Vehicle heating system and method

• US 9,822,752 B2
• Filed: 05/19/2014
• Issued: 11/21/2017
• Est. Priority Date: 05/19/2014
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Ragazzi, Franco, Leone, Thomas G.
• Primary Examiner(s): Amin, Bhavesh V
• Application Number:
  US14/281,753
• Publication Number:
  US 20150330351A1
• Time in Patent Office: 1,282 Days
• CPC Class Codes: B60H 1/00314 Arrangements permitting a rapid heating of the heating liquid B60H1/00492, B60H1/03 take precedence; aiding engine start by heating of engine coolants F02N19/10
• CPC Class Codes: B60H 1/00921 where the flow direction of the refrigerant does not change and there is an extra subcondenser, e.g. in an air duct
• CPC Class Codes: B60H 2001/00928 comprising a secondary circuit
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: F01M 5/021 by heating
• CPC Class Codes: F01P 11/20 concerning atmospheric freezing conditions, e.g. automatically draining or heating during frosty weather
• CPC Class Codes: F02M 31/16 Other apparatus for heating fuel
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: F02N 19/04 by heating of fluids used in engines
• CPC Class Codes: F02N 19/10 by heating of engine coolants
• CPC Class Codes: F02N 2200/023 Engine temperature
• CPC Class Codes: F02N 2200/122 Atmospheric temperature
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors

Abstract

Methods and system for providing heat to a vehicle are presented. In one example, a heat pump supplies thermal energy to an engine to reduce engine emissions during engine starting. Further, heating the engine via the heat pump may also reduce engine friction at colder ambient temperatures where oil viscosity may be increased.

Claims

1. A method for heating a vehicle, comprising:

selectively operating a vehicle vapor compression heat pump system of the vehicle when the vehicle is electrically coupled to a stationary electrical power grid; and

via activating at least the vehicle vapor compression heat pump system, transferring heat from a passenger cabin to a refrigerant in a heat pump system via an interior heat exchanger, transferring heat from the refrigerant to glycol coolant in a coolant system via an intermediate heat exchanger, and transferring heat from the glycol coolant to an engine in response to the vehicle being electrically coupled to the stationary electrical power grid.

2. The method of claim 1, further comprising activating the vehicle vapor compression heat pump system in response to an amount of time to heat the engine to a threshold temperature, the amount of time based on ambient temperature and engine temperature, and not providing the heat until an engine temperature is less than a first threshold temperature, where the vehicle vapor compression heat pump system provides the heat via compressing the refrigerant and transferring heat from the refrigerant to engine coolant in the coolant system, and where the refrigerant is expanded via an expansion valve in the heat pump system, and wherein a pump pumps the glycol coolant while the vapor compression heat pump system is activated.

3. The method of claim 2, further comprising not providing heat to the engine in response to engine temperature being greater than a second threshold temperature, and where the heat pump system includes an evaporator and a condenser.

4. The method of claim 1, where selectively operating the vehicle vapor compression heat pump system includes not operating the vehicle vapor compression heat pump system until a predetermined time before a predetermined trip departure time, and further comprising flowing the glycol coolant through the engine and bypassing glycol coolant flow around a radiator in the coolant system which transfers thermal energy to air surrounding the vehicle via a valve while heating the engine via the vehicle vapor compression heat pump system.

5. The method of claim 4, where the predetermined time is based on ambient temperature and engine temperature.

6. The method of claim 4, where transferring heat from the glycol coolant to the engine includes adjusting engine temperature to a desired temperature, and further comprising anticipating engine starting based on battery state of charge, and starting the vehicle vapor compression heat pump system before the engine is started based on the anticipated engine starting.

7. The method of claim 1, further comprising determining a desired heat pump system operating mode via a heat pump system control module in the vehicle in response to the vehicle being electrically coupled to the stationary electrical power grid, and

responsive to the heat pump system being commanded in a cooling mode and engine temperature not increasing as is desired because only a small amount of heat is being extracted from the passenger cabin, transitioning the heat pump system temporarily to a series dehumidification mode where heat is absorbed by refrigerant from both ambient air and the passenger cabin, and where a passenger cabin ventilation system is adjusted into a recirculation mode where cabin air is not mixed with outside fresh air.

