Photovoltaic Module

• US 20130175971A1
• Filed: 01/10/2013
• Published: 07/11/2013
• Est. Priority Date: 01/11/2012
• Status: Active Grant

• Current Assignee: Solaredge Technologies Incorporated
• Original Assignee: Solaredge Technologies Incorporated
• Inventors: Har-Shai, Liron, Zohar, Alon
• Granted Patent: US 10,931,119 B2
• Time in Patent Office: Days
• US Class Current: 320/101
• 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 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

A photovoltaic module including a photovoltaic panel and an electrical circuit connected thereto. The photovoltaic panel may include multiple bus bars connected to an input of the electrical circuit. The electrical circuit may include at least one input bypass circuit connected across the bus bars at the input of the electrical circuit. Circuitry may include a switch connected between the input and the output of the electrical circuit. The circuitry may function to disconnect the photovoltaic panel from the output of the electrical circuit. An output bypass circuit is connected to the output of the electrical circuit. The output of the electrical circuit is connectable to a second like electrical circuit of a second like photovoltaic module. The output bypass circuit may be an active bypass circuit which draws power from the output of the electrical circuit.

Claims

1. An apparatus comprising:

first, second, and third nodes, wherein the first node is configured to receive an electrical current, and wherein the second and third nodes are configured to connect to respective first and second terminals of a string of one or more serially connected photovoltaic cells;

a switch configured to inhibit and conduct the current received at the first node to the second node by opening and closing the switch, respectively; and

an output bypass circuit configured to conduct the current from the first node to the third node when the switch is open, wherein the output bypass circuit includes a charge storage device operable to store charge from power applied across the first and third nodes, and operable to provide the stored charge as operating power for the output bypass circuit.

2. The apparatus of claim 1, further comprising an input bypass circuit, wherein the input bypass circuit includes a passive bypass diode operable to provide a low impedance current path to at least one of the photovoltaic cells when the at least one photovoltaic cell substantially sinks current.

3. The apparatus of claim 1, further comprising an input bypass circuit, wherein the input bypass circuit includes an active solid state switch configured to draw operating power from the string of the one or more serially connected photovoltaic cells.

5. The apparatus of claim 1, wherein the output bypass circuit further includes an active solid state switch operated using the operating power from the charge storage device.

6. The apparatus of claim 5, wherein the output bypass circuit further includes a transistor, wherein the transistor includes a source and a drain coupled respectively to the first and third nodes, and wherein the transistor further includes a gate controlled using the operating power from the charge storage device.

8. The apparatus of claim 1, wherein when the current is received at the first node, the charge storage device is charged and discharged independent of when the output bypass circuit passes the current from the first node to the third node.

9. The apparatus of claim 1, wherein the charge storage device is charged during a first period of time and discharged during a second period of time greater than the first period of time.

10. The apparatus of claim 9, wherein the first period of time is between 5 milliseconds and 15 milliseconds, and the second period of time is between 5 seconds and 15 seconds.

4. (canceled)

7. (canceled)

11. (canceled)

12. A system comprising:

a photovoltaic panel including a plurality of bus bars; and

an electrical circuit having an input and an output, wherein the plurality of bus bars are connected to the input of the electrical circuit, and wherein the electrical circuit includes;

a switch configured to inhibit and conduct current between the input and the output when the switch is open and closed, respectively; and

an output bypass circuit connected across the output of the electrical circuit and configured to conduct the current across the output when the switch is open, wherein the output bypass circuit includes;

a controller; and

a charge storage device configured to store charge from power applied across the output, and configured to provide the stored charge as operating power to the controller.

15. The system of claim 12, wherein the output bypass circuit includes a positive terminal and a negative terminal connected respectively to a positive terminal and a negative terminal of the output of the electrical circuit, wherein the output bypass circuit comprising:

a first field effect transistor (FET) with a first gate, a first drain and a first source, wherein said first drain is connected to the negative terminal of the output bypass circuit; and

a second FET with a second gate, a second drain and a second source, wherein said second source is connected to said first source, and wherein said second drain is connected to the positive terminal of the output bypass circuit.

16. The system of claim 15, wherein:

said controller is connected to said first gate and said second gate;

said controller is configured to cause a switching of said first FET and said second FET;

an input of said charge storage device is connected across said second drain and said second source;

a current flowing between the positive and negative terminals of said output bypass circuit charges said charge storage device based on said switching; and

an output of said charge storage device provides a source of direct current (DC) power to said controller by a discharge of said charge storage device based on said switching.

17. The system of claim 16, wherein said charge storage device further includes:

a zener diode with a cathode connected to said second drain and an anode connected to said second source;

a capacitor with a first terminal connected to the second source; and

a diode with an anode connected to said second drain and a cathode connected to a second terminal of the capacitor.

18. The system of claim 12, further comprising:

a second photovoltaic panel including a second plurality of bus bars; and

a second electrical circuit having a second input and a second output, wherein the second plurality of bus bars are connected to the second input, and wherein the second electrical circuit includes;

a second switch configured to inhibit and conduct current between the second input and the second output when the second switch is open and closed, respectively; and

a second output bypass circuit connected across the second output and configured to conduct the current across the second output when the second switch is open, wherein the second output bypass circuit includes;

a second controller; and

a second charge storage device configured to store a second charge from power applied across the second output, and configured to provide the second stored charge as second operating power to the second controller, wherein the output of the electrical circuit and the output of the second electrical circuit are serial connected.

13-14. -14. (canceled)

19. A method comprising:

disconnecting from a serial string of photovoltaic cells, by operation of a switch, one serial substring of a plurality of serial substrings of the photovoltaic cells, each serial substring having serially connected outputs;

passing, by operation of an output bypass circuit, current from remaining serial substrings of the plurality of serial substrings across the outputs of the one serial substring when the one serial substring is disconnected from the string of photovoltaic cells;

charging a charge storage device in the output bypass circuit from the current from the remaining serial substrings; and

providing operating power to the output bypass circuit by discharging the charge storage device.

20. The method of claim 19, further comprising:

providing, with an input bypass circuit, a low impedance current path to at least one of the photovoltaic cells when the at least one photovoltaic cell substantially sinks current.

21. The method of claim 20, further comprising:

providing operating power to an active solid state switch within the input bypass circuit from the string of photovoltaic cells.

22. The method of claim 19, further comprising:

providing the operating power from the charge storage device to an active solid state switch within the output bypass circuit when the one serial substring is disconnected by the switch from the string of photovoltaic cells.

23. The method of claim 22, wherein the output bypass circuit further includes a transistor, wherein the transistor includes a source and a drain coupled across the outputs of the disconnected one serial substring, and wherein the transistor includes a gate controlled using the operating power from the charge storage device.

24. The method of claim 19, further comprising:

charging and discharging the charge storage device independent of when the one serial substring is disconnected from the string of photovoltaic cells.

25. The method of claim 19, wherein the output bypass circuit comprises a controller configured to control switching within the output bypass circuit, and wherein the method further comprises

charging the charge storage device via an input to the charge storage device based on said switching;

and

providing the operating power as direct current (DC) power to said controller from an output of the charge storage device.