Quantitative Evaluation Method for Regulation Capability of Grid-Forming Controlled Photovoltaic-Energy Storage Substation

With the extensive integration of distributed generation, there have been significant changes in the form and power composition of the distribution network. Among them, the integrated connection of photovoltaics and energy storage to distribution network substations is a typical application scenario for the high proportion integration of distributed generation. The stochastics and fluctuation of the distributed generation take significant challenges to the operation and control of distribution networks. However, with the gradual maturity of grid-forming control technology, the power control of photovoltaic and energy storage substations has become a feasible possibility. Accordingly, an equivalent power response model for photovoltaic and energy storage substations is constructed in this paper first. The active regulation characteristics of photovoltaics and energy storage were analyzed separately. Considering different operating states of photovoltaic and energy storage substations and different power commands, a quantitative calculation method for the regulation range and regulation speed of photovoltaic and energy storage substations is provided. At last, the proposed calculation method is validated through simulations on the PSCAD/EMTDC experimental platform.