Power Supply System And Vehicle Including The Same

• US 20090067202A1
• Filed: 02/16/2007
• Published: 03/12/2009
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Oyobe, Hichirosai, Yoshida, Hiroshi, Ishikawa, Tetsuhiro, Ichikawa, Shinji, Sawada, Hiroki, Ang, Wanleng
• Granted Patent: US 7,956,489 B2
• Time in Patent Office: Days
• US Class Current: 363/79
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel
• 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 10/72 Electric energy management in electromobility

Abstract

A converter ECU (2) obtains allowable power total value including at least one of discharge allowable power total value ΣWout of discharge allowable power Wout1, Wout2 and charge allowable power total value ΣWin of charge allowable power Win1, Win2. Then, the converter ECU (2) determines which of the allowable power total value and an actual power value is greater, If the actual power value is smaller than the allowable power total value, the converter ECU (2) controls a converter (8-1) such that an input/output voltage value Vh attains a prescribed target voltage value, and at the same time controls a converter (8-2) such that a battery current value Ib2 attains a prescribed target current value.

Claims

1. A power supply system including a plurality of power storage units each configured to be capable of charge/discharge, comprising:

a power line configured to allow supply/reception of electric power between a load device and said power supply system;

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation;

actual power value obtaining means for obtaining, on said power line, an actual value of electric power supplied/received to/from said load device;

first determination means for determining which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and said actual power value, obtained by said actual power value obtaining means, is greater;

first voltage conversion unit control means for setting one of said plurality of voltage conversion units to said voltage control mode and setting remaining voltage conversion unit to said current control mode if said first determination means determines that said actual power value is smaller than said allowable power total value; and

second voltage conversion unit control means for setting said plurality of voltage conversion units to said current control mode if said first determination means determines that said actual power value is equal to or larger than said allowable power total value.

2. The power supply system according to claim 1, further comprising:

electric power fluctuation estimation means for estimating fluctuation of the electric power supplied/received to/from said load device; and

third voltage conversion unit control means for switching the voltage conversion unit, set to said voltage control mode by said first voltage conversion unit control means, to said current control mode when said-electric power fluctuation estimation means estimates that electric power fluctuation is smaller than a prescribed value even if said first determination means determines that said actual power value is smaller than said allowable power total value.

3. The power supply system according to claim 1, further comprising:

second determination means for determining whether charge/discharge restriction is necessary, based on the allowable power of said plurality of power storage units; and

fourth voltage conversion unit control means for setting said plurality of voltage conversion units to said current control mode if said second determination means determines that charge/discharge restriction is necessary.

5. The power supply system according to claim 1, wherein

said current target value in said current control mode is set in accordance with a voltage value of the power storage unit such that said current target value does not exceed the allowable power, for each of said plurality of voltage conversion units.

6. The power supply system according to claim 1, further comprising:

third determination means for determining power margin of said allowable power total value, for said actual power value; and

fifth voltage conversion unit control means for stopping the voltage conversion operation in the voltage conversion unit corresponding to at least one power storage unit out of said plurality of power storage units, if said third determination means determines, in a control operation by said first voltage conversion unit control means, that said power margin is greater than the allowable power of said at least one power storage unit.

4. (canceled)

7. A power supply system including a plurality of power storage units each configured to be capable of charge/discharge, comprising:

a power line configured to allow supply/reception of electric power between a load device and said power supply system;

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line; and

a control device;

wherein

each of said plurality of voltage conversion units is set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation,

said control device obtains, on said power line, an actual value of electric power supplied/received to/from said load device, determines which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and obtained actual power value is greater, and sets one of said plurality of voltage conversion units to said voltage control mode and remaining voltage conversion unit to said current control mode if it is determined that said actual power value is smaller than said allowable power total value, and sets said plurality of voltage conversion units to said current control mode if it is determined that said actual power value is equal to or larger than said allowable power total value.

8. A method of controlling a power supply system including a plurality of power storage units each configured to be capable of charge/discharge, a power line configured to allow supply/reception of electric power between a load device and said power supply system, and a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, comprising the steps of:

obtaining, on said power line, an actual value of the electric power supplied/received to/from said load device;

determining which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and obtained actual power value is greater;

setting one of said plurality of voltage conversion units to said voltage control mode and setting remaining voltage conversion unit to said current control mode if it is determined that said actual power value is smaller than said allowable power total value; and

setting said plurality of voltage conversion units to said current control mode if it is determined that said actual power value is equal to or larger than said allowable power total value.

9. A vehicle comprising:

a power supply system having a plurality of power storage units each configured to be capable of charge/discharge; and

a drive force generation unit generating drive force by receiving electric power supplied from said power supply system; and

said power supply system including

a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system,

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation,

actual power value obtaining means for obtaining, on said power line, an actual value of the electric power supplied/received to/from said drive force generation unit,

first determination means for determining which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and said actual power value, obtained by said actual power value obtaining-means, is greater,

first voltage conversion unit control means for setting one of said plurality of voltage conversion units to said voltage control mode and setting remaining voltage conversion unit to said current control mode if said first determination means determines that said actual power value is smaller than said allowable power total value; and

second voltage conversion unit control means for setting said plurality of voltage conversion units to said current control mode if said first determination means determines that said actual power value is equal to or larger than said allowable power total value.

