基于自适应观测器与变结构技术的感应电机控制新方法

New Controlling Methods for Induction Motor Drives Based on Adaptive Observer and Sliding-mode Control

基于感应电机在二相坐标下的数学模型,使用变结构技术与非线性分析方法,设计出由1个基于滑模的转矩与磁链控制器和1个速度自适应磁链观测器非线性控制系统.首先以定子电流与定子磁链为状态变量,采用非线性系统分析方法建立误差状态方程,然后在使误差渐近收敛为零的原则下设计滑模流形面,根据Layapunov稳定性条件,推导出电阻估计表达式及用于逆变器输入的定子电压控制律.利用基于模型参考与状态反馈的速度自适应磁链观测器来完成转速辨识与磁链的准确观测,分析得到观测器的收敛条件及自适应率,证明了其稳定性,将其估计值作为变结构控制器的输入完成系统的闭环控制.并进行了基于M atlab的仿真与分析,结果证明了控制策略的正确性与有效性.

This paper proposes a new nonlinear controller, which is composed of a sliding-mode controller and a speed adaptive observer, for induction motor （IM） drives on the basis of space vector modulation （SVM） scheme. Firstly, By using the IM model in the stationary reference frame with stator currents and fluxes as state variables, a sliding mode （SM） torque and flux controller is designed in order to track a linear reference model, which has the desired dynamic behaviors of the IM drive system. The SM controller generates the reference voltages for the SVM-PWM inverter to feed the IM. Then, a speed adaptive observer is designed to estimate the flux and the rotor speed. The convergence condition and control law for the estimation algorithm is also obtained by utilizing Lyapunov theory. Finally, computer simulations based on Matlab are done and the results demonstrate the effectiveness and correction of the proposed scheme.