基于滑模观测器的异步电动机速度传感器故障诊断及容错控制

Fault diagnosis and fault tolerant control based on sliding mode observer for speed sensor in asynchronous motor

针对异步电动机矢量控制系统中速度传感器故障问题,提出基于滑模观测器的故障诊断及容错控制方法。通过坐标变换的方法建立异步电动机的状态空间模型,从而构造滑模观测器,并使用李雅普诺夫稳定性理论求解稳定性条件并给出转速自适应律;设计矢量控制系统的转速切换策略,当残差信号大于给定阈值时使系统切换到无速度传感器矢量控制方式,保持异步电动机稳定运行。仿真结果表明该方法可以在0.2 s内实现故障检测,并使系统稳定运行,体现出该方法的快速性和有效性。

Aiming at the fault appearing in speed sensor of asynchronous motor in vector control system, a sliding-mode observer based fault diagnosis and fault tolerant control method was proposed. The state space model of asynchronous motor was established by coordinate transformation method, the sliding mode observer was then constructed the stability conditions and speed adaptive law were derived by Lyapunov stability theory. The switching control strategy was designed to guarantee the safety of the induction motor, which changed system working mode into speed sensorless vector control when the residuals were larger than the given thresholds. The developed method could detect faults within 0. 2 s and recover the performance of the system, whose rapidity and effectiveness was validated via a simulation experiment.