10. The vehicle according to claim 9, wherein

said drive force generation unit includes

at least one electric power conversion unit configured to be able to convert the electric power supplied from said power supply system, and

at least one rotating electric machine connected to corresponding said electric power conversion unit and configured to be able to generate said drive force.

11. The vehicle according to claim 9, wherein

said power supply system further includes

electric power fluctuation estimation means for estimating fluctuation of the electric power supplied/received to/from said drive force generation unit, and

third voltage conversion unit control means for switching the voltage conversion unit, set to said voltage control mode by said first voltage conversion unit control means, to said current control mode when said electric power fluctuation estimation means estimates that electric power fluctuation is smaller than a prescribed value even if said first determination means determines that said actual power value is smaller than said allowable power total value.

12. The vehicle according to claim 9, wherein

said power supply system further includes

fourth determination means for determining whether charge/discharge restriction is necessary, based on the allowable power of said plurality of power storage units, and

third voltage conversion unit control means for setting said plurality of voltage conversion units to said current control mode if said second determination means determines that charge/discharge restriction is necessary.

14. The vehicle according to claim 9, wherein

said current target value in said current control mode is set in accordance with a voltage value of the power storage unit such that said current target value does not exceed the allowable power, for each of said plurality of voltage conversion units.

15. The vehicle according to claim 9, wherein

said power supply system further includes

third determination means for determining power margin of said allowable power total value, for said actual power value, and

fifth voltage conversion unit control means for stopping the voltage conversion operation in the voltage conversion unit corresponding to at least one power storage unit out of said plurality of power storage units, if said third determination means determines, in a control operation by said first voltage conversion unit control means, that said power margin is greater than the allowable power of said at least one power storage unit.

13. (canceled)

16. A vehicle comprising:

a power supply system having a plurality of power storage units each configured to be capable of charge/discharge; and

a drive force generation unit generating drive force by receiving electric power supplied from said power supply system;

wherein

said power supply system includes

a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system,

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, and

a control device,

each of said plurality of voltage conversion units is set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, and

said control device obtains, on said power line, an actual value of the electric power supplied/received to/from said drive force generation unit, determines which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and obtained actual power value is greater, and sets one of said plurality of voltage conversion units to said voltage control mode and remaining voltage conversion unit to said current control mode if it is determined that said actual power value is smaller than said allowable power total value, and sets said plurality of voltage conversion units to said current control mode if it is determined that said actual power value is equal to or larger than said allowable power total value.

17. A method of controlling a vehicle, said vehicle including a power supply system having a plurality of power storage units each configured to be capable of charge/discharge and a drive force generation unit generating drive force by receiving electric power supplied from said power supply system, said power supply system including a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system and a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, comprising the steps of:

obtaining, on said power line, an actual value of the electric power supplied/received to/from said drive force generation unit;

determining which of an allowable power total value, representing a total value of allowable power of said plurality of power storage units, and obtained actual power value is greater;

setting one of said plurality of voltage conversion units to said voltage control mode and setting remaining voltage conversion unit to said current control mode if it is determined that said actual power value is smaller than said allowable power total value; and

setting said plurality of voltage conversion units to said current control mode if it is determined that said actual power value is equal to or larger than said allowable power total value.

18. A power supply system including a plurality of power storage units each configured to be capable of charge/discharge, comprising:

a power line configured to allow supply/reception of electric power between a load device and said power supply system;

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation,

power storage unit temperature obtaining means for obtaining temperatures of said plurality of power storage units;

temperature determination means for determining whether each of the temperatures of said plurality of power storage units obtained by said power storage unit temperature obtaining means is lower than a corresponding temperature lower limit value;

first mode setting means for setting said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined by said temperature determination means as lower than said temperature lower limit value, to said current control mode, and sets remaining said voltage conversion unit to said voltage control mode; and

second mode setting means for setting said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

20. The power supply system according to claim 18, wherein

said first mode setting means sets solely said voltage conversion unit corresponding to said power storage unit of higher priority to said current control mode, if it is determined that the temperature of all of said plurality of power storage units is lower than corresponding said temperature lower limit value.

21. The power supply system according to claim 18, wherein

said current target value in said current control mode is set in accordance with the obtained temperature of the power storage unit, for each of said plurality of voltage conversion units.

22. The power supply system according to claim 21, wherein

said current target value is decided based on predetermined charge/discharge characteristic indicating correspondence between a current value and a voltage value of the power storage unit in accordance with the temperature of the power storage unit, such that the voltage value of the power storage unit is not lower than a prescribed voltage lower limit value.

