Electrified vehicle with inverter controlled to heat traction battery
A system for an electrified vehicle, such as a battery electric vehicle (BEV), includes an inverter and a controller. The inverter is configured to drive a traction motor with electrical power from a traction battery, such as a lithium ion phosphate (LFP) traction battery, according to a configuration of a power switch (e.g., IBGT or MOSFET) of the inverter. The system further includes a controller configured to control a variable gate driver resistance for the power switch in a closed loop fashion to achieve a target temperature of the inverter. The system may further include a heating coolant loop for transferring heat generated by the inverter to the traction battery to warm the traction battery. The controller may be further configured to further control a switching frequency of the power switch in the closed loop fashion to achieve the target temperature of the inverter.
1. A system comprising:
an inverter configured to drive a traction motor with electrical power from a traction battery according to a configuration of a power switch of the inverter; and
a controller configured to control a variable gate driver resistance for the power switch in a closed loop fashion to achieve a target temperature of the inverter.
2. The system of claim 1 wherein:
the controller increases the gate driver resistance to increase an actual temperature of the inverter.
3. The system of claim 2 wherein:
the controller decreases the gate driver resistance to decrease the actual temperature of the inverter.
4. The system of claim 1 further comprising:
a heating coolant loop for transferring heat generated by the inverter to the traction battery to warm the traction battery.
5. The system of claim 1 wherein:
the target temperature of the inverter depends on a target temperature of the traction battery.
6. The system of claim 1 wherein:
the controller is further configured to further control a switching frequency of the power switch in the closed loop fashion to achieve the target temperature of the inverter.
7. The system of claim 6 wherein:
the controller increases the switching frequency to increase an actual temperature of the inverter.
8. The system of claim 7 wherein:
the controller decreases the switching frequency to decrease the actual temperature of the inverter.
9. The system of claim 1 wherein:
the power switch is either an insulated-gate bipolar transistor (IGBT) power switch or a metal-oxide-semiconductor field-effect transistor (MOSFET) transistor.
10. The system of claim 1 wherein:
the inverter includes a plurality of power switches and is configured to drive the traction motor with electrical power from the traction battery according to a configuration of the power switches; and
the controller is further configured to control a variable gate driver resistance for each of the power switches in the closed loop fashion to achieve the target temperature of the inverter.
11. The system of claim 1 wherein:
a turn-on time and a turn-off time of the power switch depend on the gate driver resistance.
12. A method for use with a power electronics module configured to drive a traction motor with electrical power from a traction battery according to a configuration of a power switch of the power electronics module, the method comprising:
setting a gate driver resistance for the power switch according to a difference between an actual temperature of the traction battery and a desired temperature of the traction battery;
controlling the power switch with the gate driver resistance to thereby cause the power electronics module to generate an amount of heat dependent on the gate driver resistance; and
transferring at least some of the heat generated by the power electronics module to the traction battery to warm the traction battery.
13. The method of claim 12 further comprising:
setting a switching frequency for the power switch according to the difference between the actual temperature of the traction battery and the desired temperature of the traction battery;
controlling the power switch further with the switching frequency to thereby cause the power electronics module to generate an additional amount of heat dependent on the switching frequency; and
transferring at least some of the additional heat generated by the power electronics module to the traction battery to warm the traction battery.
14. The method of claim 12 wherein:
the power electronics module is an inverter.
15. The method of claim 14 wherein:
the traction battery is a lithium ion phosphate (LFP) traction battery.
16. An electrified vehicle comprising:
a traction battery;
a traction motor;
a power electronics module configured to drive the traction motor with electrical power from the traction battery according to a configuration of a power switch of the power electronics module;
a controller configured to set a gate driver resistance for the power switch according to a difference between an actual temperature of the traction battery and a desired temperature of the traction battery and to control the power switch with the gate driver resistance to thereby cause the power electronics module to generate an amount of heat dependent on the gate driver resistance; and
a heating coolant loop configured to transfer at least some of the heat generated by the power electronics module to the traction battery to warm the traction battery.
17. The electrified vehicle of claim 16 wherein:
the controller is further configured to set a switching frequency for the power switch according to the difference between the actual temperature of the traction battery and the desired temperature of the traction battery and to control the power switch further with the switching frequency to thereby cause the power electronics module to generate an additional amount of heat dependent on the switching frequency; and
the heating coolant loop is further configured to transfer at least some of the additional heat generated by the power electronics module to the traction battery to warm the traction battery.
18. The electrified vehicle of claim 16 wherein:
the power electronics module is an inverter.
19. The electrified vehicle of claim 16 wherein:
the traction battery is a lithium ion phosphate (LFP) traction battery.
20. The electrified vehicle of claim 16 further comprising:
a passenger cabin; and
wherein at least some of the heat generated by the power electronics module is used to warm the passenger cabin.