基于ESN的多指标DHP控制策略在污水处理过程中的应用

Application of ESN-based Multi Indices Dual Heuristic Dynamic Programming on Wastewater Treatment Process

针对污水处理过程(Wastewater treatment process,WWTP)溶解氧(Dissolved oxygen,DO)及硝态氮浓度控制问题,提出了一种多评价指标的DHP(Dual heuristic dynamic programming)控制策略.该策略能够降低评价指标的复杂性,提高评价网络的逼近精度.采用回声状态网络(Echo state networks,ESNs)实现评价函数及控制策略的逼近,研究了控制器的在线学习算法.实验表明,该策略在控制性能上优于单评价指标的DHP策略及常规PID控制策略.

In order to solve the problem of controlling dissolved oxygen（DO） concentration and nitrate concentration of waster-water treatment process（WWTP）,a multi critic indices dual heuristic dynamic programming（MDHP） policy is proposed.The approximating precision can be improved through lowering the complexity between the relationship of the critic network s outputs and inputs in this scheme.Echo state networks（ESNs） are adopted to approximate the critic indices and the optimal control policy.Online learning method of the controller is inves-tigated.Experimental results indicate that the MDHP scheme has some advantages over single critic index DHP（SDHP） and PID in control performance.