Alternator controller

• US 9,935,571 B2
• Filed: 06/10/2016
• Issued: 04/03/2018
• Est. Priority Date: 11/26/2014
• Status: Active Grant

• Current Assignee: Discovery Energy LLC
• Original Assignee: Kohler Company
• Inventors: Frampton, Isaac S., Larson, Adam, Van Maaren, Richard
• Primary Examiner(s): Cuevas, Pedro J
• Application Number:
  US15/179,323
• Publication Number:
  US 20160301345A1
• Time in Patent Office: 662 Days
• Field of Search: 322 10, 322 14, 322 17, 322 21, 322 23, 322 28, 290 55
• CPC Class Codes: H02K 7/1815 structurally associated with reciprocating piston engines general aspects of generating sets, e.g. housing, F02B63/04
• CPC Class Codes: H02P 2101/45 for motor vehicles, e.g. car alternators
• CPC Class Codes: H02P 9/00 Arrangements for controlling electric generators for the purpose of obtaining a desired output
• CPC Class Codes: H02P 9/009 Circuit arrangements for detecting rotor position
• CPC Class Codes: H02P 9/04 Control effected upon non-electric prime mover and dependent upon electric output value of the generator
• CPC Class Codes: H02P 9/14 by variation of field H02P9/08, H02P9/10 take precedence
• CPC Class Codes: H02P 9/302 Brushless excitation
• 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

Abstract

In one embodiment, a generator includes a rotor configured to rotate in cooperation with a stator to generate electrical power. A sensor, which is supported by the rotor, is configured to generate a trigger signal indicative of a position of the rotor. A communication interface is configured to receive the trigger signal from the sensor of the rotor and receive data indicative of an output of the generator. A controller supported by the rotor or configured to perform a phase analysis of the trigger signal and the output of the generator and calculate a power angle for the generator based on the phase analysis.

Claims

1. A method comprising:

detecting a change in an electrical characteristic of a field winding of an alternator;

adjusting a target field setting based on the change in the electrical characteristic of the field winding; and

changing a driving characteristic of the field winding based on the target field setting.

2. The method of claim 1, wherein the target field setting is a voltage value or a current value.

3. The method of claim 1, wherein the electrical characteristic of the field winding is field winding current.

4. The method of claim 3, wherein when field winding current increases, the target field setting is increased.

5. The method of claim 1, wherein the electrical characteristic of the field winding is field winding inductance.

6. The method of claim 5, wherein when the field winding inductance decreases, the target field setting is increased.

7. The method of claim 1, wherein the driving characteristic of the field winding is a positive voltage or a negative voltage.

8. The method of claim 1, further comprising:

calculating a load on a generator based on the electrical characteristics of the field winding.

9. The method of claim 1, further comprising:

accessing a lookup table based on a manufacturer or model of the alternator; and

receiving a threshold value for the change in electrical characteristic.

10. The method of claim 1, further comprising:

generating a pulse width modulation signal based on the target field setting, wherein a duty cycle of the pulse width modulation signal is determined from the target field setting.

11. The method of claim 1, wherein a time period from the change in an electrical characteristic to the change in target field setting is less than 100 milliseconds.

12. The method of claim 1, wherein a time period from the change in an electrical characteristic to the change in target field setting is less than one cycle of an output of the alternator.

13. An apparatus comprising:

a sensor configured to detect a change in an electrical characteristic of a field winding of an alternator; and

a controller configured to adjust a target field setting based on the change in the electrical characteristic of the field winding and generate a driving value for the field winding based on the target field setting.

14. The apparatus of claim 13, wherein the target field setting is a voltage value or a current value.

15. The apparatus of claim 13, wherein the electrical characteristic of the field winding is field winding current.

16. The apparatus of claim 13, wherein when field winding current increases, the target field setting is increased.

17. The apparatus of claim 13, wherein the electrical characteristic of the field winding is field winding inductance.

18. The apparatus of claim 13, wherein when the field winding inductance decreases, the target field setting is increased.

19. The apparatus of claim 13, wherein the controller is configured to calculate a load on a generator based on the electrical characteristics of the field winding.

20. A generator comprising:

a rotor configured to rotate in cooperation with a stator to generate electrical power;

a sensor supported by the rotor and configured to detect a change in an electrical characteristic of a field winding of the rotor; and

a controller supported by the rotor and configured to adjust a target field setting based on the change in the electrical characteristic of the field winding and generate a driving value for the field winding based on the target field setting.