Methods and apparatus for power factor correction and reduction of distortion in and noise in a power supply delivery network

• US 8,450,878 B2
• Filed: 01/26/2010
• Issued: 05/28/2013
• Est. Priority Date: 01/26/2009
• Status: Active Grant

• Current Assignee: Geneva Cleantech, Inc
• Original Assignee: Geneva Cleantech, Inc
• Inventors: Rada, Patrick A., Magnasco, John H.
• Primary Examiner(s): Deberadinis, Robert L.
• Application Number:
  US12/694,153
• Publication Number:
  US 20100187914A1
• Time in Patent Office: 1,218 Days
• Field of Search: 307/105
• US Class Current: 307/105
• CPC Class Codes: G01D 2204/24 Identification of individual loads, e.g. by analysing current/voltage waveforms
• CPC Class Codes: G01D 4/004 Remote reading of utility meters to a fixed location
• CPC Class Codes: G05F 1/70 Regulating power factor; Regulating reactive current or power
• CPC Class Codes: H02J 2310/70 Load identification
• CPC Class Codes: H02J 3/002 Flicker reduction, e.g. compensation of flicker introduced by non-linear load
• CPC Class Codes: H02J 3/01 Arrangements for reducing harmonics or ripples
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 40/40 Arrangements for reducing harmonics
• CPC Class Codes: Y04S 20/242 Home appliances
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

Methods and apparatus for power factor correction include selectively coupling bit reactive loads with a load having dynamic reactive properties to dynamically correct a power factor. Methods and apparatus for reducing distortion in a power delivery system include a means for determining distortion in a power line, forming a corrective signal according to the distortion and selectively sinking and sourcing current to the power line according to the corrective signal.

Claims

1. A system for reducing distortion in an electrical signal having distortion comprising:

a. an electric circuit for comparing at least a portion of the electrical signal having distortion in a power line to a desired reference signal, thereby forming a corrective signal; and

b. an electric circuit including a plurality of selectable loads for selectively sinking and sourcing current to the electrical signal having distortion.

2. The system of claim 1 wherein distortion comprises any among harmonic distortion, noise, elevated spectral noise, and amplitude modulation.

3. The system of claim 1 further comprising a power factor correction module for bringing a power factor of the electrical signal having noise to substantially one.

4. The system of claim 3 wherein the power factor correcting module comprises:

a. a sensor for measuring the reactive power of a first load coupled to power line; and

b. a plurality of bit reactive loads for coupling with the first load to counteract a reactive component of the first load.

5. The system of claim 1 wherein the electric circuit for selectively sinking and sourcing current applies the corrective signal to at least one controlled current source, wherein the controlled current source couples a current supply with the power line according to the corrective signal.

6. The system of claim 1 wherein the electric circuit for selectively sinking and sourcing current comprises:

a. a modulator for modulating the corrective signal and applying the modulated corrective signal to at least one switch, wherein the switch couples a current supply with the power line; and

b. a filter for filtering a modulating signal.

7. The system of claim 6 wherein the modulator comprises any among a pulse width modulator, delta-sigma modulator, pulse code modulator, pulse density modulator, or pulse position modulator.

8. The system of claim 1 wherein the electric circuit for selectively sinking and sourcing current comprises:

a. a processor for selectively sourcing current into the power line in response to a negative distortion; and

b. a processor for selectively sinking current from the power line in response to a positive distortion.

9. The system of claim 1 wherein the electric circuit for selectively sinking and sourcing current comprises:

a. a processor for selectively sourcing current into the power line in response to a positive distortion; and

b. a processor for selectively sinking current from the power line in response to a negative distortion.

10. The system of claim 1, further comprising a signal generator, wherein the reference signal is generated by the signal generator.

11. An electrical circuit for reducing distortion in a current signal having distortion in a power line, the electrical circuit comprising:

a. a first input for receiving the current signal having distortion;

b. a second input for receiving a reference signal;

c. a subtractor coupled to the first input and second input for subtracting the current signal having distortion from the reference signal thereby forming a corrective signal; and

d. a circuit for selectively sinking and sourcing current from and to the current signal having distortion according to the corrective signal, the circuit comprising a plurality of selectable loads;

thereby reducing distortion in the current signal having distortion.

12. The electrical circuit in claim 11 wherein the distortion comprises any among harmonic distortion, noise, elevated spectral noise, and amplitude modulation.

13. The electrical circuit in claim 11 further comprising a power factor correction module for bringing a power factor of the signal having distortion to substantially one.

