Transient reactive power support strategy of grid-forming type renewable energy based on power-impedance dual-loop control

Grid-forming type renewable energy/energy storage has become an important enabling technology for constructing renewable energy power system, because it could provide inertia and damping for the power grid after disturbances. However, it is prone to overcurrent during fault, which directly limit the reactive power and voltage support ability for power grid. To this end, this paper carried out the targeted research. Firstly, it analyses the current output characteristics of grid-forming type renewable energy under transient conditions. Secondly, it reconstructs the architecture of grid-forming type renewable energy/energy storage control. It proposes a novel transient current limiting strategy based on "power-impedance" dualloop control, and innovatively gives the setting principle of virtual impedance. Finally, the effectiveness is verified through simulation experiments.