An Evaluation Method of the Equivalent Inertia of High-Penetration-Rate Distributed Photovoltaic Power Generation Connected to the Grid

The large-scale integration of distributed photovoltaic power generation leads to increasingly scarce inertia carriers in new power systems. To prevent the frequency of the low-inertia system from dropping too quickly during faults, more extensive inertia response resources need to be urgently explored. Considering that photovoltaic arrays do not have mechanical rotors, it is necessary to configure energy storage with VSM control for photovoltaic power generation units to give them the ability to actively support frequency. Thus, from the perspective of inertia carriers, the contribution of each power generation unit to the stability of the system frequency is quantified, and an equivalent inertia assessment method is proposed for high-penetration distributed photovoltaic power generation connected to the grid considering virtual inertia transformation. Finally, simulation verification is carried out based on the DIgSILENT/Power Factory platform. This research shows that the equivalent inertia assessment method proposed in this paper can effectively reflect the overall inertia level and inertia distribution trend of the system.