Method and apparatus for a solar power conditioner

• US 6,678,176 B2
• Filed: 10/29/2001
• Issued: 01/13/2004
• Est. Priority Date: 01/18/2000
• Status: Expired due to Fees

• Current Assignee: Enviropower Corporation
• Original Assignee: Enviropower Corporation
• Inventors: Lumsden, John L.
• Primary Examiner(s): Patel, Rajnikant B.
• Application Number:
  US10/020,060
• Publication Number:
  US 20020149955A1
• Time in Patent Office: 806 Days
• Field of Search: 363/95, 363/132, 363/97, 363/46, 363/17, 363/34, 363/32, 323/222, 323/299, 323/906, 307/73, 307/66, 307/67
• US Class Current: 363/95
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/44 with means for ensuring correct phase sequence
• CPC Class Codes: H02J 3/48 Controlling the sharing of the in-phase component
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y10S 323/906 Solar cell systems

Abstract

A method and apparatus for supplementing electrical power production during peak demand power consumption is presented. A solar power conditioner converts DC electrical power provided by solar panels (or otherwise) to AC power and uses this to supplement main AC electrical power generated by a power utility (or otherwise) when needed. Both the DC power and the main AC power are digitalized by analog to digital (A/D) converters and continuously monitored by a central processor (CPU). The CPU aims to match the generated AC power of the inverter to that of the main AC power and, after tripping a breaker, supplements the main AC power with that of the converted power provided by the solar panels. In such a supplementary role, the solar power conditioner can be inserted into a utility'"'"'s distributed power grid.

Claims

1. A power conditioner for supplementing a main reference AC power with DC power from a DC power source, the power conditioner comprising:

a pulse-width modulator to modulate the DC power to provide AC power;

an analog-to-digital converter arrangement to digitize characteristic data of the main reference AC power and of the AC power to provide digitized characteristic data;

a processor arrangement to determine an operational parameter of the main reference AC power based on the digitized characteristic data; and

an adaptive filter arrangement to adapt the AC power, together with the processor arrangement, and to match it to the main reference AC power based on the operational parameter.

2. The power conditioner of claim 1, wherein the characteristic data includes at least one of power level information, current information, voltage information and phase information.

3. The power conditioner of claim 1, wherein the characteristic data includes power level information, current information, voltage information and phase information.

4. The power conditioner of claim 1, wherein the processor arrangement determines at least one of the following of the main AC reference power:

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time; and

the main reference AC power.

5. The power conditioner of claim 1, wherein the processor arrangement determines at least one of the following AC power parameters:

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time;

the AC power; and

an AC power factor.

6. The power conditioner of claim 1, wherein the processor arrangement determines at least one of the following DC power parameters:

a DC voltage,

a DC current,

the DC power, and

a conversion efficiency of converting the DC power to the AC power.

7. The power conditioner of claim 1, wherein the processor arrangement determines an adaptive DC power output of the DC power source.

8. The power conditioner of claim 1, wherein the processor arrangement determines the following main AC reference power parameters:

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content m real-time; and

the main reference AC power.

9. The power conditioner of claim 1, wherein the processor arrangement determines the following modulated AC power parameters:

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time;

the AC power; and

an AC power factor.

10. The power conditioner of claim 1, wherein the processor arrangement determines the following DC power parameters:

a DC voltage;

a DC current;

the DC power; and

a conversion efficiency of converting the DC power to the AC power.

11. The power conditioner of claim 1, wherein the processor arrangement determines:

at least one of the following main AC reference power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time, and

the main reference AC power;

at least one of the following AC power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time,

the AC power, and

an AC power factor;

at least one of the following DC power parameters;

a DC voltage,

a DC current,

the DC power, and

a conversion efficiency of converting the DC power to the AC power.

12. The power conditioner of claim 1, wherein the processor arrangement determines:

the following main AC reference power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time, and

the main reference AC power;

the following modulated AC power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time,

the AC power, and

an AC power factor;

the following DC power parameters;

a DC voltage,

a DC current,

the DC power, and

a conversion efficiency of converting the DC power to the AC power.

13. The power conditioner of claim 1, further comprising:

a circuit breaker arrangement to isolate the power conditioner from the main reference AC power, wherein the analog-to-digital converter arrangement is optically isolated so that galvanic isolation is provided.

14. The power conditioner of claim 1, wherein the processor arrangement includes a micro-controller arrangement.

15. The power conditioner of claim 1, wherein the DC power source includes a solar cell arrangement.

16. The power conditioner of claim 1, further comprising:

power supply arrangement to supply power to at least one of a battery, a battery charger, the analog-to-digital converter arrangement and the processor arrangement.

