Abstract: With the large-scale integration of distributed new energy into distribution networks, the main grid power flow weakens, causing excessively high and hard-to-regulate static voltage. However, the reactive power compensation capacity of static var generator (SVG) in existing centralized photovoltaic (PV) power plants remains underutilized. To solve these issues, a reactive power compensation strategy with active adjustment for PV-integrated power plants based on an improved holomorphic embedding method (HEM) is proposed. The traditional holomorphic embedding power flow (HEPF) method is modified to build an improved HEPF model, which fully utilizes the reactive power compensation capacity of centralized PV power plants and optimizes the siting and sizing of additional reactive power compensation devices. This strategy enhances power system voltage stability and reduces the investment cost of such devices. Simulations on a modified IEEE 39-bus system show that the power system voltage stability is effectively improved, and the total installed capacity of reactive power compensation devices is reduced by approximately 20%.

Key words: steady-state overvoltage, holomorphic embedding, reactive power compensation, centralized photovoltaic power plants