical stability of the proposed observer–controller scheme is proved. Finally, some experimental test results are given on the framework of a specific sensorless induction motor benchmark.     

An asymptotically stable sensorless speed controller for non‐salient permanent magnet synchronous motors

A solution to the longstanding problem of sensorless control of an electrical machine is provided in this paper. That is, the construction of an asymptotically stable controller that regulates the mechanical speed of the motor, measuring only the electrical coordinates. The result is presented for a non‐salient permanent magnet synchronous motor perturbed by an unknown constant load torque. The proposed scheme is a fourth order nonlinear observer‐based controller that does not rely on—intrinsically nonrobust—operations like open‐loop integration of the systems dynamical model nor signal differentiation and can be easily implemented in real time. The controller is easy to commission, with the tuning gains directly determining the convergence rates of the position, speed, and load torque observers. Simulation and experimental results are presented. In particular, a comparison with a sensorless field‐oriented controller, recently proposed in the drives literature, is carried out. Copyright © 2012 John Wiley & Sons, Ltd.     

Experimental sensorless control for IPMSM by using integral backstepping strategy and adaptive high gain observer

In this paper a robust sensorless control for an Interior Permanent Magnet Synchronous Motor (IPMSM) is designed. The proposed control strategy uses a backstepping controller, whose robustness is improved by using integral actions added at each step of the original algorithm, and by a Maximum-Torque-Per-Ampere strategy (MTPA) to improve its energy efficient operation. Furthermore, to implement this controller in the framework of the mechanical sensorless control from the only measurements of the currents and voltages, an adaptive interconnected high gain observer is developed for estimating the rotor speed, the position and the load torque. Moreover, sufficient conditions are given to ensure the practical stability of the Observer-Controller system even if bounded uncertainties occur. Finally, the performance and the effectiveness of the designed method are tested experimentally throw a significant benchmark including different speed references and with significant robustness tests. A comparative evaluation of the computational effort of our scheme with respect to classical motor control is given.     

Speed-assigned Position Tracking Control of SRM With Adaptive Backstepping Control

A novel speed-assigned method is applied to the position tracking control of switched reluctance motor (SRM). A speed control freedom can be drawn into the position control through speed assignment. Adaptive backstepping control is used to design the position controller for the SRM. The accuracy of position tracking of the SRM can be enhanced with speed assignment. A disturbance observer is further designed to enhance the estimation accuracy of the unknown load torque. Simulation results certify that the design scheme is right and effective.      

基于扰动观测器的PMSM同步协调滑模控制

针对在负载扰动情况下多永磁同步电机控制系统出现电机转速不同步的问题,提出了基于扰动观测器的永磁同步电机同步协调滑模控制策略。从单电机高性能控制策略和三电机耦合结构角度出发,首先,在矢量控制基础框架下,设计了基于非线性负载转矩观测器的积分型滑模速度控制器,构成了单电机高性能矢量控制调速系统;其次,提出了一种基于PI速度补偿器的偏差耦合控制结构,相比传统的偏差耦合控制结构能较好地实现在负载扰动下三电机的转速同步协调运行。最后通过仿真验证了方法的有效性。     

An extended observer-based robust nonlinear speed sensorless controller for a PMSM

This work focuses on the problem of observer-based robust speed sensorless control of a 3-phase permanent magnet synchronous motor (PMSM). Nonlinear design techniques are employed for designing robust speed controller and observer that are able to withstand the effects of modelling uncertainties and load variations. A new cascaded observer scheme is proposed comprising a continuous sliding mode observer (SMO) and an extended high-gain observer (EHGO). The proposed cascaded observer reduces chattering, exhibits reasonable insensitivity to modelling inaccuracies and is capable of withstanding errors due to the finite boundary layer of continuous SMO. For the robust speed control, an integral sliding mode controller is designed that yields fast and accurate speed tracking performance even in the presence of bounded uncertainties and external disturbances. The complete scheme has been evaluated using simulations and experiments.     

