基于增益调整型模糊PID控制的变频恒压供水系统

Variable Frequency Constant Pressure Water Supply System Based on Gain-Schedule Fuzzy-PID Control

针对变频恒压供水系统切泵时由于被控对象参数变化而导致的常规PID控制器控制性能变差,甚至系统运行不稳定的问题,提出了基于系统误差及其变化率实时调整PID参数的方法;设计了增益调整型模糊PID控制器。该控制器可以实现常规PID控制器难以实现的变对象参数控制功能,降低对多台水泵参数一致性的要求,增加多泵组合系统的灵活性。仿真和实际运行表明,系统切换变频泵时该控制器对水压的超调量和系统振荡均能起到很好的抑制作用。

In order to solve the problem that control performance of conventional PID controller becomes worse and even the operation system is unstable caused by controlled object parameter changing as frequency-conversion pump is switched in the variable frequency constant pressure water supply system,an approach to adjust PID parameters real time according to system error and error change rate is proposed,and the gain-scheduling fuzzy PID controller is designed.The controller can achieve variable objective parameters control that conventional PID controller cannot perform,reduce the consistency demand of multi-pump parameters,and increase the flexibility of multiple pumps combined system.The simulation and operation results show that the controller can effectively restrain water pressure overshoot and system oscillating when the frequency-conversion pump is switched.