The present invention discloses a vehicle charging and emergency power supply
system based on an
electric vehicle and a control method thereof. The vehicle charging and emergency power supply
system comprises a
power battery and a charging loop, and furthermore comprises the components of: a
control unit, an emergency
signal triggering module, a socket current detecting module, a battery electric-amount acquiring module, a discharging loop, a first
relay, a second
relay, a third
relay and a fourth relay; wherein the emergency
signal triggering module, the socket current detecting module, the battery electric-amount acquiring module, the discharging loop, the first relay, the second relay, the third relay and the fourth relay are respectively connected with the
control unit. The
control unit is furthermore connected with the charging loop. The
power battery is connected with the input end of the discharging loop through the third relay. The output end of the discharging loop is connected with an
electric vehicle socket through the first relay. The
electric vehicle socket is connected with the input end of the charging loop through the second relay. The output end of the charging loop is connected with the
power battery through the fourth relay. The control unit controls action of the first relay, the second relay, the third relay and the fourth relay and operation states of the charging loop and the discharging loop according to an acquired
signal. The vehicle charging and emergency power supply
system based on the electric vehicle and the control method thereof have functions of: widening use function of the electric vehicle, and improving applicability of the electric vehicle.