Fault Diagnosis And Status Monitoring Of Power Semiconductor Devices

As the core device of the power conversion system,power semiconductor devices play a vital role in the safe and reliable operation of converter devices,and are of great significance to maintaining normal production,living order,safety of life and property.However,with the advancement of industrial production technology,the working requirements of the power conversion device are getting higher and higher,which leads to the worsening of the working environment of the conversion system and the obvious increase in the failure rate.Therefore,research on the condition monitoring technology of power semiconductor modules is an effective measure to improve the safety and reliability of the converter system.This paper selects the two most mainstream power semiconductor devices,Si-based IGBT and SiC MOSFET,to study the module structure,working principle,performance,heat distribution,development process of bonding wire failure,and bonding wire state monitoring methods.The specific content is as follows:Firstly,it analyzes the structure of IGBT and SiC MOSFET modules,and respectively introduce the non-Kelvin drive structure commonly used by IGBT and the Kelvin drive structure used by SiC MOSFET modules,and explore the effects of the two structures on the device through simulation software.The influence on turn on speed characteristics and current sharing characteristics is discussed.Taking the failure of the bonding wire as the research object,the main failure forms of the bonding wire and its inducements are summarized.Based on the ANSYS workbench simulation platform,a simulation model of the power module is built.Based on the built simulation model,the failure process of the bonding wire is analyzed from the perspective of heat distribution.Based on the above research results,taking the Kelvin structure as the research object,the driving current and power current at the time of turn-off are analyzed,and two decoupling models of the loop are given.Based on the bond wire failure problem,the above model is extended to any healthy state.Aiming at the problem of the parasitic parameters of the bonding wire,a simulation model of the bonding wire is built based on the ANSYS Q3 D platform,and the parasitic resistance and the parasitic inductance of the bonding wire within a certain frequency range are extracted with the frequency.A method for monitoring the health status of bonding wires suitable for Kelvin structure is proposed.Theoretical analysis and calculation formulas are given,and corresponding simulation models and waveforms are given.The correctness of the proposed method is verified on the experimental platform.The paper has 95 pictures,14 tables,and 90 references.