The Detection of Parallel Arc Fault in Photovoltaic Systems Based on a Mixed Criterion

This paper presents the problem of parallel arc fault in the DC side of a photovoltaic (PV) system. First, an experimental platform for arc fault of a PV system was built to simulate the DC side parallel arc fault in the PV system. By extracting the current waveform at the exit of PV panels, a study was conducted on the characteristics of the current during parallel arc fault. The result of Fourier transform on the current suggests that the high-frequency component of the current mainly concentrates in the frequency range of 126-250 kHz. According to the analysis of arc fault characteristic in time domain and frequency domain, reversal current maximum, modulus maximum, and energy are chosen as the criteria to detect parallel arc fault. And finally, a mixed criterion is proposed to overcome the shortcomings of the above-mentioned criteria and its reliability is verified by experiments. It provides a theoretical basis for the detection of the parallel arc fault in the PV system.