GRID TIE SOLAR SYSTEM AND A METHOD

• US 20100253151A1
• Filed: 04/01/2010
• Published: 10/07/2010
• Est. Priority Date: 04/01/2009
• Status: Active Grant

• Current Assignee: NXTII LLC
• Original Assignee: Too Suns, LLC
• Inventors: Ashton, Richard L., Simons, Robert J., Feltner, David R., Gerhardinger, Peter F.
• Granted Patent: US 8,779,627 B2
• Time in Patent Office: Days
• US Class Current: 307/82
• CPC Class Codes: G05F 1/67 to the maximum power available from a generator, e.g. from solar cell
• CPC Class Codes: H01L 31/02021 for solar cells electrical connection means, e.g. junction boxes, specially adapted for structural association with photovoltaic modules H02S40/34
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/26 involving maximum power point tracking control for photovoltaic sources
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

A grid tie system includes a plurality of solar panels, a plurality of inverters, wherein each of the inverters is in electrical communication with at least one of the solar panels to convert a direct current to an alternating current, wherein each of the inverters has an active state and an inactive state and at least one of the inverters includes a tracking component to track a maximum power point of at least one of the solar panels, and a controller in communication with at least one of the inverters for selectively toggling the at least one of the inverters between the active state and the inactive state.

Claims

1. A grid tie system comprising:

a plurality of solar panels;

a plurality of inverters, wherein each of the inverters is in electrical communication with at least one of the solar panels to convert a direct current to an alternating current, wherein each of the inverters has an active state and an inactive state and at least one of the inverters includes a tracking component to track a maximum power point of at least one of the solar panels; and

a controller in communication with at least one of the inverters for selectively toggling the at least one of the inverters between the active state and the inactive state.

2. The grid tie system according to claim 1, further comprising a direct current conduction bus in electrical communication with each of the solar panels and each of the inverters to provide electrical communication between at least one of the solar panels and at least one of the inverters.

3. The grid tie system according to claim 1, further comprising a disconnect box disposed between at least one of the inverters and at least one of the solar panels to provide selective electrical communication therebetween.

4. The grid tie system according to claim 1, further comprising a clamping circuit disposed between at least one of the inverters and at least one of the panel strings to limit a voltage across the at least one of the solar panels.

5. The grid tie system according to claim 4, wherein the clamping circuit includes at least one of a double pole, double throw switch and a thyristor to toggle the circuit to a short circuit condition.

6. The grid tie system according to claim 1, further comprising an electrical transformer in communication with an electrical grid and the inverters to receive an alternating current from inverters and step-up the voltage to match a voltage of the grid.

7. The grid tie system according to claim 6, further comprising an alternating current bus in electrical communication with an output of each of the inverters and the transformer to transmit the alternating current between the inverters and the transformer.

8. The grid tie system according to claim 1, wherein at least one of the inverters executes a “

perturb and observe”

routine to track a maximum power point of at least one of the solar panels.

9. The grid tie system according to claim 1, wherein at least one of the inverters transmits a feedback signal to the controller, the feedback signal representing an operational characteristic of the at least one of the inverters, and wherein the controller toggles the at least one of the inverters between the active state and the inactive state based upon an analysis of each of the feedback signal.

10. A grid tie system comprising:

a solar array including a plurality of panel strings in parallel electrical communication with each other, wherein each of the panel strings includes a plurality of solar panels;

a direct current conduction bus in electrical communication with each of the series wired panel strings;

a plurality of inverters in electrical communication with the direct current bus ring to receive a direct current generated by the solar array and to convert the direct current to an alternating current, wherein each of the inverters has an active state and an inactive state and at least one of the inverters tracks a maximum power point of at least one of the solar panels; and

a controller in communication with each of the inverters to receive a feedback signal from each of the inverters and toggle at least one of the inverters between the active state and the inactive state based upon an analysis of each of the feedback signals, wherein the feedback signal includes information about an operational characteristic of an associated one of the inverters.

11. The grid tie system according to claim 10, further comprising a disconnect box disposed between at least one of the inverters and at least one of the panel strings to provide selective electrical communication therebetween.

12. The grid tie system according to claim 10, further comprising a clamping circuit disposed between at least one of the inverters and at least one of the panel strings to limit a voltage generated by the at least one of the panel strings.

13. The grid tie system according to claim 10, further comprising an electrical transformer in communication with an electrical grid and the inverters to receive an alternating current from inverters and step-up the voltage to match a voltage of the grid.

14. The grid tie system according to claim 13, wherein the transformer includes a separate impedance balanced primary windings for each of the inverters.

15. The grid tie system according to claim 10, wherein at least one of the inverters executes a “

perturb and observe”

routine to locate a maximum power point of at least one of the solar panels.

16. The grid tie system according to claim 10, wherein the direct current conduction bus is generally ring shaped and at least one of the inverters is disposed within the ring shape of the direct current conduction bus.

17. A method of controlling a grid tie system, the method comprising the steps of

providing a plurality of solar panels;

providing a plurality of inverters, each of the inverters in electrical communication with at least one of the solar panels to receive a direct current therefrom and to convert the direct current to an alternating current, wherein each of the inverters has an active state and an inactive state and at least one of the inverters tracks a maximum power point of at least one of the solar panels;

generating a feedback signal including information about an operational characteristic of at least one of the inverters;

analyzing the feedback signal; and

toggling at least one of the inverters between the active state and the inactive state in response to the analysis of the feedback signal.

18. The method according to claim 17, further comprising the step of providing a direct current conduction bus in electrical communication with each of the solar panels and the inverters to provide an electrical intercommunication between the solar panels and the inverters.

19. The method according to claim 17, further comprising the step of transforming the alternating current to match a voltage of an electrical grid.

20. The method according to claim 17, wherein at least one of the inverters executes a “

perturb and observe”

routine to locate a maximum power point of at least one of the solar panels.