Amplitude-Phase-Characteristics-Based Fault Phase Detection Method for Grounding Fault in Distribution Network

The fault phase detection (FPD) of single-line-to-ground fault (SLGF) is important for active arc suppression devices (AASD), but it is challenging when considering asymmetrical line parameters and different neutral grounding types. To improve the reliability of FPD, this article proposes an FPD method based on the fusion of amplitude and phase angle characteristics. First, when an SLGF occurs, the amplitude and phase angle characteristics of the three-phase source voltage are analyzed. Then, the phase angle of the fault phase source voltage is calculated based on the derived amplitude and phase angle characteristics, which are compared with the measured phase angle of the three-phase source voltage, respectively. According to the FPD criterion, the fault phase can be determined. In addition, an FPD device (FPDD) featuring convenient installation has been designed. The FPD results are sent to AASD, if the fault phase voltage can be effectively suppressed, the FPD results are correct. The proposed method has been experimentally validated on 380 V and 10 kV experimental platforms.