Electrical system architecture having high voltage bus

• US 7,911,079 B2
• Filed: 07/31/2007
• Issued: 03/22/2011
• Est. Priority Date: 07/31/2007
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Akasam, Sivaprasad, Hoff, Brian Douglas
• Primary Examiner(s): Fureman; Jared J
• Assistant Examiner(s): Parries; Dru M
• Application Number:
  US11/882,248
• Publication Number:
  US 20090033148A1
• Time in Patent Office: 1,330 Days
• Field of Search: 307/10.1
• US Class Current: 307/10.1
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 1/00 Supplying electric power to auxiliary equipment of vehicles circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60L 1/20 Energy regeneration from auxiliary equipment
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 2210/20 AC to AC converters
• CPC Class Codes: B60L 2220/18 Reluctance machines
• CPC Class Codes: B60L 2240/62 Vehicle position
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60Y 2200/415 Wheel loaders
• CPC Class Codes: E02F 9/2075 of the hybrid type for vehicles in general B60W20/00
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

Claims

1. An electrical system architecture for a machine, comprising:

a power source configured to generate DC power at a first voltage;

a first DC bus configured to receive DC power at the first voltage from the power source;

at least one medium voltage load configured to receive DC power at the first voltage from the first DC bus;

a first DC/DC converter configured to receive DC power at the first voltage from the first DC bus and convert DC power at the first voltage to DC power at a second voltage, wherein the second voltage is greater than the first voltage;

a second DC bus configured to receive DC power at the second voltage from the first DC/DC converter;

a high voltage power storage device configured to receive DC power at the second voltage from the second DC bus and deliver DC power at the second voltage to the second DC bus;

a propulsion motor configured to receive DC power at the second voltage from the second DC bus;

an accessory motor configured to receive DC power at the second voltage from the second DC bus; and

a second DC/DC converter configured to receive DC power at the first voltage from the first DC bus and convert DC power at the first voltage to DC power at a third voltage, wherein the third voltage is less than the first voltage, and the first DC/DC converter and the second DC/DC converter are configured to divide DC power at the first voltage from the power source.

2. The electrical system architecture of claim 1, wherein the power source is at least one of a fuel cell and an engine coupled with a generator.

3. The electrical system architecture of claim 1, wherein the accessory motor is a hydraulic motor.

4. The electrical system architecture of claim 3, wherein the accessory motor is configured to drive a hydraulic implement.

5. The electrical system architecture of claim 1, wherein the accessory motor is a plurality of accessory motors.

6. The electrical system architecture of claim 1, wherein:

the propulsion motor is an AC propulsion motor; and

the electrical system architecture further includes an inverter, wherein the inverter is configured to;

receive DC power at the second voltage from the second DC bus;

convert DC power at the second voltage to AC power; and

deliver AC power to the propulsion motor.

7. The electrical system architecture of claim 1, wherein:

the accessory motor is an AC accessory motor; and

the electrical system architecture further includes an inverter, wherein the inverter is configured to;

receive DC power at the second voltage from the second DC bus;

convert DC power at the second voltage to AC power; and

deliver AC power to the accessory motor.

8. The electrical system architecture of claim 1, wherein:

the electrical system architecture further includes;

a third DC bus configured to receive DC power at the third voltage from the second DC/DC converter; and

at least one low voltage load configured to receive DC power at the third voltage from the third DC bus.

9. The electrical system architecture of claim 8, wherein:

the electrical system architecture further includes a low voltage power storage device configured to receive DC power at the third voltage from the third DC bus and deliver DC power at the third voltage to the third DC bus; and

the second DC/DC converter is further configured to receive DC power at the third voltage from the third DC bus and configured to;

convert DC power at the third voltage to DC power at the first voltage; and

deliver DC power at the first voltage to the first DC bus.

10. The electrical system architecture of claim 1, wherein the first voltage is between about 250-400 Volts.

11. The electrical system architecture of claim 1, wherein the second voltage is about 850 Volts.

12. A method, comprising:

generating a first DC power;

powering at least one medium voltage load with the first DC power;

converting at least a portion of the first DC power to a second DC power with a first DC/DC converter, wherein a voltage of the second DC power is greater than a voltage of the first DC power;

storing at least a portion of the second DC power;

driving a propulsion motor with at least one of the converted second DC power and the stored second DC power;

driving an accessory motor with at least one of the converted second DC power and the stored second DC power; and

converting at least a portion of the first DC power to a third DC power with a second DC/DC converter, wherein a voltage of the third DC power is less than a voltage of the first DC power, and the first DC/DC converter and the second DC/DC converter are configured to divide at least a portion of the first DC power.

13. The method of claim 12, wherein driving a propulsion motor includes:

converting at least one of the converted second DC power and the stored second DC power to an AC power; and

driving the propulsion motor with the AC power.

14. The method of claim 12, wherein driving an accessory motor includes:

converting at least one of the converted second DC power and the stored second DC power to an AC power; and

driving the accessory motor with the AC power.

15. The method of claim 12, wherein driving an accessory motor includes driving a plurality of accessory motors with at least one of the converted second DC power and the stored second DC power.

16. The method of claim 12, further including:

powering at least one low voltage load with the third DC power.

17. The method of claim 16, further including:

storing at least a portion of the third DC power; and

converting at least a portion of the stored third DC power to the first DC power, wherein powering at least one low voltage load includes powering the at least one low voltage load with at least one of the converted third DC power and the stored third DC power.

18. A machine comprising:

a traction device configured to propel the machine;

a hydraulic implement;

a fuel cell configured to generate DC power at a first voltage;

a first DC bus configured to receive DC power at the first voltage from the fuel cell;

a first DC/DC converter configured to receive DC power at the first voltage from the first DC bus and configured to convert DC power at the first voltage to DC power at a second voltage, wherein the second voltage is greater than the first voltage;

a second DC bus configured to receive DC power at the second voltage from the DC/DC converter;

a high voltage power storage device configured to receive DC power at the second voltage from the second DC bus and deliver DC power at the second voltage from the second DC bus;

a propulsion motor configured to;

receive DC power at the second voltage from the second DC bus; and

drive the traction device;

a hydraulic motor configured to;

receive DC power at the second voltage from the second DC bus; and

drive the hydraulic implement;

at least one medium voltage load configured to receive DC power at the first voltage from the first DC bus;

a second DC/DC converter, wherein the second DC/DC converter is configured to;

receive DC power at the first voltage from the fuel cell and the first DC/DC converter through the first DC bus and deliver DC power at the first voltage to the first DC bus; and

convert DC power at the first voltage to DC power at 24 Volts and convert DC power at 24 Volts to DC power at the first voltage;

a third DC bus configured to receive DC power at 24 Volts from the second DC/DC converter and deliver DC power at 24 Volts to the second DC/DC converter;

at least one low voltage load configured to receive DC power at 24 volts from the third DC bus; and

a low voltage power storage device configured to receive DC power at 24 Volts from the third DC bus and deliver DC power at 24 Volts to the third DC bus.