污水处理过程多变量自适应变论域模糊控制

Multivariable Adaptive Variable Universe Fuzzy Control for Wastewater Treatment Process

由于污水处理过程具有非线性、时变性和滞后性的特点,传统控制方法难以取得满意的控制效果。为了实现精确跟踪控制,提出了一种基于自适应变论域模糊控制(adaptive variable universe fuzzy control,AVUFC)的污水处理过程多变量控制方法,实现了溶解氧和硝态氮的底层回路控制。在AVUFC中,根据性能指标设计了基于自适应差分进化算法的伸缩因子调整策略,在线自适应调节模糊控制论域,降低工况变化对控制器性能的影响,提高控制器的动态性能和稳态精度。利用国际基准仿真平台BSM1进行实验验证。仿真结果表明,当入水流量和组分浓度发生剧烈变化时,所提出的自适应变论域模糊控制策略能够通过在线优化模糊规则以快速适应复杂工况;与PID控制、模糊逻辑控制、定式变论域模糊控制等方法相比,自适应变论域模糊控制在平稳性、抗干扰性和瞬态响应能力方面更具优势。

Since the wastewater treatment processes(WWTPs)have the characteristics of nonlinearity,time variability,and large time delay,it is difficult to achieve satisfactory control effect for the traditional control methods.To realize accurate tracking control,a multivariable control method of WWTPs based on adaptive variable universe fuzzy control(AVUFC)was proposed to realize the bottom loop control of dissolved oxygen and nitrate nitrogen.In AVUFC,a scaling factor adjustment strategy was designed based on adaptive differential evolution algorithm(ADE),which can adaptively adjust the fuzzy control domain on line,reduce the impact of working conditions on the performance of the controller,and improve the dynamic performance and steady-state accuracy of the controller.The international benchmark simulation platform(BSM1)was used for experimental verification.The simulation results show that the proposed AVUFC strategy can quickly adapt to complex working conditions through on-line optimization of fuzzy rules when the inlet water flow and component concentration change sharply.Compared with PID control,fuzzy logic control and fixed variable universe fuzzy control,the proposed AVUFC strategy has more advantages in stability,anti-interference,and transient response.