Turbine power unit for hybrid electric vehicle applications

• US 20020157881A1
• Filed: 11/13/2001
• Published: 10/31/2002
• Est. Priority Date: 11/13/2000
• Status: Abandoned Application

• Current Assignee: Capstone Turbine Corp.
• Original Assignee: Capstone Turbine Corp.
• Inventors: Geis, Everett, Wacknov, Joel, Bakholdin, Daniel, Gilbreth, Mark
• Application Number:
  US09/991,023
• Publication Number:
  US 20020157881A1
• Time in Patent Office: Days
• US Class Current: 180/65.2
• CPC Class Codes: B60K 6/24 characterised by the combustion engines
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 2050/001 Proportional integral [PI] controller
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2710/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2710/0616 Position of fuel or air injector
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A power generation system for a hybrid electric vehicle is disclosed. The system includes a fuel source, a turbogenerator coupled to the fuel source, and a power controller. The power controller is electrically coupled to the turbogenerator, and includes first and second power converters. The first power converter converts AC power from the turbogenerator to DC power on a DC bus, and the second power converter converts the DC power on the DC bus to an operating DC power on output lines. The power controller regulates the fuel to the turbogenerator, independent of DC voltage on the DC bus. The system further includes an electric motor, a drive control unit coupled between the output lines and the electric motor, and a traction battery. The traction battery is coupled across the output lines, and provides an additional source of current, upon demand, to the electric motor.

Claims

1. A power generation system for a hybrid electric vehicle, comprising:

a fuel source to provide fuel;

a turbogenerator, coupled to the fuel source, to generate AC power;

a power controller, electrically coupled to the turbogenerator, including first and second power converters, said first power converter to convert said AC power to a DC voltage on a DC bus, and said second power converter to convert said DC voltage on said DC bus to an operating DC voltage on output lines, said power controller to regulate the fuel to the turbogenerator, independent of the DC voltage on the DC bus;

an electric motor;

a drive control unit coupled between the output lines and the electric motor, said drive control unit, under control of the power controller, to couple or isolate the electric motor to or from the output lines; and

a traction battery coupled across the output lines, said traction battery to provide an additional source of current, upon demand, to the electric motor.

2. The system of claim 1 wherein the turbogenerator comprises:

a shaft;

a generator, coupled to the shaft, to generate the AC power;

a compressor, coupled to the shaft, to provide a supply of compressed air;

a combustor coupled to receive the supply of compressed air and the fuel, said combustor to combust the fuel and to provide exhaust gas;

a turbine coupled the shaft and coupled to receive the exhaust gas, said exhaust gas to flow through the turbine to control a rotational speed of the shaft; and

a recuperator including a high pressure side coupled between the compressor and the combustor, and a low pressure side coupled to receive the exhaust gas from the turbine.

3. The system of claim 1 further comprising a DC/DC converter to convert the DC voltage on the DC bus to a regulated low DC voltage, under control of the power controller.

4. The system of claim 1 further comprising a break resistor controllably coupled to the DC bus, the break resistor to sink DC power from the DC bus under control of the power controller.

5. The system of claim 1 further comprising one or more additional motors controllably coupled to the output lines.

6. The system of claim 1 further comprising:

a second electric motor;

a second drive control unit coupled between the output lines and the second electric motor, said second drive control unit, under control of the power controller, to couple or isolate the second electric motor to or from the output lines; and

a second traction battery coupled across the output lines, said traction battery to provide a second additional source of current, upon demand, to the second electric motor.

7. The system of claim 1 wherein the turbogenerator is a motor/generator and said first and second power converters are bi-directional, said power controller, in a startup mode, to configure (i) the drive control unit to isolate the electric motor from the output lines, (ii) the second power converter to supply a startup DC voltage, generated by the traction battery, on the output lines to the DC bus, and (iii) the first power converter to convert the startup DC voltage on the DC bus to power the motor/generator.

8. The system of claim 1 wherein the traction battery comprises one of the following:

a lead-acid, nickel-cadmium, nickel-metal hydride, sodium-sulphur, sodium-nickel chloride, zinc-bromine, zinc-air, and lithium battery.

9. The system of claim 1 wherein the turbogenerator and the traction battery, in combination, to provide DC power to the electric motor.

10. The system of claim 1 wherein the electric motor is an AC electric motor, and wherein the system further comprises a DC/AC converter coupled between the drive control unit and the AC electric motor.

