Abstract: A battery self-heating method includes: obtaining a temperature and a state of charge of a battery; determining a current amplitude and a frequency during self-heating of the battery according to the temperature and the state of charge; and performing a closed-loop control on a battery self-heating device according to the current amplitude and the frequency, so as to self-heat the battery. Determining a current amplitude and a frequency may include obtaining a voltage and a voltage threshold of a bus side of the device when the battery enters a self-heating mode; determining a duty ratio threshold according to the voltage and the voltage threshold; determining a correspondence between the current amplitude and the frequency according to the duty ratio threshold; and determining the current amplitude and the frequency according to the temperature and the state of charge, based on the correspondence between the current amplitude and the frequency.

Abstract: A circuit and method for providing multi-mode power to a vehicle load may include first and second voltage sources, main positive and main negative relays, and first, second, and third relays. The main positive relay may have a second side connected to a first side of the load, and the main negative relay may have a second side connected to a second side of the load. A first side of the second relay may be connected to a positive side of the first voltage source, and a second side of the second relay to a positive side of the second voltage source and a first side of the main positive relay. A first side of the third relay may be connected to a negative side of the second voltage source, and a second side of the third relay to a first side of the main negative relay.

Abstract: A circuit and method for providing multi-mode power to a vehicle load may include first and second voltage sources, main positive and main negative relays, and first, second, and third relays. The main positive relay may have a second side connected to a first side of the load, and the main negative relay may have a second side connected to a second side of the load. A first side of the second relay may be connected to a positive side of the first voltage source, and a second side of the second relay to a positive side of the second voltage source and a first side of the main positive relay. A first side of the third relay may be connected to a negative side of the second voltage source, and a second side of the third relay to a first side of the main negative relay.

Abstract: An on-board charger is provided with a bulk capacitor adapted to couple to a vehicle traction battery and a relay for receiving electrical power from an external power supply and to pre-charge the bulk capacitor. A power factor correction (PFC) circuit is connected between the bulk capacitor and the relay. The PFC circuit includes a switch that is adjustable between an on-position and an off-position. The switch enables current flow from the relay to the bulk capacitor in the off-position. A snubber circuit is coupled to the switch to damp a transient voltage present at the switch during a transition from the on-position to the off-position. A processor is programmed to control the switch.

Abstract: An on-board charger is provided with a bulk capacitor adapted to couple to a vehicle traction battery and a relay for receiving electrical power from an external power supply and to pre-charge the bulk capacitor. A power factor correction (PFC) circuit is connected between the bulk capacitor and the relay. The PFC circuit includes a switch that is adjustable between an on-position and an off-position. The switch enables current flow from the relay to the bulk capacitor in the off-position. A snubber circuit is coupled to the switch to damp a transient voltage present at the switch during a transition from the on-position to the off-position. A processor is programmed to control the switch.