Research on Fractional-Order Virtual Synchronous Generator Control with Fuzzy Adaptive Inertia and Damping Regulation

Abstract

Conventional virtual synchronous generators (VSGs) employ fixed inertia and damping parameters, resulting in insufficient adaptability to varying operating conditions. Moreover, virtual inertia may cause active-power overshoot and dynamic oscillations and slow down the transient response. To address these issues, a fractional-order VSG control strategy with fuzzy adaptive inertia and damping regulation is proposed. A small-signal model of the active-power loop is established to analyse the oscillation mechanism and the effects of key parameters on system dynamics. A fractional-order inertia element is introduced to improve the power-frequency dynamic response, while a fuzzy controller adjusts the virtual inertia and damping coefficients online according to the system dynamic state. The proposed strategy is validated under multiple operating conditions, together with sensitivity and robustness analyses. Simulation results show that, compared with the conventional VSG, the proposed strategy reduces the active-power overshoot ratio from 38.84% to 0.95% under an active-power reference variation. Under a grid-frequency disturbance, the maximum power deviation and maximum frequency deviation are reduced by 1.710 kW and 0.0374 Hz, respectively. Further simulations under varying operating conditions demonstrate that the proposed strategy maintains good dynamic performance and robustness. The proposed method achieves a favorable balance among power-oscillation suppression, frequency support, and robustness, providing an effective control solution for grid-connected PV-storage systems with high renewable-energy penetration.