The application of resonant controller to fulfill LVRT requirements in grid connected VSI

LVRT requirements (Low Voltage Ride Through) demand Renewable Energy Conversion Systems (RECS) to remain connected to the grid in the presence of grid voltages dips. This paper considers an active front-end converter of a grid connected DCCS working under grid fault conditions. A novel control strategy is proposed, based in to maintain active power constant through grid-voltage dips using Resonant Controllers instead the traditional d-q axis strategies. The performance of this strategy is studied on LVRT requirements fulfillment. Experimental results obtained with a small 3kVA prototype are presented and fully analysed in this paper. The experimental results show that proposed strategy is able to achieve the LVRT requirements.