Research on Asymmetric Fault Ride Through Control Strategy for Wind Power Based on Three Sequence Current

Asymmetric faults in wind farms may cause fluctuations in active and reactive power, leading to a sharp drop in voltage. In order to reduce the impact of negative sequence current components, balance power fluctuations, and assist in wind turbine low-voltage fault crossing, the power model of grid connected converters during asymmetric faults in wind farms is analyzed, and traditional asymmetric fault control strategies are improved. A wind power asymmetric fault crossing control strategy based on zero sequence current is proposed, zero sequence currents are introduced to construct a zero sequence current control loop, which reduces the negative sequence current component generated by asymmetric faults in the wind farm and the fluctuation of active power in the wind farm, stabilizes the bus voltage. Finally, simulation confirms that the zero sequences current component improves the distribution of positive and negative sequence power, and reduces the fluctuation of grid connected current.