Power control system and method

• US 7,812,574 B2
• Filed: 04/21/2009
• Issued: 10/12/2010
• Est. Priority Date: 04/03/2006
• Status: Expired due to Fees

• Current Assignee: C E Niehoff & Company
• Original Assignee: C E Niehoff & Company
• Inventors: Becker, James
• Primary Examiner(s): GONZALEZ, JULIO C
• Application Number:
  US12/386,732
• Publication Number:
  US 20090230680A1
• Time in Patent Office: 539 Days
• Field of Search: 290/40.C, 290/40.B, 290/40.R, 290/22, 290/51, 322/29, 322/8
• US Class Current: 322/29
• CPC Class Codes: F02D 29/06 peculiar to engines driving electric generators
• CPC Class Codes: H02P 2101/30 for aircraft
• CPC Class Codes: H02P 29/0016 Control of angular speed of one shaft without controlling the prime mover
• CPC Class Codes: H02P 9/102 for limiting effects of transients
• CPC Class Codes: H02P 9/26 using discharge tubes or semiconductor devices H02P9/34 takes precedence
• CPC Class Codes: H02P 9/30 using semiconductor devices

Abstract

This invention discloses a power control system comprising a prime mover and a generator driven by the prime mover. A control device is coupled with the generator to ascertain a change in speed of the generator and vary an output power of the generator according to the change. The control device applies a signal to reduce the generator output power and another signal to restore the generator output power. The power control system may include a transmission, a speed converter, and/or an accessory.

Claims

1. A control device for a generator driven by a prime mover, said prime mover comprising a prime mover speed indicator capable of generating a signal indicative of the prime mover speed, said generator, coupled with one or more electrical loads, comprising a generator output power controller capable of manipulating an output power of the generator, said control device comprising:

a processor, including a programming code operable on the processor, coupled with the generator output power controller and the prime mover speed indicator;

wherein said processor is configured to measure a rate of change in speed of the prime mover, via a first line, and to vary the output power of the generator by applying a speed-control signal to the generator output power controller, via a second line, according to said rate of change regardless of electrical power required by the one or more electrical loads.

2. The control device of claim 1, wherein the generator comprises at least one of a brushless alternator and a permanent magnet alternator.

3. The control device of claim 1, wherein the generator output power controller comprises at least one of a voltage regulator, a field coil, a silicon controlled rectifier, and a metal oxide semiconductor field effect transistor.

4. The control device of claim 1, wherein the prime mover speed indicator comprises a tachometer.

5. The control device of claim 1, wherein the prime mover comprises at least one of an internal combustion engine, a turbine engine, an electrical motor, a hydraulic motor, and a pneumatic motor.

6. The control device of claim 1, wherein the control device is configured to at least one of reduce and restore the generator output power when the rate of change is above a threshold value.

7. The control device of claim 6, wherein the control device is configured to reduce the generator output power when an algebraic sign of the rate of change is negative.

8. The control device of claim 7, wherein said reduction is in proportion to the rate of change.

9. The control device of claim 8, wherein said proportionality is obtained from a look up table.

10. The control device of claim 8, wherein said proportionality is obtained from a functional relationship.

11. The control device of claim 6, wherein the control device is configured to restore the generator output power when an algebraic sign of the rate of change is positive.

12. A method for controlling a generator driven by a prime mover, said prime mover comprising a prime mover speed indicator capable of generating a signal indicative of the prime mover speed, said generator, coupled with one or more electrical loads, comprising a generator output power controller capable of manipulating an output power of the generator, said method comprising:

(a) measuring a rate of change in speed of the prime mover, via a first line; and

(b) varying the output power of the generator by applying a speed-control signal to the generator output power controller, via a second line, according to said rate of change regardless of electrical power required by the one or more electrical loads.

13. The method of claim 12, further comprising maintaining an output voltage of the generator, via a voltage regulator, substantially at a regulation voltage.

14. The method of claim 12, further comprising maintaining an output voltage of the generator, via a voltage regulator, substantially at a regulation voltage and varying the regulation voltage according to said rate of change.

15. The method of claim 14, wherein the step of varying the regulation voltage comprises at least one of reducing and restoring the regulation voltage when the rate of change is above a threshold value.

16. The method of claim 15, wherein the step of varying the regulation voltage comprises reducing the regulation voltage when the algebraic sign of the rate of change is negative.

17. The method of claim 16, wherein said reduction is in proportion to the rate of change.

18. The method of claim 17, wherein said proportionality is obtained from a look up table.

19. The method of claim 15, wherein the step of varying the regulation voltage comprises restoring the regulation voltage when the algebraic sign of the rate of change is positive.

20. The method of claim 12, further comprising communicating system information.