火力发电厂SCR烟气脱硝滑模变结构优化控制

Optimized Sliding Mode Control of Power Plant SCR Flue Gas Denitration System

针对火力发电厂氮氧化物排放限制日渐严格的现状,以SCR烟气脱硝系统为研究对象,设计了调节量输出幅值与变化速率受限前馈补偿的控制方案,设计了虚拟滑模面控制策略,并引入串级差分进化算法实现了系统自适应滑模变结构控制;在前述基础上进一步设计了基于串级差分进化算法的无差自适应滑模变结构控制策略。仿真结果表明,所设计的控制方案能够满足SCR烟气脱硝系统控制需求,鲁棒性好,控制品质优于常规方案,对现场实际有一定的指导意义。

Along with the consciousness of environment protection increased, the limitation of allowed emission of nitrogen oxide from power plant becomes more and more rigorous. Study the model of SCR flue gas denitration system as the controlled plant, the design that the limitation of amplitude and changing rate of control variable is used as feed-forward compensation is proposed;using differential evolution algorithm to bring the ability of adaptive to the designed sliding mode control system by the help of the designed auxiliary sliding surface. Based on the proposals mentioned above, the offset free adaptive optimized sliding mode control by using cascaded differential evolution algorithm is presented. The simulation results indicate that the optimized control systems gave above could reach the control requirement of SCR flue gas denitration system,their control quality and robustness are better than traditional way, and the practical significance is proved.