预估型氨法脱硫控制系统研究

Research on Predictive Ammonia Desulfurization Control System

燃煤发电系统中氨法脱硫控制系统具有时变、大延时、大惯性的特点。针对典型的大延迟系统,文中提出基于Smith预估器的脱硫控制系统,通过抵消系统被控对象中的纯滞后环节来提高系统的实时性。Smith预估器依赖准确的PID模型,系统中PID参数整定仍存在不确定性。利用SOA算法对PID参数进行整定,将绝对误差积分ITAE作为适应度函数,通过对适应度值的不断寻优,找到最佳的比例积分微分系数组合。仿真结果表明,相较于Smith预估器控制下的脱硫系统,基于SOA的Smith预估PID控制系统跟随性好且反应迅速,调节时间缩小为原来的9%,峰值时间缩小为原来的5%,具有较小的超调量,系统的实时性和稳定性得到保证。上述结果证明该算法对工程控制系统有效,并具有良好的应用前景。

The ammonia desulfurization control system in the coal-fired power generation system has the characteristics of time-varying,large delay and large inertia.Aiming at the typical large delay system,a desulfurization control system based on Smith predictor is proposed to improve the real-time performance of the system by offsetting the pure delay link in the controlled object.The Smith predictor relies on an accurate PID model,and there are still uncertainties in the PID parameter tuning in the system.The SOA algorithm is used to adjust the PID parameters,and the absolute error integral ITAE is used as the fitness function.Through the continuous optimization of the fitness value,the best combination of the proportional integral differential coefficient is found.The simulation results show that compared to the desulfurization system under the control of Smith predictor,the new system has good follow ability and rapid response,the adjustment time is reduced to 9%of the original,and the peak time is reduced to 5%of the original,and has a very small overshoot.The real-time and stability of the system are guaranteed.These results indicate that the algorithm is effective for engineering control systems and has a good prospect of popularization and application.