17. The power conditioner of claim 1, further comprising:

a battery to supply power to the processor arrangement if the main reference AC power is one of isolated and fails.

18. The power conditioner of claim 1, further comprising:

an electricity meter to meter data relating to a power usage for use by the processor arrangement.

19. The power conditioner of claim 1, wherein the pulse-width modulator and the adaptive filter arrangement are a modular arrangement, so that a wattage of the power conditioner can be changed by adding or removing the modular arrangement.

20. The power conditioner of claim 1, further comprising:

at least one of a serial communications port, an infrared port, an Ethernet port, a modem, and a DSL/ADSL arrangement.

21. The power conditioner of claim 1, wherein the matching of the AC power to the main reference AC power is at least one of within a time-frame of 50 micro-seconds and a degree of at least 0.1 in phase lock.

22. The power conditioner of claim 1, wherein a conversion efficiency of matching the DC power to the main reference AC power is about 96%.

23. A method of supplementing a main reference AC power with DC power from a DC power source, the method comprising:

digitizing characteristic data of the main reference AC power;

monitoring the characteristic data of the main reference AC power;

pulse-width modulating the DC power to provide AC power;

digitizing characteristic data of the AC power;

determining operational parameter data of the main reference AC power based on the digitized characteristic data of the main reference AC power and the AC power; and

matching the AC power to the main reference AC power based on the operational parameter data.

24. The method of claim 23, further comprising:

closing a circuit breaker to provide electrical isolation; and

supplementing the main reference AC power with matched AC power.

25. The method of claim 23, wherein the characteristic data of the main reference AC power includes at least one of power level information, current information, voltage information and phase information.

26. The method of claim 23, wherein the characteristic data of the main reference AC power includes power level information, current information, voltage information and phase information.

27. The method of claim 23, wherein the AC power is matched to the main reference AC power as to one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content.

28. The method of claim 23, wherein the characteristic data and operational parameter data includes:

at least one of the following main AC reference power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time, and

the main reference AC power;

at least one of the following AC power parameters;

one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content in real-time,

the AC power, and

AC power factor;

at least one of the following DC power parameters;

a DC voltage,

a DC current,

the DC power, and

a conversion efficiency of converting the DC power to the AC power.

29. An apparatus for supplementing a main reference AC power with DC power from a DC power source, comprising:

means for digitizing characteristic data of the main reference AC power;

means for monitoring the characteristic data of the main reference AC power;

means for pulse-width modulating the DC power to provide AC power;

means for digitizing characteristic data of the AC power;

means for determining operational parameter data of the main reference AC power based on the digitized characteristic data of the main reference AC power and the AC power; and

means for matching the AC power to main reference AC power based on the operational parameter data.

30. The apparatus of claim 29, wherein the characteristic data includes at least one of current information, voltage information, phase information and harmonic current information.

31. The apparatus of claim 29, wherein the characteristic data includes current information, voltage information, phase information and harmonic current information.

32. The apparatus of claim 29, wherein the AC power is matched to the main reference AC power as to one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content.

33. A power conditioner for supplementing a main reference AC power with DC power from a DC power source, comprising:

a first digitizing arrangement to digitize characteristic data of the main reference AC power;

a monitoring arrangement to monitor the characteristic data of the main reference AC power;

a pulse-width modulating arrangement to modulate the DC power to provide AC power;

a second digitizing arrangement to digitize characteristic data of the AC power;

a processing arrangement to determine operational parameter data of the main reference AC power based on the digitized characteristic data of the main reference AC power and the AC power, and to match the AC power to main reference AC power based on the operational parameter data.

34. The power conditioner of claim 33, wherein the AC power is matched to the main reference AC power as to one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content.

35. A power conditioner for supplementing a main reference AC power with DC power from a DC power source, comprising:

a pulse-width modulating arrangement to pulse-width modulate the DC power to provide AC power;

a digitizing arrangement to digitize characteristic data of the main reference AC power and of the AC power for providing digitized characteristic data; and

a determining arrangement that uses the digitized characteristic data to determine operating parameter data of the main reference AC power, and which adaptively filters the AC power to match the main reference AC power based on the operating parameter data.

36. The power conditioner of claim 35, wherein the modulated AC power is matched to the main reference AC power as to one of a root-mean-square voltage and a root-mean-square current, a phase and a harmonic content.