Knowledge Compensation-Based Active Fault-Tolerant Control for Wastewater Treatment Process
针对污水处理过程中不确定性和外部干扰导致的未知故障，提出一种基于知识补偿的主动容错控制方法，通过知识预设性能函数和知识补偿机制重构控制律，确保系统在故障下仍能安全稳定运行，仿真和实际案例验证了其有效性。
fault-tolerant control (FTC), due to its characteristic of fault prevention and mitigation, is an increasingly popular topic in wastewater treatment process (WWTP) for safety purpose. However, the presence of uncertainties and external disturbances inevitably leads to unknown faults in WWTP, making it challenging for FTC strategies using existing fault data to ensure continuous safe and stable operation. To address this issue, a knowledge compensation-based active fault-tolerant control (KC-AFTC) is designed in this article. First, a knowledge-based prescribed performance function (KPPF) is introduced to constrain the transient and steady-state performance of WWTP. Then, the proposed KPPF can assist in KC-AFTC to ensure the operation of WWTP with the desirable performance in the event of faults. Second, a knowledge compensation mechanism (KCM), which is extracted from KPPF and the fault data, is employed to reconstruct the control law for different fault conditions in active FTC (AFTC). Then, KC-AFTC can maintain the continuously safe and stable operation of WWTP. Third, the stability of knowledge compensation-based AFTC (KC-AFTC) is demonstrated through Lyapunov theory. Then, the stability analysis can provide theoretical basis for further application of KC-AFTC in practical experiments. Finally, the proposed control method is validated through both a simulation case and a real WWTP. The results demonstrate that KC-AFTC can achieve outstanding performance in terms of stability and fault tolerance.