Fault Considerations of Non-Isolated Electric Vehicle Chargers with a Mutual DC Supply

This work focuses on the differing fault behavior of non-isolated electric vehicle chargers that are being sourced by a mutual DC grid, compared to an isolated system. Therefore a simulation model for a small DC grid is created. Evaluated fault scenarios are earth faults on the vehicle side as well as the grid side, and parallel faults between the positive conductors of two EVs. The resulting currents and voltages are compared to safety requirements with regard to current standards.