With the increasing penetration of low-inertia and weakly damped renewable sources, AC-bus frequency can exhibit pronounced excursions under disturbances. This paper aims to develop an improved adaptive parameter tuning strategy for virtual synchronous generators (VSGs) to enhance frequency stability and dynamic performance.
First, a disturbance feedforward control scheme is incorporated to effectively increase equivalent damping and improve system stability. Second, an improved particle swarm optimization (IPSO) algorithm is used to determine suitable initial values of the proposed controller, and practical selection guidelines and admissible ranges for key parameters are provided. Third, Referencing the power Angle characteristic curve, an adaptive control law based on a power-buffer function is designed to realize fast power build-up, buffered regulation and stable control in the early stage of disturbances. Finally, the proposed strategy is evaluated via simulations and validated on an RT-LAB hardware-in-the-loop (HIL) platform.
Simulation and RT-LAB HIL results demonstrate that the proposed strategy significantly improves the VSG’s frequency response and active-power dynamic characteristics under disturbances, effectively suppressing frequency fluctuations and enhancing overall system stability.
Unlike existing approaches that tune VSG parameters independently, this work presents a coherent adaptation framework that couples damping enhancement, intelligent initialization and stage-aware power buffering, offering improved transient performance and implementation practicality for renewable-dominated grids.
