Event-Triggered Coordinated Control of Frequency and Voltage for Multi-Energy Microgrid

With the increasing proportion of power electronic devices in multi-energy microgrid cluster systems, the inertia level of the system continues to decrease, posing severe challenges to the control of system frequency and voltage stability. To improve the frequency and voltage stability of multi-energy microgrid cluster systems, this paper proposes an event-triggered multi-energy microgrid control method to enhance voltage stability. Firstly, this paper analyzes the reactive power and voltage characteristics of multi-energy systems, and constructs stability control models for multi-energy microgrids considering gas network response and thermal network inertia. Aiming at studying the lagging response characteristic of the gas network, a coupling model including the dynamic characteristics of natural gas pressure regulating stations and gas pipelines is established to reveal the transmission mechanism of gas network pressure fluctuations on the output of distributed power sources. Secondly, focusing on the thermal network inertia, the buffering effect of thermal inertia on the power balance of the power grid is clarified by quantifying the heat storage capacity of the thermal pipelines. Then, for voltage control, an event-triggered mechanism based on model prediction is established to adaptively adjust the update timing of control commands, achieving rapid correction of voltage deviations. Finally, for frequency control, a multi-time-scale response framework is constructed, utilizing the millisecond-level response of energy storage systems, the medium-term support of gas turbines, and the long-term buffering of thermal network inertia to form a frequency stability system covering the entire disturbance cycle.