AC Series Arc Fault Detection for Wind Power Systems Based on Phase Lock Loop With Time and Frequency Domain Analyses

A wind power system comprises a wind turbine, power converters, connectors, and power lines, making it a highly complex system with an increased possibility of series arc faults at the power components, loose connectors, and damaged power lines. External arc fault detection devices (AFDDs) are utilized to protect the power systems. However, installing AFDDs results in low cost-effectiveness. This article proposes an ac series arc fault detection method based on the rectifier and inverter of wind power systems. This method analyzes the voltage operation considering the arc resistance. The phase lock loop (PLL) structures at the rectifier and inverter are designed to extract the arc fault characteristics and compare them with those obtained under normal operating conditions. The statistical time-domain analysis and fast Fourier transform using the PLL information are coordinated to detect the series arc fault condition. The proposed method can successfully detect the arc fault condition between the wind turbine and rectifier, and between the inverter and grid with only the control algorithm. The experimental results using the 3-kW small-scale wind power systems verified the arc fault detection capability of the proposed method.