Electrically isolated heat dissipating junction box

• US 9,006,569 B2
• Filed: 05/24/2013
• Issued: 04/14/2015
• 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:
  US13/901,706
• Publication Number:
  US 20130312995A1
• Time in Patent Office: 690 Days
• Field of Search: 174/50, 439/535, 439/709, 439/142, 439/718, 248/906, 220/4.02
• US Class Current: 174/50
• 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. 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. The first chamber is adapted to receive a circuit board for electrical power conversion, and the metal heat sink is adapted to dissipate heat generated by the circuit board.

Claims

1. A junction box comprising:

a first chamber comprising a circuit board designed to convert electrical power from one or more power outputs of a photovoltaic panel;

a second chamber comprising an electrical connection designed to receive the electrical power from the one or more power outputs of the photovoltaic panel;

a wall common to and separating the first chamber and the second chamber;

a first lid designed to seal the first chamber against ingress of water or humidity with a first level of hermeticity; and

a second lid designed to seal the second chamber against ingress of water or humidity with a second level of hermeticity different from the first level of hermeticity.

2. The junction box of claim 1, wherein the first lid and the second lid are designed to be on opposite sides of the junction box, and wherein one of the opposite sides is attached to the photovoltaic panel.

3. The junction box of claim 1, wherein the wall comprises a second electrical connection between the first chamber and the second chamber, wherein the second electrical connection is designed to receive, from the electrical connection, the power from the one or more power outputs of the photovoltaic panel.

4. The junction box of claim 1, wherein the first lid is attached to the first chamber with a first sealing process, and wherein the second lid is attached to the second chamber with a second sealing process different from the first sealing process.

5. The junction box according to claim 1, further comprising one or more supports that mount the circuit board in the first chamber.

6. The junction box of claim 1, wherein the second chamber is includes one or more diodes.

7. The junction box according to claim 1, further comprising a re-connectable second electrical connection that connects the circuit board in the first chamber to the electrical connection in the second chamber.

8. The junction box of claim 1, further comprising a metal heat sink bonded inside the first chamber during manufacture of the junction box, wherein the metal heat sink is designed to dissipate heat generated by the circuit board.

9. The junction box of claim 8, wherein the metal heat sink is cast in situ in the first chamber during an injection molding process of manufacture of the junction box.

10. The junction box of claim 8, wherein the metal heat sink includes a dovetail structure designed to prevent mutual separation of the metal heat sink from the junction box.

11. The junction box of claim 10, wherein the dovetail structure is hollow and is designed to deform according to different rates of thermal expansion between the heat sink and the junction box.

12. The junction box of claim 8, further comprising a thermal pad designed to conduct heat and provide electrical insulation between the circuit board and the metal heat sink.

13. A junction box comprising:

a metal heat sink bonded in situ inside a first chamber, wherein the first chamber is designed to receive a circuit board designed to convert electrical power from one or more power outputs of a photovoltaic panel;

a second chamber comprising an electrical connection designed to receive the electrical power from the one or more power outputs of the photovoltaic panel;

a first lid that seals the first chamber against ingress of water or humidity with a first level of hermeticity; and

a second lid that seals the second chamber against ingress of water or humidity with a second level of hermeticity different from the first level of hermeticity.

14. The junction box of claim 13, further comprising:

a wall common to and separating the first chamber and the second chamber.

15. The junction box of claim 13, wherein the metal heat sink dissipates heat generated by the circuit board and includes a dovetail structure that prevents mutual separation of the metal heat sink from the junction box.

16. The junction box of claim 15, wherein the dovetail structure is hollow and is designed to deform during curing of a bond between the heat sink and the junction box.

17. The junction box of claim 13, further comprising a wall comprising the electrical connection, wherein the electrical connection is between the first chamber and the second chamber.

18. A method comprising:

manufacturing, using an injection molding process, a junction box comprising a first chamber, a second chamber, and a wall common to and separating the first chamber and the second chamber, wherein the junction box is designed to mount a circuit board in the first chamber, designed to receive a first lid that seals the first chamber against ingress of water or humidity with a first level of hermeticity and designed to receive a second lid that seals the second chamber against ingress of water or humidity with a second level of hermeticity.

19. The method of claim 18, further comprising:

bonding a heat sink in situ within the first chamber of the junction box during manufacture of the junction box by the injection molding process.

20. The method of claim 19, further comprising:

bonding the heat sink inside the first chamber with a dovetail structure.