A construction method of igbt module state assessment and remaining life prediction model

Abstract

The invention relates to a method for constructing an IGBT module state evaluation and remaining life prediction model, comprising the following steps: measuring the electrothermal parameters of the IGBT module under different aging degrees through tests; establishing the average junction thermal resistance change rate of the IGBT module test sample. The function model of the average power cycle number and the average saturation pressure drop change rate-average power cycle number function model; according to the above function model, the aging state of the IGBT module is evaluated, and the aging of the IGBT is expressed by a real number on the interval [0,1] State, obtain the state evaluation result; establish the calculation model of the remaining life of the IGBT module according to the state evaluation result. According to the accelerated aging test of power cycle, the present invention establishes a mathematical model of electrical parameters, thermal parameters and power cycle times. The model comprehensively considers the influence of electrical parameters and thermal parameters on the evaluation results, makes up for the deficiency of single parameter evaluation, and can accurately obtain a certain Aging state of IGBT modules under junction-to-case thermal resistance and saturation voltage drop conditions.

Description

technical field [0001] The invention belongs to the technical field of power electronic devices, in particular to a method for constructing an IGBT module state evaluation and remaining life prediction model. Background technique [0002] The IGBT power module is the core power device in the fields of railways, new energy and automobiles, and its safe and reliable operation is the basis for ensuring the sustainable and stable development of all walks of life. However, because the IGBT power module is relatively fragile, it is important to study its state assessment and remaining life estimation methods for the reliability of its equipment. Since the junction-to-case thermal resistance of the IGBT power module can express the fatigue degree of the solder layer, and the saturation pressure drop can express the aging degree of the IGBT bonding wire, therefore, the above parameters represent the aging state of the IGBT power module and whether the system in which it is located c...

AI Technical Summary

Problems solved by technology

The main parameter of the analytical model analysis method is the junction temperature, and the device is predicted according to the variation range and average value of the junction temperature. However, when this method extracts the junction temperature, its accuracy fluctuates greatly, and the temperature cycle of the device Higher extraction requirements

The physical model analysis method mainly uses the experimental method. This method requires high precision of the experimental equipment and is expensive. It also needs to understand the internal structure of the IGBT module and the characteristics of the material, as well as the mechanical effects caused by the different thermal expansion coefficients between various materials. , it is more difficult to implement

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