11. The system of claim 1 wherein the power controller, in response to a brake signal, configures the drive control unit to provide a recharging DC power, generated by the electric motor, to the traction battery.

12. The system of claim 11 wherein the power controller, in response to the brake signal, further configures the first and second power converters to supply the operating DC power on the output lines to charge the traction battery.

13. The system of claim 1 further comprising an additional turbogenerator coupled to the fuel source and to generate additional AC power, said power controller to independently regulate the fuel to said turbogenerator and said additional turbogenerator, independent of the DC voltage on the DC bus.

14. The system of claim 2 further comprising a temperature sensor coupled to the turbine to sense a temperature, said sensor coupled to the power controller, said power controller to vary the fuel to the combustor to regulate the temperature, said temperature being independent of the DC voltage on the DC bus.

16. The vehicle of claim 15 wherein the turbogenerator comprises:

a shaft;

a generator, coupled to the shaft, to generate the AC power;

a compressor, coupled to the shaft, to provide a supply of compressed air;

a combustor coupled to receive the supply of compressed air and the fuel, said combustor to combust the fuel and to provide exhaust gas;

a turbine coupled the shaft and coupled to receive the exhaust gas, said exhaust gas to flow through the turbine to control a rotational speed of the shaft; and

a recuperator including a high pressure side coupled between the compressor and the combustor, and a low pressure side coupled to receive the exhaust gas from the turbine.

17. The vehicle of claim 15 further comprising a DC/DC converter to convert the DC voltage on the DC bus to a regulated low DC voltage, under control of the power controller.

18. The vehicle of claim 15 further comprising a break resistor controllably coupled to the DC bus, the break resistor to sink current from the DC bus under control of the power controller.

19. The vehicle of claim 15 further comprising one or more additional motors controllably coupled to the output lines.

20. The vehicle of claim 15 further comprising:

a second electric motor;

a second drive control unit coupled between the output lines and the second electric motor, said second drive control unit, under control of the power controller, to couple or isolate the second electric motor to or from the output lines; and

a second traction battery coupled across the output lines, said traction battery to provide a second additional source of current, upon demand, to the second electric motor.

21. The vehicle of claim 15 further comprising an additional turbogenerator coupled to the fuel source and to generate additional AC power, said power controller to independently regulate the fuel to said turbogenerator and said additional turbogenerator, independent of the DC voltage on the DC bus.

22. The vehicle of claim 15 wherein the one or more user inputs comprise START, POWER, BRAKE, and STOP signals.

23. The vehicle of claim 22 wherein the power controller, in response to the START signal, configures (i) the drive control unit to isolate the electric motor from the output lines, (ii) the second power converter to supply a startup DC voltage, generated by the traction battery, on the output lines to the DC bus, and (iii) the first power converter to convert the startup DC voltage on the DC bus to power the motor/generator.

24. The vehicle of claim 22 wherein the power controller, in response to the POWER signal, to correspondingly adjust the fuel to the turbogenerator to adjust an operating DC power on the output lines.

25. The vehicle of claim 24 wherein, when the operating DC power reaches a maximum power value, said traction battery provides instantaneous current on the output lines to drive the electric motor.

26. The vehicle of claim 22 wherein the power controller, in response to the BRAKE signal, configures the drive control unit to provide a recharging DC power, generated by the electric motor, to the traction battery.

27. The vehicle of claim 26 wherein the power controller, in response to the BRAKE signal, simultaneously configures the first and second power converters to supply the operating DC power on the output lines to charge the traction battery.

15. A hybrid electric vehicle, comprising:

one or more input devices to provide one or more user inputs;

a fuel source;

a turbogenerator to generate AC power;

a power controller electrically coupled to the turbogenerator and coupled to receive the user inputs, said power controller including first and second power converters, said first power converter to convert said AC power to a DC voltage on a DC bus, and said second power converter to convert said DC voltage on said DC bus to an operating DC voltage on output lines, said power controller to regulate the fuel flow to the turbogenerator based on at least one user input, independent of the DC voltage on the DC bus;

an electric motor;

a drive control unit coupled between the output lines and the electric motor, said drive control unit, under control of the power controller, to couple or isolate the electric motor to or from the output lines; and

a traction battery coupled across the output lines, said traction battery to provide an additional source of current to the electric motor.