A robust sensorless output feedback controller of the induction motor drives: new design and experimental validation

In this article, a sensorless output feedback controller is designed in order to drive the induction motor (IM) without the use of flux and speed sensors. First, an observer that uses only the measured stator currents is synthesised to estimate the mechanical variables (speed and load torque) and the magnetic variables (fluxes) by structurally taking into account the unobservability phenomena of the sensorless IM (SIM) and the parametric uncertainties. Second, a current-based field-oriented sliding mode control that uses the flux and the speed estimates given by the former observer is developed so as to steer the estimated speed and flux magnitude to the desired references. Since the observer error dynamic is independent from the known input control and depends on the IM parametric uncertainties, a kind of separation principle is introduced to guarantee the practical stability of the whole closed-loop system ‘observer–controller’ (‘O-C’) according to observability and unobservability time variation. A significant benchmark taking into account the unobservability phenomena of the SIM is presented to show the performances of the whole control scheme against experimental set-up.     

基于线性自抗扰的开关磁阻电机调速控制研究

开关磁阻电机调速系统是复杂的非线性时变系统,负载扰动大,变量之间耦合严重,针对上述系统的性能特点提出采用线性自抗扰控制策略对系统进行控制的方法。首先为克服负载扰动变化,电机磁链呈非线性以及电流、位置等参数耦合的内外部干扰问题,设计扩张状态观测器对系统内扰和外扰进行准确估计并实时补偿。然后设计PD（比例-微分）控制器抑制系统给定与扩张状态观测器反馈的观测对象状态变量之间的跟踪误差。最后在仿真平台上对设计的控制系统进行试验并与传统PID控制方案进行对比,结果显示,对于给定的阶跃信号线性自抗扰控制器只需0.09s即可达到稳态且无超调,而PID控制器需要3s才能实现稳定跟踪。因此相比于传统PID控制,线性自抗扰控制器拥有更优的动静态性能,并且系统在外部负载扰动和内部模型参数变化的情况下也有良好的控制效果,表现出了很好的鲁棒特性。     

High-order sliding mode observers and integral backstepping sensorless control of IPMS motor

This paper presents a robust high-order sliding mode interconnected observer and an integral backstepping controller for a sensorless interior permanent magnet synchronous motor. To limit the chattering phenomenon on the observed state, a super twisting algorithm is combined with an interconnected observer to design a new high-order sliding mode observer which will be used for multiple-input multiple-output systems. The proposed observer is used to estimate in finite time the rotor position, the speed and the stator resistance. Moreover, a robust nonlinear controller based on the backstepping algorithm is designed where integral actions are introduced step by step. This controller allows to track a desired reference which is computed by using a maximum-torque-per-ampere strategy. Simulation results are shown to illustrate the performance of the proposed scheme by using significant trajectories including the zero speed and under parametric uncertainties.     

Synchronization and Tracking Control for Dual‐motor Driving Servo Systems with Friction Compensation

A nonsingular fast terminal sliding mode (NFTSM) controller is designed by incorporating the variable gain neural network (NN) observer, which is utilized to guarantee motor speed synchronization and load position tracking of dual‐motor driving servo systems. By designing the variable gain NN observer, the states and uncertain nonlinearities of servo systems are estimated with fast convergence rate and small steady‐state error, where the effects from external disturbance are suppressed as well. Based on the estimated states, the cross‐coupling synchronization strategy and NFTSM tracking scheme are designed to achieve the rapid speed synchronization and precise load tracking, where the NNs are introduced to approximate and compensate friction nonlinearities. In particular, a novel nonlinear synchronization factor characterizing the degree of speed synchronization is proposed to achieve switching between synchronization control and tracking control, which is proven to deal with the coupling problem of synchronization and tracking. Finally, the comparative simulations and experiments are included to verify the reliability and effectiveness.     

