Accurate Transient Power Allocation for VSGs Based on Virtual Impedance Matching and Coordinated Parameter Optimization

Transient power allocation imbalance among pa -rallel Virtual Synchronous Generators (VSGs) inverters caused by mismatched line impedances. This paper proposes a communication-free method to improve transient power sharing accuracy among VSGs in renewable-rich microgrids. Addressing line impedance mismatch and circulating currents, the method integrates online impedance estimation with capacity-proportional virtual impedance compensation. A circulating current included small-signal model enables cooptimization of virtual inertia and damping parameters via stability analysis, accelerating transient power convergence. System dynamics are evaluated using center-of-inertia frequency derived from rotor swing equations. Simulations are performed to validate confirm precise proportional power allocation during transients, eliminating overloading in small-capacity VSGs while significantly enhancing frequency nadir and stability.