Thermal model based health assessment of igbt

Patent metadata

Field	Value
Publication number	US-2019250205-A1
Application number	US-201815895425-A
Country	US
Kind code	A1
Filing date	Feb 13, 2018
Priority date	Feb 13, 2018
Publication date	Aug 15, 2019
Grant date	—

Abstract

An apparatus and method for determining occurrence of a fault at an insulated-gate bipolar transistor (IGBT) module is disclosed. The IGBT module and apparatus can be part of an electric vehicle. A sensor obtains a measurement of a thermal parameter of the IGBT module. A processor receives the measured thermal parameter from the sensor, and runs a model of the IGBT module to determine a thermal parameter of the IGBT module under normal operation conditions. The processor provides an alert signal to indicate the occurrence of the fault when a difference between the estimated thermal parameter and the measured thermal parameter is greater than or equal to a selected threshold.

First claim

What is claimed is:

1 . A method of determining occurrence of a fault at an insulated-gate bipolar transistor (IGBT) module, comprising:
operating a model of the IGBT module on a processor to estimate a thermal parameter of the IGBT module under normal operation conditions; measuring a thermal parameter of the IGBT module via a sensor; and providing an alert signal to indicate the occurrence of the fault when a difference between the estimated thermal parameter and the measured thermal parameter is greater than a selected threshold.

2 . The method of claim 1 , wherein the thermal parameter is at least one of: (i) a thermal resistance between the IGBT junction and a heat sink; (ii) a thermal resistance between a diode and the IGBT junction; (iii) a thermal resistance of a heat sink; and (iv) a thermal resistance of a thermistor.

3 . The method of claim 1 , wherein the thermal parameter is one of: (i) a thermal capacitance; (ii) a thermal resistance; and (iii) a thermal time constant of an element of the IGBT module.

4 . The method of claim 1 , further comprising determining the selected threshold from the estimated thermal parameters obtained from the model of the IGBT module.

5 . The method of claim 1 , further comprising determining a remaining useful life of the IGBT module.

6 . The method of claim 5 , wherein determining the remaining useful life further comprises obtaining an effective number of power cycles related to a summation of power cycles at a plurality of average temperatures and temperature swings.

7 . The method of claim 6 , further comprising applying an estimation technique to the model of the IGBT module to estimate the average temperature and temperature swing of the power cycles.

8 . An apparatus for assessing a condition of an insulated-gate bipolar transistor (IGBT) module, comprising:
a sensor configured to obtain a measurement of a thermal parameter of the IGBT module; and a processor configured to:
receive the measured thermal parameter from the sensor,
run a model of the IGBT module to determine a thermal parameter of the IGBT module under normal operation conditions, and
provide an alert signal to indicate the occurrence of the fault when a difference between the estimated thermal parameter and the measured thermal parameter is greater than or equal to a selected threshold.

9 . The apparatus of claim 8 , wherein the thermal parameter is at least one of: (i) a thermal resistance between the IGBT junction and a heat sink; (ii) a thermal resistance between a diode and the IGBT junction; (iii) a thermal resistance of a heat sink; and (iv) a thermal resistance of a thermistor.

10 . The apparatus of claim 8 , wherein the thermal parameter is one of: (i) a thermal capacitance; (ii) a thermal resistance; and (iii) a thermal time constant of an element of the IGBT module.

11 . The apparatus of claim 8 , wherein the processor is further configured to determine the selected threshold from the estimated thermal parameters obtained by running the model of the IGBT module.

12 . The apparatus of claim 8 , wherein the processor is further configured to determine a remaining useful life of the IGBT junction.

13 . The apparatus of claim 12 , wherein the remaining useful life further comprises an effective number of power cycles related to a summation of power cycles at a plurality of average temperatures and temperature swings.

14 . The apparatus of claim 13 , wherein the processor is further configured to apply an estimation technique to the model of the IGBT module to estimate the average temperature and temperature swing of the power cycles.

15 . A vehicle, comprising:
an IGBT module; a sensor configured to obtain a measurement of a thermal parameter of the IGBT module; and a processor configured to:
receive the measured thermal parameter from the sensor,
run a model of the IGBT module to determine a thermal parameter of the IGBT module under normal operation conditions, and
provide an alert signal to indicate the occurrence of the fault when a difference between the estimated thermal parameter and the measured thermal parameter is greater than or equal to a selected threshold.

16 . The vehicle of claim 15 , wherein the thermal parameter is at least one of: (i) a thermal resistance between the IGBT junction and a heat sink; (ii) a thermal resistance between a diode and the IGBT junction; (iii) a thermal resistance of a heat sink; and (iv) a thermal resistance of a thermistor.

17 . The vehicle of claim 15 , wherein the thermal parameter is one of: (i) a thermal capacitance; (ii) a thermal resistance; and (iii) a thermal time constant of an element of the IGBT module.

18 . The vehicle of claim 15 , wherein the processor is further configured to determine the selected threshold from the estimated thermal parameters obtained by running the model of the IGBT module.

19 . The vehicle of claim 15 , wherein the processor is further configured to determine a remaining useful life of the IGBT junction from an effective number of power cycles related to a summation of power cycles at a plurality of average temperatures and temperature swings.

20 . The vehicle of claim 19 , wherein the processor is further configured to apply an estimation technique to the model of the IGBT module to estimate the average temperature and temperature swing of the power cycles.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Sarwar Azeem
• Zholbaryssov Madi
• Zanardelli Wesley G
• Son Yo Chan

Classifications

• H10W90/00 Primary

  Package configurations · CPC title

• H10W40/255

  having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates · CPC title

• H10W40/00

  Arrangements for thermal protection or thermal control (integrated devices comprising arrangements for thermal protection H10D89/60) · CPC title

• H02P29/024

  Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load · CPC title

• G01R31/2619 Primary

  for measuring thermal properties thereof · CPC title