基于IMC-PID的超临界火电机组AGC性能优化

Performance Optimization of AGC for Supercritical Thermal Power Unit Based on IMC-PID

自动发电控制(AGC)功能要求火电机组的负荷响应具有较快的速度和较高的控制精度。常规的AGC采用基于PID的前馈-反馈控制策略,当电网AGC模式改变时,常规AGC策略的性能可能发生恶化乃至引起考核。为了全面优化火电机组的AGC性能,设计了一种基于内模控制PID(IMC-PID)的前馈-反馈功率控制回路,通过构建调节级压力-负荷的传递函数引入内模,在考虑分散控制系统离散控制特性和发电机响应特性的基础上实现控制回路参数整定。最后,将该策略应用在某660 MW超临界机组,结果表明机组AGC性能得到显著提升。

Fast regulation rate and high control accuracy for load response of thermal power unit are necessary for automatic generation control(AGC).Typically,AGC is realized by feedforward-feedback control strategy based on PID regulator,its performance might degrade and even cause undesired punishment when the operating mode of AGC changes.In order to comprehensively optimize AGC performance of thermal power unit,a feedforward-feedback power control loop based on internal model control-PID(IMC-PID) is developed in this paper.In the loop,the internal model is introduced by constructing the transfer function between impulse pressure and load.Then,parameters of the loop are tuned considering the characteristics of distributed control system and generator response.Finally,the control strategy is implemented on a 660 MW supercritical unit.The results indicate that AGC performance of the unit is improved obviously.