基于PLC的水力发电机组模糊控制器

Design of fuzzy controller based on PLC for hydroelectric unit

针对水力发电机组模型参数的不确定性、时变性以及运行工况的复杂性,应用模糊控制理论设计了适用于水力发电机组应用的模糊比例积分微分(PID)控制器。该控制器采用二维控制方式,以e(t)和Δe(t)为输入语言变量,以KP、KI和KD为输出语言变量,分别量化为5个等级,并根据水力发电机组的实际运行经验构造出相应的模糊控制规则。通过模糊运算,得到了水力发电机组不同工况下PID控制器的不同参数,实现了对水力发电机组的模糊控制。在此基础上,设计了基于PLC的模糊控制程序。对水力发电机组采用模糊PID控制器和传统PID控制器的动态行为进行比较后表明,采用模糊PID控制器的水力发电机组具有更好的动态品质。

Because of the uncertainty and the time-changing of hydroelectric unit model as well as the complexity of its operating conditions,the fuzzy PID（Proportional Integral parameters, Derivative） controller is designed for hydroelectric unit. It adopts dual-dimensional control method,taking e（t） and △e（t） as input elements,Kp,K1 and Kd as output elements,divided into five grades respectively. The fuzzy control rule is constructed according to actual operation experiences and different parameters of the PID controller are obtained through fuzzy calculation for different operating conditions. The fuzzy control programs are written for PLC（Programmable Logic Controller）. Compared with conventional PID controllers,the dynamic performance of fuzzy PID controller is better for hydroelectric unit.