Electrically isolated heat dissipating junction box

• US 9,748,896 B2
• Filed: 03/09/2015
• Issued: 08/29/2017
• Est. Priority Date: 05/22/2009
• Status: Active Grant

• Current Assignee: Solaredge Technologies Incorporated
• Original Assignee: Solaredge Technologies Incorporated
• Inventors: Sella, Guy, Handelsman, Lior, Shmukler, Vadim, Adest, Meir, Gazit, Meir, Galin, Yoav
• Primary Examiner(s): Patel, Dhirubhai R
• Application Number:
  US14/641,690
• Publication Number:
  US 20150181738A1
• Time in Patent Office: 904 Days
• Field of Search: 136244
• CPC Class Codes: G08B 13/1409 for removal detection of electrical appliances by detecting their physical disconnection from an electrical system, e.g. using a switch incorporated in the plug connector
• CPC Class Codes: H02G 15/10 protected by boxes, e.g. by distribution, connection or junction boxes
• 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: H02S 40/345 with cooling means associated with the electrical connection means, e.g. cooling means associated with or applied to the junction box cooling means for PV cells H01L31/052, for PV modules H02S40/42
• CPC Class Codes: H05K 5/02 Details
• CPC Class Codes: H05K 5/062 sealed by a material injected between a non-removable cover and a body, e.g. hardening in situ
• CPC Class Codes: H05K 7/2039 characterised by the heat transfer by conduction from the heat generating element to a dissipating body arrangements for increasing/decreasing heat-transfer, e.g. fins details, F28F13/00
• CPC Class Codes: H05K 9/0007 Casings standardised racks H05K9/0062
• CPC Class Codes: H05K 9/0009 with provisions to reduce EMI leakage through the joining parts
• CPC Class Codes: H05K 9/0015 Gaskets or seals
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y10S 248/906 Electrical outlet box support
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A junction box used for making electrical connections to a photovoltaic panel. The junction box has two chambers including a first chamber and a second chamber and a wall common to and separating both chambers. The wall may be adapted to have an electrical connection therethrough. The two lids are adapted to seal respectively the two chambers. The two lids are on opposite sides of the junction box relative to the photovoltaic panel. The two lids may be attachable using different sealing processes to a different level of hermeticity. The first chamber may be adapted to receive a circuit board for electrical power conversion. The junction box may include supports for mounting a printed circuit board in the first chamber. The second chamber is configured for electrical connection to the photovoltaic panel. A metal heat sink may be bonded inside the first chamber.

Claims

1. A junction box comprising a first chamber and a second chamber separated by a wall and designed to be mounted to a photovoltaic panel, wherein:

the first chamber comprises a circuit board designed to convert electrical power received from the photovoltaic panel to at least one of a DC voltage or an AC voltage;

the second chamber comprises an electrical connection designed to receive the electrical power from the photovoltaic panel;

the wall allows for mutual separation and reattachment of the first chamber and the second chamber; and

the first chamber is configured to disconnect from the photovoltaic panel without disconnecting the second chamber from the photovoltaic panel.

2. The junction box of claim 1, further comprising a heat sink having a dovetail structure, wherein at least a portion of the dovetail structure is adapted to deform to prevent mutual separation of the heat sink and the first chamber.

3. The junction box of claim 2, wherein the dovetail structure comprises a hollow portion to allow for deforming of at least the portion of the dovetail structure.

4. The junction box of claim 1, further comprising a first lid and a second lid, wherein:

the first lid is designed to seal a first end of the first chamber;

the second lid designed to seal a second end of the second chamber; and

the second chamber comprises an open end designed to mount flat to the photovoltaic panel.

5. The junction box of claim 4, wherein the first chamber is sealed via the first lid with a first level of hermiticity, and wherein the second chamber is designed to be sealed via the second lid with a second level of hermiticity different than the first level of hermiticity when the open end is mounted flat to the photovoltaic panel.

6. The junction box of claim 1, wherein the wall is common to and separates the first chamber and the second chamber, and wherein the circuit board and the electrical connection are connected by a bus bar.

7. The junction box of claim 6, wherein the bus bar is sealed in the wall to maintain a first level of hermeticity for the second chamber.

8. The junction box of claim 1, further comprising a support adapted to mount a bus bar, wherein a first end of the bus bar is connected to the circuit board via a first connector and a second end of the bus bar is connected to the electrical connection via a second connector, wherein the support maintains a hermetic sealing between the first connector and the second connector.

9. The junction box of claim 1, further comprising a thermal pad between a heat sink and the first chamber, wherein the thermal pad is adapted to deform to accommodate non-uniformity in a surface of the heat sink and in a surface of the first chamber.

10. A junction box comprising:

a first chamber, the first chamber comprising a circuit board designed to convert electrical power received from a photovoltaic panel to at least one of a DC voltage or an AC voltage;

a second chamber comprising an electrical connection designed to receive the electrical power from the photovoltaic panel; and

a double wall constructed between the first chamber and the second chamber such that the first chamber and the second chamber are mutually separable and re-attachable.

11. The junction box of claim 10, wherein the first chamber is sealed with a first level of hermiticity by a first lid and the second chamber is sealed with a second level of hermiticity by a second lid, wherein the second level of hermiticity is different than the first level of hermiticity.

12. The junction box of claim 10, wherein the first chamber is hermetically sealed by a first lid and the second chamber comprises an open end designed to mount flat against the photovoltaic panel.

13. The junction box of claim 12, further comprising a gasket configured to seal the open end of the second chamber.

14. The junction box of claim 10, further comprising:

supports in the first chamber for mounting the circuit board; and

terminals mounted in the second chamber, the terminals connecting the electrical connection to the photovoltaic panel.

15. The junction box of claim 14, further comprising a bypass diode connected between the terminals.

16. The junction box of claim 10, further comprising a shielded lid that seals the first chamber and is adapted to suppress Radio Frequency Interference (RFI) emissions from the junction box.

17. The junction box of claim 16, wherein the sealing of the first chamber by the shielded lid electrically isolates the junction box.

18. A method of manufacturing a junction box, the method comprising:

installing, in a first chamber of the junction box, a circuit board that converts electrical power received from a photovoltaic panel to at least one of a DC voltage or an AC voltage;

installing, in a second chamber of the junction box, an electrical connection to receive the electrical power from the photovoltaic panel; and

connecting the first chamber to the second chamber at a double wall between the first chamber and the second chamber, the double wall being adapted to provide for mutual separation and re-attachment of the first chamber to the second chamber.

19. The method of claim 18, further comprising sealing the first chamber with a first level of hermeticity and the second chamber with a second level of hermeticity different than the first level of hermeticity.

20. The method of claim 18, further comprising:

connecting the circuit board and the electrical connection with a bus bar; and

sealing the bus bar to the double wall to maintain a first level of hermeticity.