Electronic Module Substrate Layout for Uniform Current Path Length
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electronic modules for converting DC power to AC power for three-phase motors experience differences in current path lengths, leading to variations in impedance and inductance, resulting in increased switching noise, surge voltage, and heat generation, which shortens the lifespan of switches in half bridges.
Innovation Solution
The electronic module is designed with a substrate layout that minimizes differences in current path lengths by arranging power supply and ground terminals and wiring lines in a specific configuration, using MOSFETs for switches and shunt resistors for current detection, and capacitors for voltage stabilization, to reduce impedance and inductance differences among phases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the current path length for motor current is made uniform across all phases, then switching noise and surge voltage are reduced, but the layout complexity increases
Solution Approach 1:
The patent applies asymmetry by intentionally designing different current paths for each phase that are asymmetric in routing but symmetric in total length. Each phase has a unique path configuration (different wiring lines and components) but all paths are engineered to have equal length, thereby uniformizing electrical characteristics while maintaining layout flexibility
Solution Approach 2:
The patent changes the parameter of current path length from variable (conventional design) to uniform (invented design). By carefully adjusting and equalizing the length of current paths across all phases, the patent achieves uniform impedance and inductance values, which directly reduces switching noise and surge voltage
2Ease of manufacture
If the current path length varies among phases, then the layout is simpler, but heat generation increases due to larger switching noise
Solution Approach 1:
The patent changes the parameter of current path length from variable to uniform across all phases. By equalizing the length of current paths, the patent achieves uniform impedance and inductance, which reduces switching noise and consequently reduces energy loss in the form of heat generation
3Duration of action of stationary object
If the current path length is uniform across phases, then switch lifespan is extended, but the wiring line configuration becomes more complex
Solution Approach 1:
The patent uses asymmetry in the sense that each phase has a different wiring line configuration (asymmetric routing) but all configurations result in the same path length. This allows the patent to achieve uniform electrical characteristics and extended switch lifespan while maintaining practical wiring implementation
4Adaptability or versatility
If different current paths are used for each phase, then the layout is more flexible, but impedance differences increase
Solution Approach 1:
The patent changes the critical parameter of current path length to be uniform across all phases, despite using different routing paths. This parameter control ensures that impedance and inductance remain consistent across phases, achieving both layout flexibility and electrical stability
Data Source
AI summary
An electronic module includes a power supply wiring line disposed on a substrate along a first side and connected to a power supply terminal, a ground wiring line disposed on the substrate along a second side and connected to a ground terminal, and first to third half bridges each having a high-side switch and a low-side switch connected in series between the power supply wiring line and the ground wiring line. Connection points of the high-side switches and the low-side switches are connected to first to third motor terminals and also connected in parallel to one another. The first motor terminal, the second motor terminal, and the third motor terminal are disposed between the power supply terminal and the ground terminal.