Safety supervisory module of an electric vehicle charging station

摘要

A safety supervisory module (SSM) of an electric vehicle charging station that controls flow of current from the electric vehicle charging station to an electric vehicle. The SSM includes a set of two or more processors to control operation of a contactor control circuitry of the SSM to open and close a set of contacts of a set of power supply lines to control flow of current from the charging station to an electric vehicle. Each processor independently determines whether an unsafe condition exists and asserts a relay enable signal to the contactor control circuitry only when an unsafe condition does not exist. The contactor control circuitry generates a current to energize a relay to close the set of contacts responsive to the relay enable signal being asserted by each and every processor of the set of processors, and inhibits closure of the set of contacts or opens the set of contacts to prevent electricity from flowing between the charging station and an electric vehicle when any of the set of processors is not asserting the relay enable signal.