Power delivery circuit with boost for energetic starting in a pulsed charge starter/alternator system

• US 6,420,793 B1
• Filed: 09/21/2000
• Issued: 07/16/2002
• Est. Priority Date: 09/21/2000
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Gale, Allan Roy, Tamor, Michael Alan, Degner, Michael W
• Primary Examiner(s): Waks, Joseph
• Application Number:
  US09/666,582
• Time in Patent Office: 663 Days
• Field of Search: 290/31, 290/34, 290/38.R, 290/50, 310/112, 310/113, 123/179.28, 320/123, 180/65.2
• US Class Current: 290/34
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0866 comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 2011/0885 Capacitors, e.g. for additional power supply
• CPC Class Codes: F02N 2011/0896 Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: F02N 2200/063 Battery voltage
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 7/48 using discharge tubes with control electrode or semiconductor devices with control electrode
• CPC Class Codes: H02P 9/08 Control of generator circuit during starting or stopping of driving means, e.g. for initiating excitation

Abstract

A method of energizing a combined starter/alternator to start an engine in a vehicle including a primary energy storage device and a secondary energy storage device. The method includes the steps of monitoring a charge value on the secondary energy storage device, and activating a converter switching circuit to charge the secondary energy storage device with the primary energy storage device until the charge value is greater than a maximum charge value. Thereafter, an inverter switching circuit is activated to energize the starter/alternator with the power available in the primary and secondary energy storage devices. The starter/alternator is activated as a starter motor until the engine starts or the charge on the secondary energy storage device falls below a mininum charge value.

Claims

1. A method of energizing a combined starter/alternator to start an engine in a vehicle including a primary energy storage device and a secondary energy storage device, the method comprising the steps of:

monitoring a charge value on said secondary energy storage device;

activating a converter switching circuit to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value; and

, thereafter

activating an inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices; and

deactivating said inverter switching circuit upon the detection of an engine running signal.

2. A method of energizing a combined starter/alternator to start an engine in a vehicle including a primary energy storage device and a secondary energy storage device, the method comprising the steps of:

monitoring a charge value on said secondary energy storage device;

activating a converter switching circuit to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value; and

, thereafter

activating an inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices; and

deactivating said inverter switching circuit after a predetermined period of time.

3. A method of energizing a combined starter/alternator to start an engine in a vehicle including a primary energy storage device and a secondary energy storage device, the method comprising the steps of:

monitoring a charge value on said secondary energy storage device;

activating a converter switching circuit to charge said secondary energy storage device with said primary energy storage device until. said charge value is greater than a maximum charge value; and

, thereafter

activating an inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices; and

detecting a first engine start signal and, in response, activating a converter circuit to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value.

4. The method of claim 3 further comprising the step of providing a secondary energy storage device charged signal to an operator when said charge value is greater than said maximum charge value.

5. The method of claim 4 further comprising the steps of detecting a second engine start signal and, when said charge value is greater than said maximum charge value, activating said inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices.

6. In a vehicle including an engine coupled to a combined starter/alternator and including a primary energy storage device and a secondary energy storage device, a method of starting said engine comprising the steps of:

detecting a first engine start signal;

in response, monitoring a charge value on said secondary energy storage device;

activating a converter switching circuit between said primary and secondary energy storage devices to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value; and

, thereafter

energizing said starter/alternator with said primary and secondary energy storage devices; and

coupling said energized starter/alternator to said engine to crank said engine until an engine running signal is detected or said charge value is less than a minimum charge value.

7. The method of claim 6 wherein the step of energizing includes the step of activating an inverter switching circuit to electrically connect said primary and secondary energy storage devices to said starter/alternator.

8. The method of claim 7 further comprising the step of deactivating said inverter switching circuit when said engine running signal is detected or said charge value is less than said minimum charge value.

9. The method of claim 7 further comprising the step of deactivating said inverter switching circuit after a predetermined period of time.

10. The method of claim 6 further comprising the steps of:

detecting said engine running signal; and

in response, periodically operating said starter/alternator as a generator at approximately a peak efficiency value; and

activating an inverter switching circuit for a predetermined period of time to charge said secondary energy storage device with said starter/alternator operating as a generator at approximately said peak efficiency value.

11. A power delivery system for a vehicle including an engine coupled to a combined starter/alternator, the system comprising:

a primary energy storage device;

a secondary energy storage device;

a converter switching circuit for electrically connecting said primary and secondary energy storage devices;

an inverter switching circuit for electrically connecting said starter/alternator and said primary and secondary energy storage devices; and

a controller programmed to perform the following steps;

monitor a charge value on said secondary energy storage device;

activate said converter switching circuit to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value; and

, thereafter

activate said inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices; and

deactivate said inverter switching circuit upon the detection of an engine running signal.

12. A power delivery system for a vehicle including an engine coupled to a combined starter/alternator, the system comprising:

a primary energy storage device;

a secondary energy storage device;

a converter switching circuit for electrically connecting said primary and secondary energy storage devices;

an inverter switching circuit for electrically connecting said starter/alternator and said primary and secondary energy storage devices; and

a controller programmed to perform the following steps;

monitor a charge value on said secondary energy storage device;

activate said converter switching circuit to charge said secondary energy storage device with said primary energy storage device until said charge value is greater than a maximum charge value; and

, thereafter

activate said inverter switching circuit to energize said starter/alternator with said primary and secondary energy storage devices; and

deactivate said inverter switching circuit after a predetermined period of time.

13. The system of claim 12 wherein said primary energy storage device is a battery and said secondary energy storage device is a capacitor.

14. The system of claim 12 wherein said inverter switching circuit and said converter switching circuit comprise MOSFET switches.

15. The system of claim 12 wherein said inverter switching circuit and said converter switching circuit comprise IGBT switches.