Power Decoupling Strategy for Grid-Forming Converter Based on Dynamic Relative Gain Array Calculated Virtual Power

The increasing number of new energy generation makes inertia insufficient becoming an inevitable problem in power grid. Grid-Forming converter (GFM) works as synchronous generator, is one of the answers to new energy generation-based power system. However, power coupling of GFM is a challenge in scenarios such as high impedance and large power angle. In this paper, coupling relationship between power and power angle and impedance ratio is established by Dynamic Relative Gain Array (DRGA) for GFM, while a virtual power control technique based on DRGA and virtual impedance calculation is proposed. Virtual impedance is used to calculate virtual voltage, then the virtual voltage value is fed back to power calculation part to form a virtual power to realize power decoupling. The specific solution methods of virtual resistance and inductance are given based on DRGA constraints. Finally, a simulation model is developed based on Matlab/Simulink platform to verify the proposed decoupling strategy. Simulation results proves that the proposed method has an obvious effect on decoupling active power control and reactive power control loops compare to traditional virtual impedance technique.