Coordinated Active–Reactive Power Optimization Operation of Distribution Networks with PV–Hydrogen Integration

The integration of distributed photovoltaic (PV) generation enhances the sustainability of distribution networks but brings challenges such as voltage fluctuations, reverse power flow, and increased losses. To address these issues, this paper proposes a coordinated active–reactive power optimization strategy for PV–hydrogen integrated distribution networks. Power models for PV inverters and hydrogen systems are developed, and a hybrid control strategy is designed: PV inverters handle voltage and overload issues, while electrolyzers absorb excess active power to reduce reverse flow. To improve computational efficiency and adaptability, a graph convolutional network (GCN)-based approach is introduced for data-driven coordination. Case studies on the PG&E 69-bus system verify that the proposed strategy maintains voltage stability, reduces losses, and improves economic performance. The hydrogen system achieves profitability under time-of-use pricing and hydrogen sales, demonstrating the strategy’s practical feasibility.