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1.
    
This paper presents a new adaptive robust control for induction motor drives. The proposed control scheme is based on the so‐called field oriented control theory that allows to control the induction motor like a separately excited direct current motor drive, where the field flux (produced by the field current) and the armature flux (produced by the armature current) are decoupled. The robust control law is based on the sliding mode control theory, but unlike the traditional sliding mode control schemes, the proposed design incorporates an adaptive switching gain that avoids the need of calculating an upper limit of the system uncertainties. Moreover the proposed control law is smoothed out in order to avoid the high control activity inherent to the switching control laws. The resulting closed loop system is proven to be stable using the Lyapunov stability theory. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society  相似文献   

2.
    
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.  相似文献   

3.
提出一种具有自适应能力的非奇异快速终端滑模控制(NFTSMC)方法, 可有效提升在外部扰动和参数变化下的异步电动机速度控制性能. 首先, 提出一种自适应非线性控制方法, 在增强系统抗干扰能力和动态响应性能的同时, 抑制滑模抖振现象; 其次, 提出的滑模负载转矩观测器(SMLTO)能够在负载转矩发生波动时, 迅速准确地跟踪到实际转矩, 从而减少负载转矩突变带来的速度波动, 提升控制精度和鲁棒性. 此外, 采用非奇异终端滑模控制方法, 不仅能加速系统状态的收敛, 还可避免传统滑模控制中的奇异性问题. 实验结果表明, 所提方法可显著提高异步电机速度控制系统的鲁棒性和响应速度, 并展现出优异的负载转矩观测性能.  相似文献   

4.
论述了滑模变结构多电平变换器系统的基本控制原理,深入分析了滑模变结构控制方法的原理和实现方法,设计了滑模多电平变换器驱动异步电动机系统.在MATLAB/simulink平台上对其进行仿真,仿真结果表明滑模变结构多电平变换器有优良的输出特性,这将为多电平变换器在高性能的交流调速闭环控制系统中的具体实用打下基础.  相似文献   

5.
    
The authors propose a robust nonlinear controller based on a block control linearization technique combined with a second order sliding mode super‐twisting algorithm for controlling the rotor speed of single‐phase induction motors. The block control approach is used to design a sliding manifold in terms of the stator current and its desired value. The super‐twisting sliding mode algorithm is applied then to render the designed manifold be attractive. A nonlinear observer is designed to estimate the unmeasured variables (rotor flux linkages and torque load). Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

6.
黄文涛 《工矿自动化》2011,37(12):52-55
感应电动机是一个高阶、非线性、强耦合的多变量系统,在运行的过程中参数易受温度、负载变化的影响,会造成电动机进入不稳定区域运行。为了适应系统的非线性特性,提出了一种基于滑模变结构的控制策略。该策略对电流、转速、磁链误差分别建立滑模面,构造出各环节变结构控制器,并推导出自适应控制律。仿真结果证明了控制策略的有效性和可行性。  相似文献   

7.
This paper proposes a sliding‐mode linearization torque control (SMLTC) for an induction motor (IM). An ideal feedback linearization torque control method is firstly adopted in order to decouple the torque and flux amplitude of the IM. However, the system parameters are uncertainties, which will influence the control performance of the IM in practical applications. Hence, to increase the robustness of the IM drive for high‐ performance applications, this SMLTC aims to improve the immunity of those uncertainties. We modify the flux observer of Benchaib and Edwards [15] by means of the adaptive sliding‐mode method. This not only eliminates the estimation of the uncertainty bounds, but also improves the performance of sliding control. In addition, a practical application of the proposed SMLTC, with a model reference adaptive control (MRAC) scheme incorporated as the inner and outer loop controller used for position control, is also presented. Some experiments are presented to verify the control theory and demonstrate the robustness and effectiveness of the proposed SMLTC.  相似文献   

8.
    
In this paper, a disturbance observer–based adaptive boundary layer sliding mode controller (ABLSMC) is proposed to compensate external disturbance and system uncertainty for a class of output coupled multiple‐input multiple‐output (MIMO) nonlinear systems. To show the effectiveness of the proposed ABLMSC, a traditional adaptive sliding mode controller (ASMC) is also designed. The stability of the closed‐loop system is examined by using the Lyapunov stability approach. The proposed control approach is implemented for a class of nonlinear output coupled MIMO systems. For real‐time validation, a coupled tank system is considered for study. Finally, simulation and real‐time results show that the proposed ABLMSC gives better performance such as reduced chattering and energy efficiency than that of the ASMC and some reported works in the literature.  相似文献   

9.
    
