On-line detection device for measuring junction temperature of IGBT power module based on saturation voltage drop

Abstract

The present invention provides an on-line detection device for measuring the junction temperature of an IGBT power module based on saturation voltage drop. According to the device, the voltages VCE of a collector and an emitter under small current are selected as temperature sensitive parameters. The detection device comprises a temperature box experimental unit. A function relationship between saturation voltage drop VCE and junction temperature Tj under the small current is determined; the switching off of high current is controlled through a switch IGBT module under a power cyclic condition; the change of the VCE at the moment when an IGBT to be detected is switched off is monitored; and the change of the VCE is introduced into the function relationship which is obtained in advance, and the change process of the junction temperature Tj can be obtained. With the device adopted, the junction temperature of the IGBT can be detected in real time. According to the device, an overcurrent unit and an overtemperature unit are additionally adopted, and therefore, the IGBT device can be protected in real time through an automatic power-off means, and therefore, the device of the present invention can obtain the junction temperature of the IGBT more simply and quickly than devices which obtain junction temperature through opening covers or changing circuit structures.

Description

technical field [0001] The invention relates to an online detection device for measuring the junction temperature of an IGBT power module based on a saturation voltage drop, belongs to the field of temperature detection devices, and particularly relates to an online detection device for the junction temperature of an IGBT module. Background technique [0002] Insulated gate bipolar transistor (IGBT) is a composite full-control voltage-driven power semiconductor device, which combines the advantages of metal oxide semiconductor field effect transistor (MOSFET) and giant transistor (GTR), with high input impedance, Easy to drive, fast switching speed, low conduction voltage drop, high voltage and high current resistance, etc., making it an ideal power component for high-power power electronic devices, which are repeatedly accelerated in rail transit, aerospace, new energy vehicles, and wind power. It is widely used in the power conversion occasions of deceleration and start / st...

AI Technical Summary

Problems solved by technology

The physical contact method requires contact measurement and is susceptible to interference from packaging materials (such as silica gel); optical method: not suitable for fully packaged modules, only suitable for research on unsealed modules in the laboratory, and the whole set of equipment is expensive

Thermal network method: After the solder layer of the IGBT module is aged, the thermal network parameters will change, and then using the original thermal parameters to calculate the junction temperature will produce large errors

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