变频恒压供水系统的Smith预估复合控制

摘要

针对恒压供水系统的非线性、随机性、大惯性和纯滞后特性,提出了一种带Smith预估的PID-模糊复合控制策略.该控制策略融合了模糊控制动态响应性能好、PID控制调节精度高以及Smith预估纯滞后补偿的优点.在保留了系统很好的动态过程平稳性和稳态性能的基础上,明显改善了系统的动态过程快速性,同时对被控对象模型参数变化具有很好的适应性,鲁棒性好.仿真试验结果表明:带Smith预估的PID-模糊复合控制策略可使恒压供水系统的动态稳态性能明显优于常规PID、模糊控制和PID-模糊复合控制.%A PID-fuzzy control strategy with Smith predictor was proposed for the constant pressure water supply system,which had the characters of nonlinearity,randomicity,large inertia and big delay.This control strategy combined the advantages of good dynamic response of fuzzy control,high regulation accuracy of PID control and pure lag compensation of Smith predictor.On the basis of retaining the system' s stationarity,dynamic process and steady state performance,this control strategy could evidently improve the speedability of dynamic process,had good robustness and well adaptability to variational model parameters.The simulation results showed that PID-fuzzy control strategy with Smith predictor could make the dynamic and steady performance of constant pressure water supply system better than conventional PID control,fuzzy control and PID-fuzzy integrated control.