Isolated PV Junction Box With Heat Sink and Dual Chambers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing junction boxes for photovoltaic panels face challenges in efficiently dissipating heat while maintaining electrical isolation and compliance with regulations, particularly when metallic surfaces are required to be grounded, which can be inconvenient and require additional wiring.
Innovation Solution
A junction box design featuring two chambers with a common wall, where one chamber houses a metal heat sink bonded in situ for efficient heat dissipation and includes a dovetail structure to prevent separation, and a thermally conductive pad for electrical insulation, along with injection molding for secure bonding and hermetic sealing, allowing for separate access and maintenance of components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a metal heat sink is used for heat dissipation, then heat dissipation efficiency is improved, but electrical isolation is compromised and additional grounding wiring is required
Solution Approach 1:
A non-conductive adhesive layer is introduced as an intermediary between the metal heat sink and the circuit board. This adhesive layer maintains thermal contact for efficient heat dissipation while providing electrical isolation, thereby eliminating the need for additional grounding wiring and complex electrical isolation measures.
Solution Approach 2:
The thermal conductivity parameter of the adhesive layer is optimized to ensure sufficient heat transfer from the circuit board to the metal heat sink, while its electrical conductivity is maintained at non-conductive levels. This parameter optimization allows the adhesive to simultaneously serve as both a thermal pathway and an electrical insulator.
2Temperature
If the circuit board is tightly bonded to the heat sink, then heat dissipation is improved, but maintenance and upgrade of electronics becomes difficult
Solution Approach 1:
The bonding system is designed with dynamic characteristics that allow it to be strong during normal operation for effective heat dissipation, yet reversible under maintenance conditions. The non-conductive adhesive provides sufficient bonding strength for thermal contact while allowing controlled separation when maintenance is required, enabling component replacement without permanent attachment.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design effectively dissipates heat generated by the circuit board, reduces Radio Frequency Interference (RFI) emissions, and allows for easy maintenance and upgrade of electronics without disconnecting the photovoltaic panel connections, while adhering to industry standards for temperature and insulation.
Implementation Method 1
a metal heat sink bonded in situ 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
Implementation Method 2
a thermally conductive pad for electrical insulation
Implementation Method 3
injection molding for secure bonding and hermetic sealing
Data Source
AI summary
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.