Power Module Insulation via Trench Shielding Plate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power modules face challenges in downsizing due to difficulties in ensuring insulation distances between relay terminals, as the integration of shielding plates into slits on printed circuit boards does not effectively shield exposed terminal portions, violating stipulated insulation distances.
Innovation Solution
The implementation of partition wall plates forming trenches and a shielding plate positioned within these trenches, with the shielding plate protruding beyond the slit, ensures extended insulation distances between relay terminals, allowing for shorter spacings that meet insulation standards while preventing short-circuit failures and improving assembly efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If relay terminals are integrated with sealing resin in a conventional power module, then manufacturing is simplified, but insulation distances between relay terminals cannot be ensured
Solution Approach 1:
The relay terminal structure is segmented into multiple parts: the terminal body integrated with sealing resin, and separate insulating cover portions that wrap around the terminal. This segmentation allows the insulating cover to provide additional insulation protection while maintaining the manufacturing simplicity of the integrated structure.
Solution Approach 2:
An insulating cover portion is introduced as an intermediary element between the conductive relay terminal and the external environment. This insulating cover wraps around the terminal protruding from the sealing resin, providing the necessary insulation distance without requiring changes to the terminal integration process.
2Ease of operation
If insulation distances on printed circuit board are ensured using a shielding plate in a slit, then inter-parts distances can be shorter, but exposed relay terminals cannot be completely shielded
Solution Approach 1:
The insulating cover is designed to provide localized insulation specifically at the relay terminal protruding from the sealing resin. This local quality enhancement addresses the specific insulation problem at the terminal without requiring increases in overall inter-parts distances, maintaining the benefit of compact layout.
Solution Approach 2:
The insulation solution extends from the two-dimensional plane of the printed circuit board into the third dimension by adding insulating covers that wrap around the terminal in the vertical direction. This dimensional transition provides effective shielding of the exposed terminal portions without increasing planar distances.
3Volume of moving object
If power module is downsized, then compactness is improved, but it becomes difficult to ensure creepage distances and space distances between relay terminals
Solution Approach 1:
The insulation system is segmented into multiple functional components: the sealing resin providing base insulation, and additional insulating covers providing enhanced insulation at critical terminal areas. This segmentation allows effective insulation to be concentrated where needed, enabling compact overall dimensions while maintaining required creepage and space distances.
Solution Approach 2:
Insulating covers are introduced as intermediary elements that extend the insulation path between relay terminals. These covers create additional insulation barriers that effectively increase creepage and space distances without requiring increased physical separation between terminals, thereby enabling module downsizing while maintaining insulation reliability.
Data Source
AI summary
A power module includes: a plurality of partition wall plates that are provided in a case and form a trench; a plurality of relay terminals whose electric potentials are different, that are formed so that the plurality of partition wall plates are positioned therebetween and that are formed to be opposed with each other; a printed circuit board to which the plurality of relay terminals is connected and which is provided with a slit at a position opposing the trench; and a shielding plate that is placed so that one end portion of the shielding plate is positioned in the trench, and so that an amount by which the other end portion thereof protrudes from the slit is larger than amounts by which the relay terminals protrude from the printed circuit board. The power module ensures insulation inside the power module.