Power Conversion Device Symmetrical Diode Module Arrangement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power conversion devices with three-level circuits face challenges in maintaining equal surge voltage duty on symmetric switching elements while reducing the degree of freedom in arranging modules, leading to uneven wire lengths and increased circuit inductance.
Innovation Solution
The power conversion device is configured with separate switching and diode modules, where the output terminals of the switching modules and diode modules are aligned symmetrically, ensuring equal wire lengths and allowing individual arrangement of diode terminals, thus maintaining equal surge voltage duty and reducing module arrangement constraints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If two diodes are incorporated in one intermediate potential module to serve as clamp diodes, then the degree of freedom in arranging modules is reduced, but it becomes difficult to make wire lengths equal between upper and lower potential sides
Solution Approach 1:
The patent divides the intermediate potential module into two separate diode modules (first diode module and second diode module). Each diode module contains only one diode, allowing them to be positioned independently. This segmentation enables the output terminal of the upper potential module to be connected to the first diode module and the output terminal of the lower potential module to be connected to the second diode module with equal wire lengths, resolving the contradiction between module arrangement flexibility and wire length equality.
2Reliability
If wire lengths between switching modules and diode modules are made equal, then surge voltage duty on symmetric switching elements becomes equal, but module arrangement becomes constrained
Solution Approach 1:
By separating the two diodes into independent diode modules, the patent allows each module to be positioned optimally to achieve equal wire lengths from the switching modules, thereby equalizing surge voltage duty on symmetric switching elements while maintaining arrangement flexibility.
Solution Approach 2:
The patent employs asymmetric arrangement of the first and second diode modules relative to the upper and lower potential switching modules. This asymmetric positioning enables equal wire lengths to be achieved despite the symmetric functional requirements, allowing flexible module arrangement while ensuring equal surge voltage duty.
3Adaptability or versatility
If unequal wire lengths are used to allow flexible module arrangement, then degree of freedom in arranging modules is maintained, but circuit inductance increases and surge voltage duty becomes uneven
Solution Approach 1:
The patent segments the diode functions into separate modules, enabling equal wire lengths to be implemented. This reduces circuit inductance compared to unequal wire length configurations, while still allowing flexible module arrangement through the independent positioning of the first and second diode modules.
Data Source
AI summary
In a power conversion device, a distance between an output terminal of a first switching module and a cathode terminal of a first diode module in a first direction is arranged to be substantially equal to a distance between an output terminal of a second switching module and an anode terminal of a second diode module in the first direction.