Power Supply Insulation Connecting Plate Creepage Distance
Solution Overview
Problem
Existing power supply designs face challenges in maintaining adequate creepage distance for high-voltage components while minimizing the overall volume and maximizing circuit board utilization, as the insulation film must correspond to fastening holes, leading to either insufficient creepage distance or increased volume.
Innovation Solution
A power supply design incorporating an insulation connecting plate that is isolated between the circuit board and the metal case, featuring blind holes and protruding columns for secure fastening, allowing for increased creepage distance without increasing volume or reducing circuit board utilization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the insulation film is configured to correspond to the opening hole of the fastening area, then the fastening structure is simplified, but the creepage distance between the conversion module and the grounding outer casing is shortened
Solution Approach 1:
The insulation film is divided into two functional regions: a first insulation region that corresponds to the opening hole area for fastening, and a second insulation region that covers the high-voltage circuit board area without opening holes. This segmentation allows the fastening structure to remain simple while maintaining adequate creepage distance in the high-voltage area, as the second insulation region provides continuous insulation coverage without being interrupted by fastening holes.
2Reliability
If the actual distance between the conversion module and the grounding outer casing is increased, then the creepage distance is improved, but the overall volume of the power supply increases
Solution Approach 1:
Instead of increasing the creepage distance by expanding the physical separation in the vertical dimension (which would increase volume), the solution transitions to a two-dimensional planar insulation strategy. The second insulation region extends laterally across the high-voltage circuit board area, providing adequate creepage distance through horizontal insulation coverage rather than vertical separation, thus maintaining compact power supply volume while satisfying creepage requirements.
3Reliability
If a range is reserved on the conversion module with the fastening point as a center, then the creepage distance is improved, but the utilization rate of the circuit board deteriorates
Solution Approach 1:
The insulation film is designed with localized differentiating features: the first insulation region has opening holes positioned precisely at fastening points to enable mechanical attachment, while the second insulation region maintains continuous coverage over the high-voltage circuit board area. This local differentiation ensures that opening holes are only present where structurally necessary for fastening, not as reserved ranges that would waste circuit board space, thereby maintaining high circuit board utilization while providing adequate creepage distance through the continuous second insulation region.
Data Source
AI summary
A power supply includes a metal case, a power conversion module and an insulation connecting plate. The power conversion module is arranged in the metal case and at interval with the metal case. The power conversion module includes a circuit board. The insulation connecting plate is respectively connected with the circuit board and the metal case. The insulation connecting plate is isolated between at least a portion of the circuit board and at least a portion of the metal case. A creepage distance between the metal case and a high voltage area of the circuit board are extended by the insulation connecting plate so as to fulfill the safety requirements.