A new high‐order sliding mode controller is proposed. The main features are gain adaptivity and the use of integral sliding mode concept. The gain adaptation allows a reduction of the chattering and gives a solution to control uncertain nonlinear systems whose the uncertainties/perturbations have unknown bounds. The concept of real high‐order sliding mode detector is introduced given that it plays a key role in the adaptation law of the gain. This new control approach is applied by simulation to an academic example to evaluate its efficiency. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

10.
    
This paper presents a passive fault tolerant control approach dedicated to stator inter‐turn short‐circuit fault of an induction machine. This control is based on sliding mode strategy and is implemented for validation on real‐time data acquisition and control platform. The proposed work highlights the integral sliding mode controller benefits during healthy and faulty operations. It can make the induction machine outputs to track their desired reference signals in finite‐time and allows to obtain a better dynamic response performances even in presence of fault. Moreover to avoid the use of a flux sensor, a second order sliding mode observer is used to estimate the rotor flux. Since the used observer converges in finite time, the closed‐loop stability of the proposed system (controller+observer) is proved using the Lyapunov stability theorem. Experimental results are conducted for squirrel cage induction machine to highlight the efficiency and applicability of the proposed fault tolerant control.  相似文献   

11.
针对异步电动机矢量控制系统常规等效滑模控制存在扰动稳态误差大、抖振大、跟踪快速性差的问题,设计了一种改进的等效滑模控制器。该控制器采用改进的切换控制函数,提高了电动机的动态控制性能。仿真试验结果表明,与传统的PI控制器和常规的等效滑模控制器相比,该控制器能有效降低系统抖振,提高了系统的动态响应速度,增强了系统的鲁棒性。  相似文献   

12.
    
In this article, a control design concept using fuzzy sets for an induction motor is presented. The aim of the proposed modelling approach is to provide a fuzzy set-based representation of the cascade sliding mode control of an induction motor fed by PWM voltage source inverter, which operates in a fixed reference frame. For this purpose, a new decoupled and reduced model is first proposed. Then, a set of simple surfaces and associated control laws are synthesised. A piecewise smooth control function with a threshold is adopted. However, the magnitude of this function depends closely on the upper bound of uncertainties, which include parameter variations and external disturbances. This bound is difficult to obtain prior to motor operation. To solve this problem, a fuzzy modelling approach is presented to improve the design and tuning of a fuzzy logic controller using variable structure control theory. The robust fuzzy control design is made feasible without resorting to model simplification or imposing restrictive conditions on the system uncertainty. The fuzzy controller is designed in order to improve the control performances and to reduce the control energy and the chattering phenomenon. Simulation results reveal some very interesting features and show that the proposed fuzzy sliding mode controller could be considered as an alternative to the conventional sliding mode control of induction motors.  相似文献   

13.
永磁同步电动机新型自适应滑模控制   总被引:1,自引:0,他引:1       下载免费PDF全文
永磁同步电动机(PMSM)是多变量、强耦合、非线性时变系统, 对外界干扰及内部参数摄动较为敏感, 为提高系统的鲁棒性, 本文提出一种基于非线性滑模面的自适应滑模变结构控制方法. 根据复合非线性反馈控制理论, 为PMSM滑模控制系统设计非线性滑模面, 通过实时改变控制系统的阻尼系数来提高PMSM伺服系统的瞬态响应性能. 在PMSM伺服系统外界扰动及内部参数摄动的上下界未知的情况下, 采用自适应参数校正律来调节控制增益的大小, 改善了系统的抖振现象. 此外, 对电机的电流及转速进行了饱和限制, 使得所设计的伺服控制系统可用于大范围的位移跟踪. 仿真结果表明, 与基于线性滑模面的控制器相比较, 本文所设计的基于非线性滑模面的自适应滑模控制器使得电机转子位移能够更快且无超调的到达给定值, 且系统的抖振现象明显减弱.  相似文献   

14.
A robust sliding mode approach combined with a field oriented control (FOC) for induction motor (IM) speed control is presented. The proposed sliding mode control (SMC) design uses an adaptive switching gain and an integrator. This approach guarantees the same robustness and dynamic performance of traditional SMC algorithms. And at the same time, it attenuates the chattering phenomenon, which is the main drawback in actual implementation of this technique. This approach is insensitive to uncertainties and permits to decrease the requirement for the bound of these uncertainties. The stability and robustness of the closed- loop system are proven analytically using the Lyapunov synthesis approach. The proposed method attenuates the effect of both uncertainties and external disturbances. Experimental results are presented to validate the effectiveness and the good performance of the developed method.  相似文献   

15.
针对感应电动机常规直接转矩控制中存在磁链、转矩脉动大,低速控制不精确等问题,在建立α-β坐标系感应电动机数学模型的基础上,提出了一种基于滑模变结构的新型直接转矩控制方法。该方法利用转速滑模变结构控制器代替常规直接转矩控制中的PI控制器,可有效减小常规直接转矩控制中的磁链和转矩脉动,增强了系统的稳定性。仿真结果证明了该方法的正确性。  相似文献   

16.
    
