Method for initiating a defrosting process of a heat exhanger of a heat pump of a motor vehicle and a corresponding motor vehicle
A method for initiating a defrosting process of a heat exchanger of a heat pump of a motor vehicle, wherein the heat exchanger and a coolant heat exchanger of a cooling circuit of the motor vehicle are arranged in a common air path, involves determining a coolant outlet temperature of a coolant from the coolant heat exchanger, determining a state of icing of the heat exchanger using the coolant outlet temperature, and initiating a defrosting process of the heat exchanger if icing of the heat exchanger is determined.
1. A method for initiating a defrosting process of a heat exchanger of a heat pump of a motor vehicle, wherein the heat exchanger and a coolant heat exchanger of a cooling circuit of the motor vehicle are arranged in a common air path, comprising:
determining a coolant outlet temperature of a coolant from the coolant heat exchanger of the cooling circuit,
increasing or decreasing the coolant temperature when the coolant temperature corresponds substantially to an ambient temperature
determining a state of icing of the heat exchanger of the heat pump using the coolant outlet temperature, and
initiating a defrosting process of the heat exchanger of the heat pump if icing of the heat exchanger is determined.
2. The method according to claim 1 , wherein the state of icing of the heat exchanger of the heat pump is determined from a change in the coolant outlet temperature.
3. The method according to claim 2 , wherein the change in the coolant outlet temperature is an increase.
4. The method according to claim 1 , further comprising:
determining a coolant inlet temperature of the coolant in the coolant heat exchanger of the cooling circuit, and
determining a coolant temperature difference from the coolant inlet temperature and the coolant outlet temperature, and
wherein the state of icing of the heat exchanger of the heat pump is determined from a change in the coolant temperature difference.
5. The method according to claim 4 , wherein the change in the coolant temperature difference is a decrease.
6. The method according to claim 4 , wherein the coolant temperature is a coolant inlet temperature.
7. The method according to claim 1 ,
further comprising determining a coolant volume flow and/or a performance of a coolant pump of the cooling circuit,
wherein the coolant volume flow and/or the performance of the coolant pump is used to determine the state of icing of the heat exchanger.
8. The method according to claim 1 , wherein the cooling circuit is operated for the determination of the state of icing, and the cooling circuit is operated over a specific period of time for the determination of the state of icing.
9. The method according to claim 8 , wherein the specific period of time is less than 30 seconds.
10. The method according to claim 1 , wherein a parameter is used to determine the state of icing, and wherein the parameter is an indicator of a current relative air speed of the ambient air in relation to the motor vehicle.
11. The method according to claim 10 , wherein the parameter is the current driving speed of the motor vehicle, the wind speed and/or the wind direction.
12. The method according to claim 10 , wherein the parameter is a distance signa.
13. The method according to claim 12 , wherein the distance signal is the distance value is of the motor vehicle in relation to a vehicle traveling in front of the motor vehicle.
14. The method according to claim 10 , wherein the parameter is a vehicle position.
15. The method according to claim 14 , wherein the vehicle position is a position of the motor vehicle in a road tunnel, in a valley, or in a street canyon.
16. The method according to claim 1 , wherein the motor vehicle is an electric vehicle, a battery-electric vehicle or a hybrid electric vehicle.
17. A motor vehicle, comprising:
a device for defrosting a heat exchanger of a heat pump of the motor vehicle, wherein the heat exchanger and a coolant heat exchanger of a cooling circuit of the motor vehicle are arranged in a common air path,
wherein the device has a computing unit that is configured to carry out a method comprising:
increasing or decreasing the coolant temperature when the coolant temperature corresponds substantially to an ambient temperature
determining a coolant outlet temperature of a coolant from the coolant heat exchanger of the cooling circuit,
determining a state of icing of the heat exchanger of the heat pump using the coolant outlet temperature, and
initiating a defrosting process of the heat exchanger of the heat pump if icing of the heat exchanger is determined.