Apparatuses and Methods to Reduce Safety Risks Associated with Photovoltaic Systems

• US 20090133736A1
• Filed: 02/05/2009
• Published: 05/28/2009
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Tigo Energy, Inc
• Original Assignee: Tigo Energy, Inc
• Inventors: POWELL, Earl G., KIKINIS, Dan, HADAR, Ron, ARDITI, Shmuel
• Granted Patent: US 7,807,919 B2
• Time in Patent Office: Days
• US Class Current: 136/244
• 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: H02S 40/34 comprising specially adapted electrical connection means to be structurally associated with the PV module, e.g. junction boxes
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

Apparatuses and methods to reduce safety risks associated with photovoltaic systems by providing a safety switch on a photovoltaic panel. In one embodiment, a photovoltaic panel includes: at least one photovoltaic cell; a connector to output energy from the photovoltaic panel; and a switch coupled between the at least one photovoltaic cell and the connector. The switch is configured to disconnect the at least one photovoltaic cell from the connector during installation of the photovoltaic panel, and to connect the at least one photovoltaic cell with the connector after installation of the photovoltaic panel.

Claims

1. A photovoltaic panel, comprising:

at least one photovoltaic cell;

a connector to output energy from the photovoltaic panel; and

a switch coupled between the at least one photovoltaic cell and the connector, the switch configured to disconnect the at least one photovoltaic cell from the connector during installation of the photovoltaic panel, the switch configured to connect the at least one photovoltaic cell with the connector after installation of the photovoltaic panel;

wherein the switch comprises a removable portion which when removed connects the at least one photovoltaic cell with the connector.

2. The photovoltaic panel of claim 1, further comprising:

a junction box to host the connector, wherein the switch is integrated in the junction box.

3. The photovoltaic panel of claim 2, wherein the switch is accessible from outside of the junction box.

4. The photovoltaic panel of claim 3, wherein the switch further comprises a first conductive contactor and a second conductive contactor;

the removable portion comprises a dielectric separator;

when the dielectric separator is inserted between the first and second contactor, the switch is not connected; and

when the dielectric separate is removed, the switch is connected.

5. The photovoltaic panel of claim 4, wherein the first and second conductive contactors are spring loaded toward each other.

6. The photovoltaic panel of claim 4, wherein the removable portion further comprises a flag attached to the dielectric separator.

7. The photovoltaic panel of claim 6, wherein the flag has a visual indication of warning for electric shock.

8. The photovoltaic panel of claim 3, wherein the switch comprises a reed switch;

and the removable portion comprises a magnet.

9. The photovoltaic panel of claim 8, wherein the reed switch is a normally closed reed switch.

10. The photovoltaic panel of claim 3, wherein the switch comprises an optical sensor to turn on or off the switch based on light detected by the optical sensor;

and wherein the removable portion comprises a pull-tab configured to shield the optical sensor.

11. The photovoltaic panel of claim 10, wherein the switch comprises a semiconductor switch device or a relay.

12. The photovoltaic panel of claim 10, wherein the semiconductor switch device comprises a Field-Effect Transistor (FET).

13. The photovoltaic panel of claim 10, wherein the at least one photovoltaic cell powers the optical sensor.

14. The photovoltaic panel of claim 1, wherein the switch comprises a relay and a wiring connector to control the relay.

15. The photovoltaic panel of claim 1, further comprising:

a circuit to detect a load from an inverter, wherein the switch is to connect an output of the photovoltaic panel to the connector when the circuit detects a load from an inverter and to disconnect the output in absence of a load from an inverter.

16. The photovoltaic panel of claim 1, further comprising:

a voltage module to adjust an output of the at least one photovoltaic cell;

wherein the switch is coupled to the voltage module.

17. The photovoltaic panel of claim 16, wherein the voltage module outputs an alternating current (AC) output.

18. The photovoltaic panel of claim 16, wherein the switch comprises one of a semiconductor switch, a relay, a reed switch, and a spring loaded switch.

19. The photovoltaic panel of claim 16, wherein the switch comprises an optical sensor to control a state of the switch.

20. The photovoltaic panel of claim 16, further comprising connectors for wirings to control a state of the switch.