System and method for controlling a vehicle having an electric heater

• US 9,260,103 B2
• Filed: 03/12/2013
• Issued: 02/16/2016
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Porras, Angel Fernando, Treharne, William David
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): GOLDMAN, RICHARD A
• Application Number:
  US13/795,664
• Publication Number:
  US 20140114515A1
• Time in Patent Office: 1,071 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B60H 1/00385 for vehicles having an electrical drive, e.g. hybrid or fuel cell
• CPC Class Codes: B60H 1/2218 controlling the operation of electric heaters
• CPC Class Codes: B60H 2001/2253 related to an operational state of the vehicle or a vehicle component
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 20/20 Control strategies involving selection of hybrid configuration, e.g. selection between series or parallel configuration
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2050/0075 Automatic parameter input, automatic initialising or calibrating means
• CPC Class Codes: B60W 2556/10 Historical data
• CPC Class Codes: F02D 29/02 : peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

A system and method for operating an electric heater to determine heater functionality is based on actual heater power consumption relative to expected heater power consumption during operating conditions where electrical power consumption by other system components can be accurately estimated. One or more components, including a second heating source, may be controlled based on the heater functionality. The system may include a hybrid vehicle having an engine, an electric heater and heater core, a valve positioned to route coolant through the engine and/or the electric heater, and a controller configured to store a diagnostic code and/or start the engine when the electric heater is commanded on and when the actual energy consumption of the electric heater is below a corresponding threshold.

Claims

1. A method for controlling a hybrid vehicle having an engine and an electric heater, comprising:

estimating an actual energy consumption, using a controller, of the electric heater in response to receipt of a heat request, the actual energy consumption being based on an actual power consumption of the electric heater over a predetermined period of time, wherein the actual power consumption is based on a measured total vehicle power consumption adjusted by subtracting power consumed by all vehicle components using electrical power other than the electric heater;

comparing the actual energy consumption of the electric heater with a corresponding threshold using the controller; and

starting the engine, using the controller, when the actual energy consumption is below the corresponding threshold.

2. The method of claim 1, wherein the measured total vehicle power consumption is based on power supplied by a traction battery.

3. The method of claim 1, wherein vehicle components include a DC/DC converter, air conditioning compressor or an inverter system controller.

4. The method of claim 1, wherein the actual energy consumption is estimated after the electric heater has achieved a minimum power upon being commanded on.

5. The method of claim 1, wherein the corresponding threshold is based on an expected electric heater power consumption, integrated over the predetermined period of time, adjusted for a predetermined percentage of deviation.

6. The method of claim 5, wherein the expected electric heater power consumption is estimated from coolant temperature and current electric heater duty cycle.

7. The method of claim 1, wherein the actual energy consumption of the electric heater is compared with the corresponding threshold after entry conditions have been met, the entry conditions including at least one of the following:

a sensor configured to measure temperature of coolant exiting the electric heater is operational,

a pump configured to force coolant through an electric-only heating loop is operational,

a valve configured to selectively route coolant through at least one of the engine and the electric heater is operational,

vehicle speed is zero, and

the engine is off.

8. A method for controlling a hybrid vehicle having an engine and an electric heater, comprising:

commanding the electric heater on; and

starting the engine in response to an actual electric heater power consumption, based on measured total vehicle power consumption adjusted by subtracting power consumed by all vehicle components using electrical power other than the electric heater, being below a corresponding threshold.

9. The method of claim 8, wherein the actual electric heater power consumption is averaged over a predetermined interval of time.

10. The method of claim 8, wherein the actual electric heater power consumption is based on an instantaneous measurement of power consumption.

11. The method of claim 8, wherein the actual electric heater power consumption is integrated over a predetermined interval of time.

12. The method of claim 8, further comprising:

storing a diagnostic code when the actual electric heater power consumption is below the corresponding threshold indicating inoperability of the electric heater.

13. The method of claim 8, further comprising:

controlling a valve to selectively route coolant from the engine to a heater core to heat the vehicle when the actual electric heater power consumption is below the corresponding threshold.

14. A hybrid vehicle, comprising:

an engine;

an electric heater;

a heater core;

a valve positioned to route coolant through at least one of the engine and the electric heater to the heater core; and

a controller configured to start the engine to provide heat to the vehicle in response to the electric heater being commanded on and an actual electric heater power consumption, based on a measured total vehicle power consumption adjusted by subtracting power consumed by all other vehicle components using electrical power other than the electric heater, being below a corresponding threshold.

15. The hybrid vehicle of claim 14, wherein the actual electric heater power consumption is averaged over a predetermined interval of time.

16. The hybrid vehicle of claim 14, wherein the actual electric heater power consumption is based on an instantaneous measurement of power consumption.

17. The hybrid vehicle of claim 14, wherein the actual electric heater power consumption is integrated over a predetermined interval of time.

18. The hybrid vehicle of claim 14, further comprising a sensor configured to measure a temperature of coolant exiting the electric heater, wherein the temperature is used by the controller, in combination with current duty cycle, to estimate an expected power consumption of the electric heater, and wherein the corresponding threshold is based on the expected power consumption adjusted for allowable deviation.

19. The hybrid vehicle of claim 14, wherein the measured total vehicle power consumption is based on power supplied by a traction battery.

20. The hybrid vehicle of claim 14, wherein vehicle components include a DC/DC converter, air conditioning compressor or an inverter system controller.