This paper presents a robust fault tolerant control for an induction motor in presence of inter‐turn short‐circuit fault. The control strategy is based on Backstepping approach and high order sliding mode observer. That ensures a high‐performance control and a good dynamic in presence of inter‐turn short‐circuit fault. The stability of the Backstepping control is proved by Lyapunov theory. A high order sliding mode observer is used for rotor flux estimation. The performances of the fault tolerant control scheme will be examined via numerical simulation and validated through hardware implementation using MATLAB/Simulink with dSpace signal card. The analysis' results show the robustness of the proposed method for the tolerance of the inter‐turn short‐circuit fault.  相似文献   

17.
感应电机高阶终端滑模磁链观测器的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
史宏宇  冯勇 《自动化学报》2012,38(2):288-294
提出了基于高阶非奇异终端滑模的感应电机转子磁链观测方法,用于实现感应电机的按转子磁链定向控制. 设计了非奇异终端滑模面及观测器的控制策略,利用所设计的控制策略推导出电机转子磁链信息. 为了抑制常规滑模存在的抖振现象,设计了定子电流观测器的高阶滑模控制律,可将控制信号直接用于电机转子磁链的估计. 较常规滑模观测器,所提方法具有较高的观测精度,并对电机参数变化具有良好的鲁棒性.仿真结果验证了方法的有效性.  相似文献   

18.
    
A sensorless speed/position tracking control scheme for induction motors is proposed subject to unknown load torque via adaptive strictly positive real (SPR) approach design. A special nonlinear coordinate transform is first provided to reform the dynamical model of the induction motor. The information on rotor fluxes can thus be derived from the dynamical model to decide on the proportion of input voltage in the d-q frame under the constraint of the maximum power transfer property of induction motors. Based on the SPR approach, the speed and position control objectives can be achieved. The proposed control scheme is to provide the speed/position control of induction motors while lacking the knowledge of some mechanical system parameters, such as the motor inertia, motor damping coefficient, and the unknown payload. The adaptive control technique is thus involved in the field oriented control scheme to deal with the unknown parameters. The thorough proof is derived to guarantee the stability of the speed and position of control systems of induction motors. Besides, numerical simulation and experimental results are also provided to validate the effectiveness of the proposed control scheme.  相似文献   

19.
异步电动机的非线性自适应控制   总被引:3,自引:0,他引:3       下载免费PDF全文
本文针对对磁场定向的d-q坐标系下的4阶包含机、电动力学的异步电动机的模型,运用非线性自适应的反馈线性化的控制方法,设计一个新近跟踪负载和转子电阻实际值的非线性辩识算法,一旦这两个未知常数被辩识,则可实现速度和磁链调节的解耦控制,仿真结果证明系统具有良好的稳、动态性能。  相似文献   

20.
    
The introduction of electric braking via brake‐by‐wire systems in electric vehicles) has reduced the high transportation delays usually involved in conventional friction braking systems. This has facilitated the design of more efficient and advanced control schemes for antilock braking systems (ABSs). However, accurate estimation of the tire‐road friction coefficient, which cannot be measured directly, is required. This paper presents a review of existing estimation methods, focusing on sliding‐mode techniques, followed by the development of a novel friction estimation technique, which is used to design an efficient ABS control system. This is a novel slip‐based estimation method, which accommodates the coupling between the vehicle dynamics, wheel dynamics, and suspension dynamics in a cascaded structure. A higher‐order sliding‐mode observer–based scheme is designed, considering the nonlinear relationship between friction and slip. A first‐order sliding‐mode observer is also designed based on a purely linear relationship. A key feature of the proposed estimation schemes is the inclusion of road slope and the effective radius of the tire as an estimated state. These parameters impact significantly on the accuracy of slip and friction estimation. The performance of the proposed estimation schemes are validated and benchmarked against a Kalman filter (KF) by a series of simulation tests. It is demonstrated that the sliding‐mode observer paradigm is an important tool in developing the next generation ABS systems for electric vehicles.  相似文献   

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