Condition Monitoring of IGBT Power Modulesby Real-Time Measurement of the IGBT Junction Temperature

Dr.-Ing. Marco Denk

University of BayreuthGraduated in April 2016

Doctoral thesis

High voltagebattery

Power module E-M

achin

eFuel tank

IAEK0

Power Modules:

Central role in electric & hybrid drivetrains.

Hybrid strategies

Functionality

Efficiency

Reliability

Costs

Electric drivetrain

Motivation

Very uncertain

operating load!

Advanced IGBT Gate Driver

To bring light into the darkness…

New IGBT Gate Driver:

Real-Time Measurement of IGBT Junction Temperature.

Recording of Load-Histories.

Monitoring of Health-State (Power Module + Cooling Sysytem)

Compact solution for Condition

Monitoring!

Advanced IGBT Gate Driver

… the on-chip

internal gate resistor

of the IGBT is used as

a temperature sensor.

For Real-Time TJ-Measurement …

… a small identification signal is modulated on the gate voltage.

RGi = f(TJ)UGoff

UG / V

t / µs

UGon

Advanced IGBT Gate Driver

Modified output

stage

Automatic calibration

function

Simple integrationNew IGBT Gate Driver

New IGBT Gate

Driver

Isolated interface

Target Application

Advanced IGBT Gate Driver

During start-up … During driving …

Measured with IGBT

Gate Driver

Verification with IR cam

First working sensor system that offers deep insights into the operation of the power module.

Experimental verification

Online Rainflow-Counting

During longer road-trials …

Temperature-ProfileLoad-History

“Temperature cycles”

Online-Rainflow

AlgorithmCompress data by 99%

Online-Rainflow

Algorithm

“Temperature cycles”

Cooling-System

DCB-Ceramic

Baseplate

… give information about the health-state.

Health-Monitoring

Health-Monitoring:

Health-Indicator:

Increase of thermal resistances in different material layers.

Power Module

Cooling System

Temperature cycles during start-up …

Power module structure

Health-State

Health-State

SemiconductorChip-solder

Conclusions

New IGBT Gate Driver

Junction Temperature

Load-History

Active cycles

Passive cycles

Health-State

Power Module

Cooling System

In summary …

In future …

“Early failure detection”

Dr.-Ing. Marco Denk

University of BayreuthGraduated in April 2016

Thank you for your attention.

ISBN: 978-3-8439-2626-6

Doctoral thesis