Sensorless fault tolerant control for induction motors

In this paper, a sensorless fault tolerant controller for induction motors is developed. In the proposed approach, a robust controller based on backstepping strategy is designed in order to compensate for both the load torque disturbance and the rotor resistance variation caused by the broken rotor bars faults. The proposed approach needs neither fault detection and isolation schemes nor controller re-design. Moreover, to avoid the use of speed and flux sensors, a second order sliding mode observer is introduced to estimate the flux and the speed. The observer converges in a finite time and leads to good estimates of the flux and the speed even in the presence of the rotor resistance variation and the load torque disturbance. Since the observer converges in the finite time, the stability of the closed-loop system (controller with observer) is shown in two steps. First, the boundedness of the closed-loop system trajectories before the convergence of the observer is proved. Second, the convergence of the closed-loop system trajectories is proved after the convergence of the observer. To highlight the efficiency and applicability of the proposed control scheme, simulation and experimental results are conducted for a 1.5 kW induction motor.     

交流伺服电机速度与位置环的一体化鲁棒控制

提出一种交流伺服系统的离散域复合控制方案,可实现在未知负载条件下的准确位置控制。基于永磁同步电机伺服系统中位置与速度环组成的数学模型,以电机转角位置作为系统的测量反馈信号,设计一个降阶线性扩展状态观测器对电机转速（未量测）和未知负载扰动加以估计,并用于反馈控制和扰动补偿。采用TMS320F2812DSP在一台实际的永磁同步电机上进行了实验测试,结果表明伺服系统能在未知负载情况下实现平稳和准确的目标位置跟踪,且对负载和参数差异具有较好的鲁棒性。这种控制方案可方便地应用于相关的伺服系统。     

无位置传感器的永磁同步电动机反演控制

设计了一种基于无位置传感器的永磁同步电动机(PMSM)反演控制器.该控制器包括基于定子电流检测的速度观测器与反演速度控制器.速度观测器代替位置传感器实现转速的在线估计;反演控制器的设计确保速度控制系统具有快速的转速跟踪与转矩响应.通过设计全局Lyapunov函数保证了控制系统的稳定性.仿真和试验结果表明:基于速度观测器...     

非平衡负载下轮式移动机器人的抗扰PID控制

在非平衡负载条件下,轮式移动机器人(WMR)的前进、转向速度耦合,影响着轨迹跟踪和避障等运动控制性能.为此,本文提出了一种基于抗扰PID(DR–PID)控制器的WMR速度调节主动抗扰(ADR)控制策略.首先,建立WMR的速度耦合模型,引入解耦矩阵减小静态耦合作用;然后,基于一类改进干扰观测器(DOB)控制方法,设计一种具有ADR能力的PID控制器,即DR–PID,用于WMR的速度分散调节.进一步,考虑高频增益不匹配/不确定性,分析闭环系统稳定性条件.所得结论揭示了PID控制器的抗扰机理;最后,在不平衡负载条件下开展WMR运动控制实验研究,实验结果验证了所提方法的有效性.     

A Terminal Sliding Mode Observer Based Robust Backstepping Sensorless Speed Control for Interior Permanent Magnet Synchronous Motor

To achieve high-performance sensorless speed control for the interior permanent magnet synchronous motor (IPMSM) drive system, a terminal sliding mode observer based robust backstepping control is proposed in this paper. Firstly, an integral-type terminal sliding mode observer is designed to replace the real mechanical sensor to obtain the rotor position and speed information. Stability of the observer is guaranteed. Then, a robust backstepping controller with integral and sliding mode actions is designed to achieve speed regulation despite uncertainties and disturbances. The convergence for the backstepping control system is ensured. Finally, the sufficient conditions for input-to-state stability (ISS) property of the observer-controller closed-loop system are also analyzed. Simulation and comparison results have demonstrated the effectiveness of the proposed sensorless control scheme.     

