Fault ride-through capability enhancement by adapative voltage support control for inverter interfaced distributed generation

In order to meet the grid code of distributed generation and avoid intolerable over-voltage of dc-side on the occurrence of grid faults at the same time, an adaptive voltage support control strategy for low voltage ride-through (LVRT) of inverter interfaced distribution generation (IIDG) is proposed. Firstly, according to the request of German grid code, the basic control strategy and the fault current characteristic of IIDG are studied. Then, based on analyzing the effect of reactive power supplied by IIDG to the point of common coupling (PCC) voltage, this paper proposed an adaptive voltage support control strategy to enhance the fault ride-through capability of IIDG. Finally, simulation results demonstrate the proposed control strategy has advantage of improving to PCC voltage support capability and helping to ensure the safety of the IIDG equipment.