8. A method for heating a vehicle, comprising:

selectively operating a heat pump system of the vehicle via activating a compressor of the heat pump system when an engine of the vehicle is stopped; and

via activating at least the vehicle heat pump system, transferring heat from a passenger cabin to refrigerant in the heat pump system via an interior heat exchanger, transferring heat from the refrigerant to glycol coolant in a coolant system via an intermediate heat exchanger, and transferring heat from the glycol coolant to the engine in response to anticipated starting of the engine based on battery state of charge, and starting the vehicle heat pump system before the engine is started based on the anticipated engine starting.

9. The method of claim 8, wherein transferring heat from the passenger cabin to the refrigerant cools the passenger cabin, and wherein transferring heat from the passenger cabin is in response to the vehicle being electrically coupled to a stationary electrical power grid.

10. The method of claim 8, where an electric machine propels the vehicle when the engine is stopped, and where the heat pump system is a vapor compression heat pump system, and further comprising flowing the glycol coolant through the engine and bypassing glycol coolant flow around a radiator in the coolant system which transfers thermal energy to air surrounding the vehicle via a valve while heating the engine via the vapor compression heat pump system.

11. The method of claim 8, where transferring heat from the glycol coolant to the engine includes increasing engine temperature to a threshold temperature and holding the engine at the threshold temperature, and responsive to the heat pump system being commanded in a cooling mode and engine temperature not increasing as is desired because only a small amount of heat is being extracted from the passenger cabin, transitioning the heat pump system temporarily to a series dehumidification mode.

12. The method of claim 8, further comprising not providing heat to the engine via the heat pump system in response to a temperature of a passenger cabin not being within a threshold temperature of a desired passenger cabin temperature.

13. The method of claim 8, further comprising heating the passenger cabin to a desired temperature via the vehicle heat pump system when the engine of the vehicle is stopped.

14. The method of claim 8, further comprising not providing heat to the engine via the vehicle heat pump system when engine temperature is greater than a threshold temperature.

15. A vehicle system, comprising:

an engine;

a climate control system with a coolant subsystem, a heat pump subsystem, and a ventilation subsystem, the coolant subsystem including a heater core and a radiator, the coolant subsystem and the heat pump subsystem including an intermediate heat exchanger providing thermal communication between the heat pump subsystem and the coolant subsystem, the radiator separate from the intermediate heat exchanger; and

a controller including executable instructions stored in non-transitory memory for supplying thermal energy via the intermediate heat exchanger to engine coolant via operating the heat pump subsystem in a cooling mode and to transition to a series dehumidification mode in response to a temperature of the engine, and further to supply the thermal energy by operating the intermediate heat exchanger as a condenser while bypassing the heater core.

16. The vehicle system of claim 15, further comprising an electric motor and additional instructions for supplying current from the electric motor to the heat pump subsystem in response to a regenerative current being greater than a current accepted by a battery to charge the battery.

17. The vehicle system of claim 16, further comprising additional instructions for supplying current from the electric motor to the heat pump subsystem in response to a battery state of charge being greater than a threshold.

18. The vehicle system of claim 15, further comprising additional instructions for adjusting the climate control system into a recirculation mode in response to the temperature of the engine, where in the recirculation mode, an air intake of a passenger compartment climate control system receives more than a predetermined amount of air from inside a passenger compartment.

19. The vehicle system of claim 16, further comprising the battery and instructions for activating the heat pump subsystem in response to current in excess of a battery charge current provided by the electric motor.

20. The vehicle system of claim 19, further comprising additional instructions for supplying electric current to the heat pump subsystem in response to a battery state of charge being less than a threshold and in response to the vehicle not being in a regenerative braking mode.