Power Semiconductor Module with Integrated Bus Bar and Cooler

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The challenge is to improve the productivity of semiconductor packages while reducing wiring inductance, which is hindered by increased output current leading to parasitic inductance, bounced voltage, surge, and noise, causing loss and malfunction in power semiconductor elements.

Innovation Solution

A power semiconductor module design that integrates IGBTs and diodes between collector and emitter conductor plates, with a bus bar connector reducing wiring inductance by arranging the plates to minimize contact sites and using a metal-made cooler with fins for efficient heat transfer and sealing, and incorporating insulating members to bond the package to the cooler, forming a loop for the recovery current to reduce inductance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If the number of semiconductor packages is increased to improve output current, then the output current capability is improved, but the wiring inductance increases and productivity deteriorates

Engineering Contradiction:
Improveoutput currentVSAvoidproductivity
Core Design Contradiction:
PowerVSProductivity

Solution Approach 1:

The patent combines multiple semiconductor packages (upper arm and lower arm circuits) into a single integrated module housing. The collector conductor plate serves as a common electrical connection for multiple IGBTs, merging what would otherwise be separate packages into one unified structure, thereby reducing overall wiring inductance while maintaining high current capability

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The module is segmented into distinct functional sections (upper arm circuit, lower arm circuit, collector conductor plate, emitter conductor plate) that can be independently designed and assembled. This segmentation allows for optimized current paths within each section while the overall modular structure improves productivity through standardized manufacturing

Inventive Principle:
Principle #1Segmentation

2Power

If the number of semiconductor packages is increased to improve output current, then the output current capability is improved, but the wiring inductance increases causing bounced voltage and surge

Engineering Contradiction:
Improveoutput currentVSAvoidwiring inductance
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

Multiple semiconductor devices are electrically merged through the common collector conductor plate and emitter conductor plate, creating parallel current paths that reduce overall wiring inductance. The integrated structure eliminates the need for external wiring between separate packages, thereby reducing bounced voltage and surge

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent transitions from a planar arrangement of separate packages to a three-dimensional integrated structure where conductor plates extend in multiple dimensions. The collector and emitter conductor plates create vertical and horizontal current paths that optimize electrical connectivity and reduce inductance across multiple spatial dimensions

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Temperature

If both-side cooling is implemented to improve cooling efficiency, then the thermal capacity is improved, but the device complexity increases

Engineering Contradiction:
Improvecooling efficiencyVSAvoiddevice complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The cooling function is merged with the structural housing of the module. The housing itself serves as a heat dissipation structure with cooling channels integrated into its design, eliminating the need for separate cooling components and reducing overall device complexity while maintaining effective both-side cooling

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The module housing serves multiple functions: mechanical protection of semiconductor devices, structural support, electrical insulation, and thermal management through integrated cooling channels. This multi-functionality reduces the number of separate components needed, thereby reducing device complexity while maintaining cooling efficiency

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

This design inhibits productivity decline and reduces wiring inductance, enhancing the efficiency and reliability of the power semiconductor module by minimizing heat generation and noise, thus improving the output of the power converter.

Implementation Method 1

both principal surfaces of a power semiconductor element are interposed between lead frames that are tabular conductors and the surfaces of the lead frames opposite to the surfaces facing the respective principal surfaces of the power semiconductor element are thermally coupled with a coolant and cooled

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

a metal-made cooler with fins for efficient heat transfer

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP2725699B1Power semiconductor module and electric power conversion device using same
Publication Date: 2020.05.13 HITACHI AUTOMOTIVE SYST LTD
  • EP2725699B1 patent drawingFigure 1
  • EP2725699B1 patent drawingFigure 2(a)~2(b)
  • EP2725699B1 patent drawingFigure 3(a)~3(c)

AI summary

A power semiconductor module includes a first package having an upper arm circuit section, a second package having a lower arm circuit section, a metal case having a storage space to store the first package and the second package and an opening connecting with the storage space, and an intermediate connecting conductor to couple the upper arm circuit section with the lower arm circuit section; the case includes a first radiating section and a second radiating section facing the first radiating section through the storage space; the first package is arranged so that the arrangement direction of the first and second packages may be parallel to the respective surfaces facing the first and second radiating sections; and the intermediate connecting conductor couples an emitter side terminal extending from the first package with a collector side terminal extending from the second package in the storage space.