Abstract: A power supply system for converting and/or isolating charging power supplied to a vehicle charging system (VCS) within a battery operated vehicle. An isolation transformer allows electric isolation and/or voltage conversion between a primary power source (PPS) and the VCS. A terminal(s) of the transformer primary side is connectable to the PPS, and a terminal(s) of the transformer secondary side is connectable to the VCS. An EVSE control device is electrically connectable to the VCS. A data communication line connected to the EVSE control device and connectable to the VCS allows transmission of control signals to the VCS, monitoring coupling between secondary side and the VCS, and monitoring at least one parameter related to the charging status of the VCS during charging. The isolation transformer is a solid state transformer, and the isolation transformer and the EVSE control device constitutes an integrated unit, i.e., physically arranged in a common unit.