POWER SUPPLY SYSTEM, TRANSPORTATION DEVICE, AND POWER TRANSMISSION METHOD

• US 20170155351A1
• Filed: 11/21/2016
• Published: 06/01/2017
• Est. Priority Date: 11/28/2015
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: TAKIZAWA, Daijiro, OGUMA, Hirokazu
• Granted Patent: US 10,581,362 B2
• Time in Patent Office: Days
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• 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 58/20 having different nominal voltages
• CPC Class Codes: B60L 7/16 for vehicles comprising converters between the power source and the motor
• CPC Class Codes: H02M 7/44 by static converters
• CPC Class Codes: H02P 27/08 with pulse width modulation
• CPC Class Codes: H02P 27/14 with three or more levels of voltage
• CPC Class Codes: H02P 3/14 by regenerative braking
• 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 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A power supply system includes a first energy storage, a second energy storage, a power transmission circuit, and circuitry. The first energy storage outputs first output power to an electric load. The second energy storage outputs second output power to the electric load. The circuitry is configured to acquire a demand power to be supplied to the electric load. The circuitry is configured to acquire a remaining capacity value indicating remaining capacity in the second energy storage. The circuitry is configured to control the power transmission circuit to change a ratio of the first output power to the second output power to supply the demand power in accordance with the demand power and the remaining capacity value.

Claims

1. A power supply system comprising:

a first energy storage to output first output power to an electric load, the first energy storage having a first power density and a first energy density;

a second energy storage to output second output power to the electric load, the second energy storage having a second power density higher than a first power density and a second energy density lower than the first energy density;

a power transmission circuit connected to the electric load, the first energy storage, and the second energy storage so as to control power transmission among the electric load, the first energy storage, and the second energy storage; and

circuitry configured to

acquire a demand power to be supplied to the electric load;

acquire a remaining capacity value indicating remaining capacity in the second energy storage; and

control the power transmission circuit to change a ratio of the first output power to the second output power to supply the demand power in accordance with the demand power and the remaining capacity value.

2. The power supply system according to claim 1, wherein the circuitry is configured to control the power transmission circuit so that a proportion of powers to be output by the first energy storage and the second energy storage with respect to the demand power are different when the remaining capacity value falls within a high-remaining-capacity area larger than a predetermined first threshold value, when the remaining capacity value falls within a medium-remaining-capacity area in a range from the first threshold value to a predetermined second threshold value smaller than the first threshold value, and when the remaining capacity value falls within a low-remaining-capacity area smaller than the second threshold value.

3. The power supply system according to claim 2, wherein the circuitry is configured to control the power transmission circuit to, when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is smaller than a predetermined A-th threshold value, supply a supplied power corresponding to the demand power only from the second energy storage among the first energy storage and the second energy storage to the electric load.

4. The power supply system according to claim 3, wherein the circuitry is configured to control the power transmission circuit to, when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is larger than the A-th threshold value, supply the supplied power corresponding to the demand power from both the first energy storage and the second energy storage to the electric load.

5. The power supply system according to claim 4, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is larger than the A-th threshold value,

output a supplied power corresponding to the A-th threshold value from the second energy storage, and

output from the first energy storage a supplied power equal to a difference obtained by subtracting the supplied power output from the second energy storage from the supplied power corresponding to the demand power.

6. The power supply system according to claim 2, wherein the circuitry is configured to control the power transmission circuit to

output at least a base supplied power from the first energy storage when the remaining capacity value falls within the medium-remaining-capacity area or the low-remaining-capacity area, and

when the remaining capacity value falls within the medium-remaining-capacity area or the low-remaining-capacity area and when a supplied power corresponding to the demand power is smaller than the base supplied power,

supply a supplied power corresponding to the demand power within the base supplied power from the first energy storage to the electric load, and

charge the second energy storage with a surplus supplied power that is a difference obtained by subtracting the supplied power corresponding to the demand power from the base supplied power.

7. The power supply system according to claim 6, wherein the base supplied power comprises a supplied power set so that a sensitivity of a change in the base supplied power to a change in the demand power is lower than a sensitivity of a change in the surplus supplied power to a change in the demand power.

8. The power supply system according to claim 6, wherein the base supplied power comprises a supplied power set regardless of a value of the demand power.

9. The power supply system according to claim 6, wherein the circuitry is configured to have a function of setting the base supplied power to be variable in accordance with the remaining capacity value.

10. The power supply system according to claim 9, wherein the circuitry is configured to set the base supplied power so that the base supplied power continuously changes in response to a change in the remaining capacity value.

11. The power supply system according to claim 9, wherein the circuitry is configured to set the base supplied power so that the base supplied power increases within at least the medium-remaining-capacity area among the low-remaining-capacity area and the medium-remaining-capacity area as the remaining capacity value decreases.

12. The power supply system according to claim 11, wherein the circuitry is configured to set the base supplied power within the low-remaining-capacity area to a value greater than or equal to the base supplied power within the medium-remaining-capacity area.

13. The power supply system according to claim 11, wherein the circuitry is configured to set the base supplied power within the low-remaining-capacity area to a constant value.

