Vehicle propulsion system having an energy storage system and optimized method of controlling operation thereof

• US 10,081,350 B2
• Filed: 07/13/2016
• Issued: 09/25/2018
• Est. Priority Date: 08/19/2014
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Zhou, Zhi
• Primary Examiner(s): Shaawat, Mussa A
• Assistant Examiner(s): Jha, Abdhesh K
• Application Number:
  US15/208,777
• Publication Number:
  US 20160318503A1
• Time in Patent Office: 804 Days
• Field of Search: None
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/427 Voltage
• CPC Class Codes: B60L 2240/527 Voltage
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2260/42 by adaptive correction
• CPC Class Codes: B60L 2260/54 Energy consumption estimation
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/90 using propulsion power supplied by specific means not covered by groups B60L50/10 - B60L50/50, e.g. by direct conversion of thermal nuclear energy into electricity
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/21 : having the same nominal voltage
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• 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 20/10 : Controlling the power contribution of each of the prime movers to meet required power demand
• 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 20/19 : for achieving enhanced acceleration
• CPC Class Codes: B60W 2510/0666 : Engine power
• CPC Class Codes: B60W 2510/085 : Power
• CPC Class Codes: B60W 2510/244 : Charge state
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: B60W 2710/086 : Power
• CPC Class Codes: B60W 2710/242 : for electrical energy
• CPC Class Codes: H02J 2310/48 : for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/0048 : Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/005 : Detection of state of health [SOH]
• CPC Class Codes: H02J 7/1423 : with multiple batteries
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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 vehicle propulsion system includes a plurality of power sources coupled to a final drive of the vehicle propulsion system. A controller is programmed to determine a desired power demand from the power sources and operate a number of the power sources to produce the desired power demand. The controller identifies a least efficient power source of the power sources and controls the least efficient power source to produce power at an optimum operating point of the least efficient power source. The controller also identifies a power output of the least efficient power source corresponding to the optimum operating point, compares the power output of the least efficient power source to the desired power demand, identifies a remaining power demand from the comparison, and controls another power source to produce the remaining power demand.

Claims

1. A vehicle propulsion system comprising:

a plurality of power sources coupled to a load of the vehicle propulsion system, wherein the plurality of power sources comprises;

an engine; and

a plurality of batteries; and

a controller configured with a database comprising one or more efficiency contour maps for the plurality of power sources, the controller programmed to;

determine a power demand sufficient to operate the load; and

operate the plurality of power sources to produce the power demand, wherein operating the plurality of power sources comprises;

monitoring the speed and torque of the engine to determine an operating point relative to a point of maximum efficiency on the efficiency contour map of the engine;

monitoring the internal resistances of the plurality of batteries to determine the most efficient battery;

operating the engine to produce power at the operating point relative to the point of maximum efficiency;

comparing the power output of the engine to the power demand to identify a remaining power demand from the comparison; and

controlling the plurality of batteries to produce the remaining power demand by supplementing power from the most efficient battery.

2. The vehicle propulsion system of claim 1, wherein the plurality of batteries comprises:

a high-specific energy battery; and

a high-specific power battery.

3. The vehicle propulsion system of claim 2, wherein the high-specific energy battery supplements power if vehicle speed remains substantially constant.

4. The vehicle propulsion system of claim 2, wherein the high-specific power battery supplements power if the vehicle is substantially accelerating.

5. The vehicle propulsion system of claim 1, wherein the engine is an internal combustion engine.

6. The vehicle propulsion system of claim 1, wherein the load further comprises an electromechanical device coupled to an inverter.

7. The vehicle propulsion system of claim 1, further comprising a DC/DC converter coupled to at least one of the plurality of batteries.

8. The vehicle propulsion system of claim 1, wherein the controller is further programmed to monitor the state of charge (SOC) of each battery to determine the most efficient battery.

9. A vehicle comprising:

a plurality of power sources comprising;

an engine; and

a plurality of batteries;

a load coupled to the plurality of power sources; and

a controller configured with a database comprising one or more efficiency contour maps for the plurality of power sources, the controller programmed to;

determine a power demand sufficient to operate the load; and

operate the plurality of power sources to produce the power demand, wherein operating the plurality of power sources comprises;

monitoring the speed and torque of the engine to determine an operating point relative to a point of maximum efficiency on the efficiency contour map of the engine;

monitoring the internal resistances of the plurality of batteries to determine the most efficient battery;

operating the engine to produce power at the operating point relative to the point of maximum efficiency;

comparing the power output of the engine to the power demand to identify a remaining power demand from the comparison; and

controlling the plurality of batteries to produce the remaining power demand by supplementing power from the most efficient battery.

10. The vehicle of claim 9, wherein the plurality of batteries comprises:

a high-specific energy battery; and

a high-specific power battery.

11. The vehicle of claim 10, wherein the high-specific energy battery supplements power if vehicle speed remains substantially constant.

12. The vehicle of claim 10, wherein the high-specific power battery supplements power if the vehicle is substantially accelerating.

13. The vehicle of claim 9, wherein the engine is an internal combustion engine.

14. The vehicle of claim 9, wherein the load further comprises an electric motor coupled to an inverter.

15. The vehicle of claim 9, further comprising a DC/DC converter coupled to at least one of the plurality of batteries.

16. The vehicle of claim 9, wherein the controller is further programmed to monitor the state of charge (SOC) of each battery to determine the most efficient battery.

17. A control system for a vehicle comprising an engine, a load, and a plurality of batteries, the control system comprising a controller configured with a database comprising one or more efficiency contour maps for the engine, the control system programmed to:

determine a power demand sufficient to operate the load; and

operate the engine and plurality of batteries to produce the power demand, wherein operating the engine and plurality of batteries comprises;

monitoring the speed and torque of the engine to determine an operating point relative to a point of maximum efficiency on the efficiency contour map of the engine;

monitoring the internal resistances of the plurality of batteries to determine the most efficient battery;

operating the engine to produce power at the operating point relative to the point of maximum efficiency;

comparing the power output of the engine to the power demand to identify a remaining power demand from the comparison; and

controlling the plurality of batteries to produce the remaining power demand by supplementing power from the most efficient battery.

18. The control system of claim 17, wherein the plurality of batteries comprises:

a high-specific energy battery; and

a high-specific power battery.

19. The control system of claim 18, wherein the high-specific energy battery supplements power if vehicle speed remains substantially constant.

20. The control system of claim 18, wherein the high-specific power battery supplements power if the vehicle is substantially accelerating.