The Resistive Ground Fault of PWM Voltage Inverter In The EV Charging Station

Abstract

During the direct touch of the inverter output voltage, the nonsinusoidal ground currents with a basic harmonic frequency between 1.5 kHz and 16 kHz, flow via a human’s body. Here was proved that Residual Current Device (RCD) type AC/IΔn = 30 mA does not switch off the power supply when a ground current with a value of about some hundred milliamps occurs. Because RCDs do not disconnect the power supply, the touch on the inverter’s voltage is dangerous to the health and life. For the authors, RCD usage in Voltage Frequency Converters is not a good engineer practice. The article presents tests of RCD operation in the event of a ground fault during EV battery charging.