US Patent 10046661 Detection of on-board charger connection to electric vehicle supply equipment

Electric and plug-in hybrid vehicles connect to Electric Vehicle Supply Equipment (EVSE) to recharge a traction battery. Existing standards define the signal interface between the vehicle and EVSE including control pilot and proximity detect signals. The vehicle may use the status of these signals to detect when a connection is established with EVSE. The vehicle may indicate a connection when the signals provide conflicting statuses. The vehicle may prevent driving off and permit charging in the event of a proximity detect signal indicating a state of engagement other than connected as long as a valid control pilot signal is present. The status of the control pilot signal may be utilized to prevent drive-off and permit charging.