Wavelet Based Enhanced Fault Detection Scheme for A Distribution System Embedded with Electric Vehicle Charging Station

Nowadays, Electric Vehicle (EV) technology is gaining pace with the modern requirement of limiting the fossil fuel consumption and greenhouse gas emission. However, such EVs require charging stations which are to be installed in the Distribution System (DS) and may be connected with different converter topologies as well as control techniques. Further, the current during the fault may be modulated due to the adopted control and protection circuits of the converters. When the fault occurs in the charging station, in case the fault is not cleared from the charging station, the backup should be provided by the detection of fault using the conventional protection technique: over current relay. Since the fault current is limited at the charging station, the backup relay may fail to detect the fault, which relies on change in current. Hence, development of a new technique is inevitable for fault detection if the DS is connected to the charging station. In this work, the wavelet transform-based scheme is proposed to enhance fault detection in the presence of battery charging station in DS. A charging station connected to 11 kV, 50 Hz AC substation is simulated in MATLAB/SIMULINK and results show the proposed method efficiently detects the fault in the DS.