Decentralized Periodic Event-Triggered Frequency Regulation for Multi-Area Power Systems

In order to improve the control performance of load frequency control for multi-area power systems, this paper proposes a decentralized periodic event-triggered control (DPETC) approach to replace the traditional periodic sampling mechanism in automatic generation control (AGC) for communication scheduling. In each control area, the communication is enforced via two unidirectional communication channels, i.e., one is to transfer the local measurements from the power plants to the control center and the other is to transfer the updated control signals from the control center to the power plants. A decentralized event-triggering condition is designed for each communication channel, which is evaluated periodically and only depends on the local measurements. However, AGC executes the unidirectional communication only when the corresponding event-triggering condition is fulfilled. Small disturbance frequency stability of the system under the proposed DPETC method is investigated, and a sufficient stability criterion is established. Simulation studies on a three-area interconnected system validate the effectiveness of the proposed method.