Nonlinear Real-Time Distributed Optimal Control for Frequency Regulation of Cyber–Physical Power Systems

With the increasing penetration of renewable energy sources in power systems, the distributed optimal control (DOC) method has been regarded as an effective way to integrally solve the load frequency control and economic dispatch problem in real time. This article proposes a novel DOC method to deal with the nonlinear characteristics of cyber–physical power systems including physical constraints and time delay. First, based on the integration of the partial primal–dual gradient algorithm and active disturbance rejection control method, this article develops an active disturbance rejection control (ADRC) based DOC method to improve frequency control performance. Then, the positive projection operators are introduced into the ADRC-based DOC method to realize the generation saturation constraints and thermal limits of tie-lines. The stability is theoretically proved by the Lyapunov function. Furthermore, a delay-compensated extended state observer is designed and used to rederive the DOC method to deal with both physical constraints and time delay. Finally, numeral results are obtained with a real-time hardware-in-loop experiment platform and analyzed to verify the effectiveness of the proposed method.