基于混合滑模控制器和反正切观测器的SPMSM直接转矩控制

针对基于传统PI控制的表贴式永磁同步电机(SPMSM)直接转矩控制系统抖振和相位延迟等问题,在转速环节设计新型趋近律,采用模糊自适应方法,实现趋近律参数的动态调节,并通过Lyapunov方法证明稳定性.利用super-twisting滑模策略生成参考电压矢量,完成混合滑模控制器的设计,建立基于反正切函数的滑模观测器,并对转子位置进行合理补偿.仿真实验表明,与PI控制、基于指数趋近律的滑模控制器相比,所设计的控制器在电机空载起动和外加干扰情况下均能有效提高系统响应,显著降低抖振,与其他模型参考自适应观测器相比,所设计观测器能有效减小相位延迟,转子位置辨识结果更准确.     

A Robust Backstepping Sensorless Control for Interior Permanent Magnet Synchronous Motor Using a Super‐Twisting Based Torque Observer

In order to achieve high‐performance speed regulation for sensorless interior permanent magnet synchronous motors (IPMSMS), a robust backstepping sensorless control is presented in this paper. Firstly, instead of a real mechanical sensor, a robust terminal sliding mode observer is used to provide the rotor position. Then, a new super‐twisting algorithm (STA) based observer is designed to obtain estimates of load torque and speed. The proposed observer ensures finite‐time convergence, maintains robust to uncertainties, and eliminates the common assumption of constant or piece‐wise constant load torque. Finally, a sensorless scheme is designed to realize speed control despite parameter uncertainties, by combining the robust backstepping control with sliding mode actions and the presented sliding mode observers. The stability of the observer and controller are verified by using Lyapunov's second method to determine the design gains. Simulation results show the effectiveness of the proposed approach.     

模糊滑模控制和负载转矩补偿的异步电动机直接转矩控制

针对异步电动机(IM)转矩脉动以及抗干扰能力差的问题,设计了基于模糊滑模控制(FSMC)与负载转矩补偿的新型直接转矩控制(DTC),取代传统PID速度调节器的是一种滑模控制器.为解决滑模控制器中负载转矩脉动的问题,用模糊逻辑控制器取代了传统滑模控制律中的不连续部分,可以明显降低异步电动机在低速运转时的转矩脉动.提出了一种负载转矩观测器来估计未知的负载转矩.负载转矩观测器用来估计负载转矩扰动,估计作为速度环的前馈补偿.仿真结果表明:在低速负载转矩扰动时,该设计具有更好的动态响应和速度性能、更高鲁棒性和更强的抗干扰能力.     

级联式滑模观测器的永磁同步电机鲁棒滑模控制

提出了一种基于无速度传感器运行的永磁同步电机非线性控制方法。针对电机速度和位置观测,设计了一种新颖的级联式滑模观测器,解决了传统滑模观测采用低通滤波器的相位延迟问题。前级电流滑模观测器得到反电动势,后级反电动势滑模观测器获取转速和位置信息,利用李亚普诺夫理论进行了稳定性分析。针对速度控制,提出了带扩张状态观测器的滑模速度控制器取代PI调节器,提高了系统的鲁棒性。在滑模观测和控制中均利用双曲正切函数取代符号函数,削弱了系统抖振。将上述方法应用到永磁同步电机矢量控制系统中,通过仿真验证方法的有效性。     

基于LPV观测器的永磁同步电机反推控制

针对永磁同步电机(Permanent Magnet Synchronous Motor,PMSM)无速度传感器转速跟踪控制精度问题,提出了一种基于线性变参数(Lineeo Parameteo Varying,LPV)转速观测器的永磁同步电机反推控制方法。该方法首先根据PMSM的LPV模型,推导出电机的凸胞形顶点方程;然后利用Lyapunov稳定性理论,获得了基于线性矩阵不等式(Lineeo Matrix Inequality,LMI)的观测器设计方法,构造了PMSM的LPV观测器,实现对电机转速及定子交轴电流的重构;最后运用反推控制策略,设计电机闭环系统控制器,实现对电机转速的高精度跟踪控制。仿真结果表明,该方法相较与传统PI矢量控制,跟踪精度高、响应快、抗负载扰动强,对实现PMSM的无速度传感器高精度转速跟踪控制具有重要意义。