模糊自整定PID控制在主汽温控制中的应用

Application of Fuzzy Self-Tuning PID Controller in Main Steam Temperature Control

火电厂主汽温控制系统中的被控对象具有大滞后、大惯性等特点,并且影响主汽温变化的因素有很多,主蒸汽流量、减温水流量、烟气温度都会使其发生变化,因此很难用传统的PID控制将被调量控制在规程中允许的偏差范围内。而主汽温作为锅炉的主要参数之一,其稳定性对电厂的安全经济运行有至关重要的作用,因此将模糊控制和PID控制相结合,设计了模糊自整定PID控制器,实现了PID控制器参数的在线自整定。仿真结果表明,模糊自整定PID控制比常规的PID控制超调小且调节时间短,具有比较好的应用前景。

The control object in main steam temperature control system is of long time delay, large inertia, and so on. There are many factors that impact the main steam temperature, such as main steam flow, desuperheating water flow and flue gas temperature. So it is difficult to be controlled within the allowed deviation by using traditional PID control method. As one of the main parameters of a boiler, the stability of the main steam temperature is very impor- tant for the safety and economical operation of the plant. In this paper, we designed a fuzzy self - tuning PID control- ler by combining fuzzy control with PID control. Online self - tuning of the parameters of PID controller was realized. Simulation results show that smaller overshoot and shorter regulation time can be obtained by using the fuzzy self- tuning PID control.