GWO‐PSO‐RBF Based Sub‐Synchronous Oscillation Suppression Strategy for Virtual Synchronous Generator Grid‐Connected Systems

ABSTRACT The virtual synchronous generator (VSG), characterized by its voltage source behavior, is capable of providing damping and frequency support to the grid, thereby enhancing the stability of sub‐synchronous and super‐synchronous oscillations when integrating renewable energy units into weak grids. However, under strong grid conditions, oscillation risks arise in the sub‐synchronous negative damping region due to frequency coupling. This paper combines optimization algorithms with neural networks to propose a sub‐synchronous oscillation suppression method based on grey wolf optimization‐particle swarm optimization‐radial basis functions (GWO‐PSO‐RBF), thereby enhancing the stability of VSG integration into strong grids. First, the sequence impedance model of the VSG is established, and system stability is analyzed using the generalized Nyquist criterion, which identifies the potential sub‐synchronous oscillation frequency bands. Subsequently, the influence of various parameters on the grid‐connected system's impedance characteristics is examined, enabling the targeted reshaping of impedance characteristics in the sub‐synchronous frequency range to effectively suppress oscillations in the desired frequency band, thereby enhancing the stability of the VSG grid‐connected system in a strong grid environment. Finally, the effectiveness of the impedance reshaping control strategy was verified through simulation and a hardware‐in‐the‐loop platform.