Reactive power decoupling control strategy for the grid-forming photovoltaic DC/AC converter

• The active power and reactive power coupling principle of the conventional grid-forming photovoltaic DC/AC converter is analyzed. • A reactive power decoupling control strategy is proposed. • The impact of key parameters on the grid-forming photovoltaic stability is analyzed. • The controller hardware-in-the-loop experiment is designed for verification. The grid-forming photovoltaic system (GFM-PV) can actively build up voltage without relying on the grid and exhibit voltage source characteristics. This paper proposes a reactive power decoupling control strategy for the problem of active and reactive power coupling in GFM-PV. Firstly, this paper analyzes the coupling principle of the active power and the reactive power of the GFM-PV DC/AC converter and proposes the reactive power decoupling control strategy. Then, this paper studies the influence of the DC/AC converter key parameters on the power stability of GFM-PV based on impedance analysis. Finally, the controller hardware-in-the-loop (C-HIL) experiments verify the effectiveness of the control strategy proposed in this paper and the correctness of the theoretical analysis.