Power Supply System and Vehicle

• US 20090058329A1
• Filed: 04/16/2007
• Published: 03/05/2009
• Est. Priority Date: 04/24/2006
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ichikawa, Shinji
• Granted Patent: US 7,750,505 B2
• Time in Patent Office: Days
• US Class Current: 318/139
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/20 AC to AC 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 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• 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 10/08 : 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 20/00 : 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 2510/242 : for electrical energy
• CPC Class Codes: H02J 7/0013 : acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02M 3/1582 : Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 3/1584 : with a plurality of power processing stages connected in parallel
• CPC Class Codes: H02P 2201/09 : Boost converter, i.e. DC-DC step up converter increasing the voltage between the supply and the inverter driving the motor general aspects of plural converters in cascade H02M
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• 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: 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 maximum value selection unit (50) receives battery voltage values (Vb1, Vb2) and outputs the maximum value thereof to a lower limit value limiting unit (54). A maximum value selection unit (52) receives required voltage values (Vm1*, Vm2*) and outputs the maximum value thereof to the lower limit value limiting unit (54). The lower limit value limiting unit (54) outputs a voltage reference value (Vh*) by limiting the value so as not to fall below an output value of the maximum value selection unit (50). Switching commands (PWC1, PWC2) are generated based on a control computation using a combination of a voltage feedback control element and a voltage feedforward element, and a control computation using a combination of a current feedback control element and a voltage feedforward element, respectively.

Claims

1. A power supply system having a plurality of power storage units each configured to be chargeable/dischargeable, 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 voltage conversion operation between corresponding said power storage unit and said power line;

power storage voltage value obtaining means obtaining a power storage voltage value for each of said plurality of power storage units; and

voltage reference value determination means determining a voltage reference value of electric power to be supplied to said load device in accordance with an operation status of said load device,

each of said plurality of voltage conversion units performing said voltage conversion operation in accordance with said voltage reference value determined by said voltage reference value determination means,

said voltage reference value determination means limiting said voltage reference value not to fall below the maximum power storage voltage value of said power storage voltage values obtained by said power storage voltage value obtaining means.

2. The power supply system according to claim 1, further comprising required voltage value obtaining means obtaining at least one required voltage value for said load device, and

wherein said voltage reference value determination means further determines said voltage reference value to be not less than the maximum required voltage value of said at least one required voltage value obtained by said required voltage value obtaining means.

3. The power supply system according to claim 1, further comprising voltage value detection means detecting a voltage value of said power line,

wherein at least one of said plurality of voltage conversion units performs said voltage conversion operation in response to a result of a computation including a voltage feedback control element for matching the voltage value of said power line detected by said voltage value detection means with said voltage reference value.

4. The power supply system according to claim 1, wherein at least one of said plurality of voltage conversion units performs said voltage conversion operation in response to a result of a computation including a voltage feedforward control element reflecting a value corresponding to a ratio between the power storage voltage value of corresponding said power storage unit and said voltage reference value.

5. The power supply system according to claim 4, further comprising battery current value detection means detecting a battery current value input/output to/from at least one of said plurality of power storage units,

wherein said at least one voltage conversion unit performing said voltage conversion operation in response to the result of the computation including said voltage feedforward control element performs said voltage conversion operation in response to a result of a computation including a current feedback control element for matching the battery current value of corresponding said power storage unit detected by said battery current value detection means with each current reference value.

6. The power supply system according to claim 1, wherein each of said plurality of voltage conversion units includes a chopper circuit.

7. A power supply system having a plurality of power storage units each configured to be chargeable/dischargeable, 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 voltage conversion operation between corresponding said power storage unit and said power line;

a power storage voltage value detection unit detecting a power storage voltage value for each of said plurality of power storage units; and

a control unit,

said control unit determining a voltage reference value of electric power to be supplied to said load device in accordance with an operation status of said load device,

each of said plurality of voltage conversion units performing said voltage conversion operation in accordance with said voltage reference value determined by said control unit.

said control unit limiting said voltage reference value not to fall below the maximum power storage voltage value of said power storage voltage values detected by said power storage voltage value detection unit.

8. A vehicle, comprising:

a power supply system having a plurality of power storage units each configured to be chargeable/dischargeable; and

a drive force generation unit receiving electric power supplied from said power supply system to generate drive force,

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, respectively, and each performing voltage conversion operation between corresponding said power storage unit and said power line;

power storage voltage value obtaining means obtaining a power storage voltage value for each of said plurality of power storage units; and

voltage reference value determination means determining a voltage reference value of electric power to be supplied to said drive force generation unit in accordance with an operation status of said drive force generation unit,

each of said plurality of voltage conversion units performing said voltage conversion operation in accordance with said voltage reference value determined by said voltage reference value determination means,

said voltage reference value determination means limiting said voltage reference value not to fall below the maximum power storage voltage value of said power storage voltage values obtained by said power storage voltage value obtaining means.

9. The vehicle according to claim 8, wherein said drive force generation unit includes

at least one power conversion unit configured to be capable of converting the electric power supplied from said power supply system, and

at least one electric rotating machine connected to corresponding said power conversion unit and configured to be capable of generating said drive force.

10. The vehicle according to claim 8, wherein

said power supply system further includes required voltage value obtaining means obtaining at least one required voltage value for said drive force generation unit, and

said voltage reference value determination means further determines said voltage reference value to be not less than the maximum required voltage value of said at least one required voltage value obtained by said required voltage value obtaining means.

11. The vehicle according to claim 8, wherein

said power supply system further includes voltage value detection means detecting a voltage value of said power line, and

at least one of said plurality of voltage conversion units performs said voltage conversion operation in response to a result of a computation including a voltage feedback control element for matching the voltage value of said power line detected by said voltage value detection means with said voltage reference value.

12. The vehicle according to claim 8, wherein at least one of said plurality of voltage conversion units performs said voltage conversion operation in response to a result of a computation including a voltage feedforward control element reflecting a value corresponding to a ratio between the power storage voltage value of corresponding said power storage unit and said voltage reference value.

13. The vehicle according to claim 12, wherein

said power supply system further includes battery current value detection means detecting a battery current value input/output to/from at least one of said plurality of power storage units, and

said at least one voltage conversion unit performing said voltage conversion operation in response to the result of the computation including said voltage feedforward control element performs said voltage conversion operation in response to a result of a computation including a current feedback control element for matching the battery current value of corresponding said power storage unit detected by said battery current value detection means with each current reference value.

14. The vehicle according to claim 8, wherein each of said plurality of voltage conversion units includes a chopper circuit.

15. A vehicle, comprising:

a power supply system having a plurality of power storage units each configured to be chargeable/dischargeable; and

a drive force generation unit receiving electric power supplied from said power supply system to generate drive force,

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, respectively, and each performing voltage conversion operation between corresponding said power storage unit and said power line;

power storage voltage value detection unit detecting a power storage voltage value for each of said plurality of power storage units; and

a control unit,

said control unit determining a voltage reference value of electric power to be supplied to said drive force generation unit in accordance with an operation status of said drive force generation unit,

each of said plurality of voltage conversion units performing said voltage conversion operation in accordance with said voltage reference value determined by said control unit, and

said control unit limiting said voltage reference value not to fall below the maximum power storage voltage value of said power storage voltage values detected by said power storage voltage value detection unit.