感应电动机拖动装置的滑动模控制

SLIDING MODE CONTROL FOR INDUCTION MOTOR DRIVES

本文针对感应电机运行时参数变化范围大，存在负载扰动的情况。用两种方法进行解耦滑模控制．前半部分将变结构模型参考自适应控制理论应用到系统中，使系统具有较好的动态响应与鲁棒性，并给出了仿真结果．后半部分则运用滑模理论对系统内环直接进行解耦和控制，而外环采用常规控制，实验结果证实了该方法的有效性。比较而言，后者更易于实现，鲁棒性更强。

A novel control approach of Variable Structure Model Reference Adaptive Control (MRAC) for a robust induction motor drive system has been developed in the first part of this paper. Induction motor drive system has a system parameter variation in wide range and loaddisturbance during operation.To solve this problem,in the former part,the motor is decoupled withslip frequency control based on the synchronous two-axis coordinate theory,then rotor flux andtorque can be controlled respectively.In addition,a variable structure adaptive speed regulator employing the MRAC is incorporated into the drive system to compensate for unfavorable errors.The principles and special features of the variable structure control scheme are discussed.Sedation results also showed the robustness and superior dynamic Performance of the proposed controlalgorithm.In the second part of the paper.a new sliding mode control method is presented.Thecontrol algorithm is based on the model of induction motor in the frame rotating sychronously with the stator current vector,the method allows the rotor flux and torque to be controlled by two control variable seperately too.But it is mole insenstive to motor parameter and it has a fastresponse,simplicity of design and implementation.The sliding mode is applied to decouple the motorand control the inner-loop torque variable.A PI regulator is introduced into the outer speed-loopto control the speed system.Test results have verified the advantage of tile proposed method.