14. The power supply system according to claim 6, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the medium-remaining-capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power and the demand power is smaller than a predetermined B-th threshold value,

output the base supplied power from the first energy storage, and

output from the second energy storage a supplied power equal to a difference obtained by subtracting the base supplied power from the supplied power corresponding to the demand power.

15. The power supply system according to claim 14, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the medium-remaining-capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power and the demand power is larger than the B-th threshold value,

supply the supplied power corresponding to the demand power from both the first energy storage and the second energy storage to the electric load while outputting from the first energy storage a supplied power by which the supplied power corresponding to the demand power is larger than the base supplied power.

16. The power supply system according to claim 15, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the medium-remaining-capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power and the demand power is larger than the B-th threshold value,

output from the second energy storage a supplied power equal to a difference obtained by subtracting the base supplied power from a supplied power corresponding to the B-th threshold value, and

output from the first energy storage a supplied power equal to a difference obtained by subtracting the supplied power output from the second energy storage from the supplied power corresponding to the demand power.

17. The power supply system according to claim 6, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the low-remaining-capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power and the demand power is smaller than a predetermined C-th threshold value,

supply the supplied power corresponding to the demand power only from the first energy storage among the first energy storage and the second energy storage to the electric load.

18. The power supply system according to claim 6, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the low-remaining-capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power and the demand power is larger than a predetermined C-th threshold value,

output a supplied power corresponding to the C-th threshold value from the first energy storage, and

output from the second energy storage a supplied power equal to a difference obtained by subtracting the supplied power output from the first energy storage from the supplied power corresponding to the demand power.

19. The power supply system according to claim 1, wherein the circuitry is configured to control the power transmission circuit so that a proportion of powers to be output by the first energy storage and the second energy storage with respect to the demand power are different when the remaining capacity value falls within a high-remaining-capacity area larger than a predetermined first threshold value and when the remaining capacity value falls within a low-side remaining capacity area smaller than the first threshold value.

20. The power supply system according to claim 19, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is smaller than a predetermined A-th threshold value,

supply a supplied power corresponding to the demand power only from the second energy storage among the first energy storage and the second energy storage to the electric load.

21. The power supply system according to claim 20, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is larger than the A-th threshold value,

supply the supplied power corresponding to the demand power from both the first energy storage and the second energy storage to the electric load.

22. The power supply system according to claim 21, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the high-remaining-capacity area and when the demand power is larger than the A-th threshold value,

output a supplied power corresponding to the A-th threshold value from the second energy storage, and

output from the first energy storage a supplied power equal to a difference obtained by subtracting the supplied power output from the second energy storage from the supplied power corresponding to the demand power.

23. The power supply system according to claim 19, wherein the circuitry is configured to control the power transmission circuit to

output at least a base supplied power from the first energy storage when the remaining capacity value falls within the low-side remaining capacity area, and

when the remaining capacity value falls within the low-side remaining capacity area and when a supplied power corresponding to the demand power is smaller than the base supplied power,

supply a supplied power corresponding to the demand power within the base supplied power from the first energy storage to the electric load, and

charge the second energy storage with a surplus supplied power that is a difference obtained by subtracting the supplied power corresponding to the demand power from the base supplied power.

24. The power supply system according to claim 23, wherein the base supplied power comprises a supplied power set so that a sensitivity of a change in the base supplied power to a change in the demand power is lower than a sensitivity of a change in the surplus supplied power to a change in the demand power.

25. The power supply system according to claim 23, wherein the base supplied power comprises a supplied power set regardless of a value of the demand power.

26. The power supply system according to claim 23, wherein the circuitry is configured to have a function of setting the base supplied power to be variable in accordance with the remaining capacity value.

27. The power supply system according to claim 26, wherein the circuitry is configured to set the base supplied power so that the base supplied power continuously changes in response to a change in the remaining capacity value.

28. The power supply system according to claim 26, wherein the circuitry is configured to set the base supplied power so that the base supplied power increases within the low-side remaining capacity area as the remaining capacity value decreases.

29. The power supply system according to claim 23, wherein the circuitry is configured to control the power transmission circuit to,

when the remaining capacity value falls within the low-side remaining capacity area and when the supplied power corresponding to the demand power is larger than the base supplied power,

supply the supplied power corresponding to the demand power only from the first energy storage or from both the first energy storage and the second energy storage to the electric load while outputting from the first energy storage a supplied power by which the supplied power corresponding to the demand power is larger than the base supplied power.

30. The power supply system according to claim 1, wherein the electric load comprises an electric motor.

31. The power supply system according to claim 30, wherein the power transmission circuit includes

a voltage converter that converts an output voltage of at least one of the first energy storage and the second energy storage to produce a voltage and outputs the produced voltage, and

an inverter that converts a direct-current power input from the first energy storage, the second energy storage, or the voltage converter into an alternating-current power and supplies the alternating-current power to the electric motor.

32. A transportation device comprising

the power supply system according to claim 1.

33. A power transmission method for power transmission among an electric load, a first energy storage device, and a second energy storage device, the power transmission method comprising:

acquiring a demand power to be supplied to the electric load;

acquiring a remaining capacity value indicating remaining capacity in the second energy storage; and

changing a ratio of first output power output from the first energy storage to second output power output from the second energy storage to supply the demand power in accordance with the demand power and the remaining capacity value.