Smith预估滑模控制在时滞系统中的应用

The Application of Smith Predictive Sliding Mode Control in Time-delay Systems

时滞现象普遍存在于实际控制系统中,给系统控制增加了难度。本文针对含有纯滞后的被控对象,提出一种基于低通滤波的Smith预估滑模控制方法,采用Smith预估器补偿纯滞后环节,引入滑模控制方法提高控制的鲁棒性。同时,针对滑模控制固有的抖振特性,采用低通滤波器对控制信号进行滤波,得到平滑的控制信号。仿真结果表明,基于低通滤波的Smith预估滑模控制方法在时滞系统的控制效果较常规PID控制方法响应速度更快,超调更小。

Delay is common in actual control system, making the system control more difficult. For the controlled object which contains a time delay, a control method based on the low-pass filter and Smith predictor sliding mode control was proposed, the Smith predictor was used to compensate the system delay, sliding mode control was Introduced to improve the robustness of the control, while for chattering characteristic of the sliding mode control, low-pass filter was applied to filtering the control signal and obtain a smooth control signal. The simulation results show that the control method based on the low-pass filter and Smith predictor sliding mode control method response speed is faster, smaller overshoot than the conventional PID control method in time-delay system.