Advanced electronic circuit breaker techniques for the use in electric vehicle charging stations

For a charging process of an electric vehicle it is important that the process runs safely from the view of the electric site. For this reason in this paper advanced electronic circuit breaker techniques are presented, optimised for the use in electric vehicle charging stations. In doing so the focus lies on the continuous monitoring of the charging process related to the temporal course of the voltage and current readings. Therefore especially algorithms for the detection of the steady state are proposed, which are to be applied at the beginning of charging processes. Several trigger mechanisms for the circuit breaker have to be implemented on an FPGA board, which amongst other things does the signal processing for energy measurement purpose, too. In general the usage of an FPGA as a central part of the charging station provides wide flexibility in configuration from various viewpoints. That is why the proposed trigger algorithms for the circuit breakers can be parameterised easily, and if needed changed. By implementing the proposed circuit breaker techniques there are no significant additional costs for the system, because typically all necessary components are available within an electric vehicle charging station.