基于间隙度量的主汽温多模型Smith预估控制

Multiple Model Smith Predictor Control of Main Steam Temperature based on Gap Metric

针对电站主汽温对象的大滞后和非线性,提出一种多模型Smith预估控制策略。基于系统间隙度量建立对象的多模型集并合理选择工况点设计控制器使得系统全局稳定,依据负荷工况的变化采用递推贝叶斯公式完成多模型的切换,利用一阶惯性加纯滞后模型的经验公式整定PID参数。仿真实验研究表明:基于间隙度量建立对象多模型集并设计控制器可以有效地克服模型失配,同时避免了控制器切换引入的干扰。该方法具有良好的负荷适应能力,进一步提高了锅炉主汽温系统的控制品质。

For the large time-delay and the nonlinear of the main temperature plant,a multiple model Smith predictor control strategy is proposed.Based on the gap metric,a set of multiple models is established.At the same time,the working point is selected carefully and reasonably to design the controller in order to ensure the control system stable at other working points.According to the change of boiler load,the switching between multiple models is designed by the recursive bayes formula.Finally,the empirical formula of first-order-inertia-dead-time process is used to tune PID parameters.It can effectively overcome model mismatch and avoid disturbance caused by controller switching through the multiple model Smith predictor control strategy.The simulation results show that the method presented has good load adaptability,which can further improve the control performance of the main steam temperature system.