19. (canceled)

23. A power supply system including two power storage units each configured to be capable of charge/discharge, comprising:

a power line configured to allow supply/reception of electric power between a load device and said power supply system;

two voltage conversion units provided between said two power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said two voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation;

power storage unit temperature obtaining means for obtaining temperatures of said two power storage units;

temperature determination means for determining whether each of the temperatures of said two power storage units obtained by said power storage unit temperature obtaining means is lower than a corresponding temperature lower limit value;

first mode setting means for setting said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined by said temperature determination means as lower than said temperature lower limit value, to said voltage control mode, and sets the other voltage conversion unit to said current control mode; and

second mode setting means for setting said two voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

24. A power supply system including a plurality of power storage units each configured to be capable of charge/discharge, comprising:

a power line configured to allow supply/reception of electric power between a load device and said power supply system;

a plurality of voltage conversion units provided between said plurality of power storage units and said power line respectively and each performing a voltage conversion operation between corresponding said power storage unit and said power line; and

a control device;

wherein

each of said plurality of voltage conversion units is set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, and

said control device obtains temperatures of said plurality of power storage units, determines whether each of obtained temperatures of said plurality of power storage units is lower than a corresponding temperature lower limit value, and sets one of said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined as lower than said temperature lower limit value, to said current control mode, and sets remaining said-voltage conversion to said voltage control mode, and sets said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

25. A method of controlling a power supply system including a plurality of power storage units each configured to be capable of charge/discharge, a power line configured to allow supply/reception of electric power between a load device and said power supply system, and a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, comprising the steps of:

obtaining temperatures of said plurality of power storage units;

determining whether each of obtained temperatures of said plurality of power storage units is lower than a corresponding temperature lower limit value;

setting one of said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined as lower than said temperature lower limit value, to said current control mode, and setting remaining said voltage conversion to said voltage control mode; and

setting said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

26. A vehicle comprising:

a power supply system having a plurality of power storage units each configured to be capable of charge/discharge; and

a drive force generation unit generating drive force by receiving electric power supplied from said power supply system; and

said power supply system including

a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system,

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation,

power storage unit temperature obtaining means for obtaining temperatures of said plurality of power storage units,

temperature determination means for determining whether each of the temperatures of said plurality of power storage units obtained by said power storage unit temperature obtaining means is lower than a corresponding temperature lower limit value, and

first mode setting means for setting said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined by said temperature determination means as lower than said temperature lower limit value, to said current control mode, and sets remaining said voltage conversion unit to said voltage control mode; and

second mode setting means for setting said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

28. The vehicle according to claim 26, wherein

said first mode setting means sets solely said voltage conversion unit corresponding to said power storage unit of higher priority to said current control mode, if it is determined that the temperature of all of said plurality of power storage units is lower than corresponding said temperature lower limit value.

29. The vehicle according to claim 26, wherein

said current target value in said current control mode is set in accordance with the obtained temperature of the power storage unit, for each of said plurality of voltage conversion units.

30. The vehicle according to claim 29, wherein

said current target value is decided based on predetermined charge/discharge characteristic indicating correspondence between a current value and a voltage value of the power storage unit in accordance with the temperature of the power storage unit, such that the voltage value of the power storage unit is not lower than a prescribed voltage lower limit value.

27. (canceled)

31. A vehicle comprising:

a power supply system having a plurality of power storage units each configured to be capable of charge/discharge; and

a drive force generation unit generating drive force by receiving electric power supplied from said power supply system;

wherein

said power supply system includes

a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system,

a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, and

a control device,

each of said plurality of voltage conversion units is set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion-operation, and

said control device obtains temperatures of said plurality of power storage units, determines whether each of obtained temperatures of said plurality of power storage units is lower than a corresponding temperature lower limit value, and sets one of said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined as lower than said temperature lower limit value, to said current control mode, and sets remaining said voltage conversion to said voltage control mode, and sets said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.

32. A method of controlling a vehicle, said vehicle including a power supply system having a plurality of power storage units each configured to be capable of charge/discharge and a drive force generation unit generating drive force by receiving electric power supplied from said power supply system, said power supply system including a power line configured to allow supply/reception of electric power between said drive force generation unit and said power supply system and a plurality of voltage conversion units provided between said plurality of power storage units and said power line and each performing a voltage conversion operation between corresponding said power storage unit and said power line, each of said plurality of voltage conversion units being set to any one of a voltage control mode in which a voltage value of said power line is controlled to attain a voltage target value and a current control mode in which a current value of corresponding said power storage unit is controlled to attain a current target value, to perform said voltage conversion operation, comprising the steps of:

obtaining temperatures of said plurality of power storage units;

determining whether each of obtained temperatures of said plurality of power storage units is lower than a corresponding temperature lower limit value;

setting one of said voltage conversion unit, corresponding to said power storage unit of which temperature has been determined as lower than said temperature lower limit value, to said current control mode, and setting remaining said voltage conversion to said voltage control mode; and

setting said plurality of voltage conversion unit to either of said current control mode or said voltage control mode, if it is determined that said power storage unit of which temperature is lower than said temperature lower limit value does not exist.