基于Smith预估的模糊PID串级中央空调水系统控制

摘要

为了避免部分负荷下空调运行所造成的能量损失,需对空调水系统进行变流量控制.针对一次泵水系统,采用一种带Smith预估的模糊PID复合串级控制系统,对最不利支路上压差和冷水机组回水温度进行串级优化控制.主控制器采用模糊PID参数自调整控制器.为消除纯延迟,副回路中加入Smith预估控制器.Matlab仿真结果表明,新的串级控制系统相比常规PID控制,响应速度快,具有良好的静态性能.%The control of variable water flow can avoid power losses caused by air condition under partial load. For the characteristics of the primary flow, the fuzzy PID composite serial control system with Smith predictive, estimate is adopted. The main controlled variable is the temperature of chilled return water, and fuzzy PID controller of automatic regulation is used. Smith predictive estimator is adopted in the minor loop to eliminate delay, and the variable is the pressure on worst side. The Matlab simulation shows that the new serial control system, compared with general cascade control, has excellent static performance and fast response speed.