14. The electrical circuit in claim 13 wherein the power factor correction module comprises a sensor for measuring the reactive power of a first load coupled to power line and a plurality of bit reactive loads for coupling with the first load to counteract a reactive component of the first load.

15. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a. a first controlled current source coupled to the corrective signal, wherein the first controlled current source sources current to the current signal having distortion from a positive power according to the corrective signal in response to a negative distortion; and

b. a second controlled current source coupled to the corrective signal, wherein the second controlled current source sinks current from the current signal having distortion to a negative power according to the corrective signal in response to a positive distortion.

16. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a. a first controlled current source coupled to the corrective signal, wherein the first controlled current source sources current to the current signal having distortion from a positive power according to the corrective signal in response to a positive distortion; and

b. a second controlled current source coupled to the corrective signal, wherein the second controlled current source sinks current from the current signal having distortion to a negative power according to the corrective signal in response to a negative distortion.

17. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a. a positive rectifier coupled to an output of the subtractor for determining the positive portion of the corrective signal;

b. a first controlled current source coupled to a positive DC power supply configured to selectively combine the positive portion of the corrective signal with the current signal having distortion in response to a negative distortion;

c. a negative rectifier coupled to an output of the subtractor for determining the negative portion corrective signal; and

d. a second controlled current source coupled to a negative DC power supply configured to selectively combine the negative portion of the corrective signal with the current signal having distortion in response to a positive distortion.

18. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a. a positive rectifier coupled to an output of the subtractor for determining the positive portion of the corrective signal;

b. a first controlled current source coupled to a positive DC power supply configured to selectively combine the positive portion of the corrective signal with the current signal having distortion in response to a positive distortion;

c. a negative rectifier coupled to an output of the subtractor for determining the negative portion corrective signal; and

d. a second controlled current source coupled to a negative DC power supply configured to selectively combine the negative portion of the corrective signal with the current signal having distortion in response to a negative distortion.

19. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a modulator for modulating the corrective signal, thereby forming a modulated corrective signal.

20. The electrical circuit in claim 19 wherein the circuit for selectively sinking and sourcing current comprises:

a. a first switch coupled to the modulated corrective signal, wherein the first switch sources current to the current signal having distortion from a positive power source according to the corrective signal in response to a negative distortion; and

b. a second switch coupled to the modulated corrective signal, wherein the second switch sinks current from the current signal having distortion to a negative power source according to the corrective signal in response to a positive distortion.

21. The electrical circuit in claim 19 wherein the circuit for selectively sinking and sourcing current comprises:

a. a first switch coupled to the modulated corrective signal, wherein the first switch sources current to the current signal having distortion from a positive power source according to the corrective signal in response to a positive distortion; and

b. a second switch coupled to the modulated corrective signal, wherein the second switch sinks current from the current signal having distortion to a negative power source according to the corrective signal in response to a negative distortion.

22. The electrical circuit in claim 19 wherein the modulator comprises any among a pulse width modulator, delta-sigma modulator, pulse code modulator, pulse density modulator, or pulse position modulator.

23. The electrical circuit in claim 11 wherein the circuit for selectively sinking and sourcing current comprises:

a. a positive trigger comparator coupled to an output of the subtractor for determining a positive portion of the corrective signal;

b. a negative trigger comparator coupled to the output of the subtractor for determining a negative portion of the corrective signal;

c. a modulator coupled to an output of the positive trigger comparator and an output of the negative trigger comparator for pulse width modulating any among the positive portion of the corrective signal and the negative portion of the corrective signal;

d. a first switch coupled to a positive DC power supply wherein the switch is configured to selectively combine the negative corrective signal with the current signal having distortion; and

e. a second switch coupled to a negative DC power supply wherein the switch is configured to selectively combine the positive corrective signal with the current signal having distortion.

24. The electrical circuit in claim 23 wherein the modulator comprises any among a pulse width modulator, delta-sigma modulator, pulse code modulator, pulse density modulator, or pulse position modulator.

25. The electrical circuit of claim 23 further comprising at least one filter for filtering a modulating signal.

26. The electrical circuit in claim 11 further comprising processing means, wherein the processing means comprises:

a. a first analog to digital converter for digitizing the current signal having distortion;

b. a second analog to digital converter for digitizing the reference signal; and

c. a processor for digitally subtracting the digitized reference signal from the digitized current signal having distortion, thereby forming a digitized first corrective signal.

27. The electrical circuit of claim 11, further comprising a signal generator, wherein the reference signal is generated by the signal generator.