ACG OUTPUT VOLTAGE CONTROL

• US 20090184693A1
• Filed: 01/22/2008
• Published: 07/23/2009
• Est. Priority Date: 01/22/2008
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Fujiwara, Tadashi, Owens, Richard
• Granted Patent: US 8,334,679 B2
• Time in Patent Office: Days
• US Class Current: 322/37
• CPC Class Codes: H02J 7/14 for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
• CPC Class Codes: H02J 7/1438 in combination with power supplies for loads other than batteries
• CPC Class Codes: H02P 2101/45 for motor vehicles, e.g. car alternators
• CPC Class Codes: H02P 9/48 Arrangements for obtaining a constant output value at varying speed of the generator, e.g. on vehicle H02P9/04 - H02P9/46 take precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A generator control system is provided in a vehicle having an engine that drives an electric power generator arranged to selectively provide electric power to an electrical load of the vehicle and to selectively charge a battery of the vehicle. The generator control system includes: a sensor that detects a state of charge (SOC) of the battery; and, a controller that controls a voltage output mode of the generator in response to the SOC detected by the sensor.

Claims

1. In a vehicle having an engine that drives an electric power generator arranged to selectively provide electric power to an electrical load of the vehicle and to selectively charge a battery of the vehicle, a generator control system comprising:

a sensor that detects a state of charge (SOC) of the battery; and

a controller that controls a voltage output mode of the generator in response to the SOC detected by the sensor.

2. The generator control system of claim 1 wherein the generator is operable in one of two modes including a Hi voltage output mode and a LO voltage output mode.

3. The generator control system of claim 2 wherein the controller provides a control signal to the generator based upon the SOC detected by the sensor, said control signal instructing the generator to operate in a selected one of the two modes when the SOC is outside a determined range, otherwise said generator being free to selectively switch between the HI and LO voltage output modes when the SOC is within the determined range.

4. The generator control system of claim 3 wherein the control signal instructs the generator to operate in the LO voltage output mode when the SOC is above a first determined threshold.

5. The generator control system of claim 4 wherein the control signal instructs the generator to operate in the Hi voltage output mode when the SOC is below a second determined threshold.

6. The generator control system of claim 5 wherein the first determined threshold is in an approximate range of between 98% to 110%.

7. The generator control system of claim 6 wherein the second determined threshold is in a range of approximately 20% to 80%.

8. The generator control system of claim 7 wherein an output voltage of the generator when operating in the Hi voltage output mode is approximately 14.5 volts.

9. The generator control system of claim 8 wherein the output voltage of the generator when operating in the LO voltage output mode is approximately 12.5 volts.

10. The generator control system of claim 9 wherein the generator is an alternator.

11. In a vehicle having an engine that drives an electric power generator arranged to selectively provide electric power to an electrical load of the vehicle and to selectively charge a battery of the vehicle, a method for controlling a voltage output mode of the generator comprising:

(a) determining a state of charge (SOC) of the battery; and

(b) controlling a voltage output mode of the generator in response to the SOC.

12. The method of claim 11 wherein the generator is operable in one of two modes including a HI voltage output mode and a LO voltage output mode.

13. The method of claim 12 wherein an output voltage of the generator when operating in the LO voltage output mode is approximately 12.5 volts.

14. The method of claim 12 wherein the output voltage of the generator when operating in the HI voltage output mode is approximately 14.5 volts.

15. The method of claim 12, wherein step (b) comprises:

compelling the generator to operate in a selected one of the two modes when the SOC is outside a determined range; and

allowing said generator to freely switch between the HI and LO voltage output modes when the SOC is within the determined range.

16. The method of claim 15 wherein the step of compelling comprises:

comparing the SOC to a threshold; and

compelling the generator to operate in the HI voltage output mode if the SOC is less than the threshold.

17. The method of claim 16 wherein the threshold is approximately 80%.

18. The method of claim 15 wherein the step of compelling comprises:

comparing the SOC to a threshold; and

compelling the generator to operate in the LO voltage output mode if the SOC is greater than the threshold.

19. The method of claim 18 wherein the threshold is in an approximate range of between 98% to 110%.

20. In a vehicle having an engine that drives an electric power generator arranged to selectively provide electric power to an electrical load of the vehicle and to selectively charge a battery of the vehicle, a system for controlling a voltage output mode of the generator comprising:

means for determining a state of charge (SOC) of the battery; and

means for controlling a voltage output mode of the generator in response to the SOC.