Event-Triggered Sliding-Mode Control for Multi-Area Power Systems

This paper solves the load frequency control problem and proposes a new event-triggered sliding-mode control (SMC) algorithm in multi-area interconnected power systems. First, we consider a three-area interconnected power system, and construct its corresponding mathematical model. The prescribed H∞, or energy-to-energy, performance is utilized to test the effectiveness of the corresponding disturbance attenuation. Then, an appropriate discrete-time integral switching surface is designed for each subsystem, and the discontinuous controller is designed to guarantee the resulting subsystem asymptotically stable and robust. Using time-delay system analysis technique, the event-triggered scheme, sliding mode dynamics, and the network-induced delays are converted into a network dynamic system with time-varying delays. Thus, corresponding sufficient conditions are derived and an event-triggered SMC law for reaching motion is designed to ensure the reachability of the sliding mode surface in a finite time. Finally, examples and simulations are provided to illustrate the feasibility and the effectiveness of the developed event-triggered SMC scheme.