Research on Unified Model for Active Powerfrequency Response in Grid-Forming Control

With the increasing penetration level of renewable energy in power systems, grid-forming renewable energy sources which are capable of autonomously establishing voltage amplitude and phase angle have attracted significant attention. Grid-forming control strategies have evolved through successive developments including P-f droop control, Virtual Synchronous Generator (VSG) control, and DC voltage matching control. Despite the rapid advancement in grid-forming technologies, the field currently lacks a unified modeling framework and analytical methodology capable of accommodating diverse control strategies for investigating frequency response characteristics and active power support mechanisms in gridforming renewable energy systems. grounded in their operational principles, this paper establishes control-specific mathematical models characterizing active power-frequency transfer dynamics for each strategy. Through comparative analysis, a generalized active power-frequency transfer function is derived, with particular emphasis on its advantages in parameter tuning optimization. The proposed methodology is validated via detailed case studies implemented in DIgSILENT PowerFactory.