On-Line Testing And Monitoring Strategy Based On IGBT Power Module Reliability Research

Insulated gate bipolar transistor(IGBT)is one of the most commonly used switching devices in power electronic systems.As the core device,its failure may lead to the interruption of system operation and even cause serious safety accidents and economic losses.With the wide application of IGBT modules,their reliability issues have also received more attention from various fields.On-line monitoring technology can accurately reflect the health status of the power devices during the operation of the converters,which is an important way to effectively solve its reliability problem.This paper takes the on-line monitoring technology for IGBT modules as the research content,based on building an accelerated aging experiment platform to obtain the aging characteristics of the IGBT module,and realizes the on-line extraction of feature quantities during the accelerated aging experiment process to consolidate the concept of "online",and proposes an on-line monitoring and reconfiguration strategy for a multi-level topology with a three-level NPC inverter as an example,to optimally implement the adaptability of the three-level NPC inverter to the on-line monitoring system.This paper first introduces the physical characteristics and failure modes of IGBT modules,and builds an accelerated aging experiment platform to carry out on-line feature extraction in the accelerated aging experiment.For the problem of glue shedding during the on-line extraction,a revised plan is proposed.And the change trend of feature quantity,which is extracted through accelerated aging experiment,lays the foundation for the selection of IGBT module aging feature parameters and the on-line monitoring research of IGBT modules in the actual application environment.For the research of on-line monitoring technology,this paper takes a three-level NPC inverter as an example,proposes the modulation reconfiguration strategy to actively build an on-line monitoring environment,combined with the mature IGBT module saturated voltage drop off-line test method to achieve on-line monitoring technology.This paper introduces the IGBT module saturated voltage drop off-line test method and the monitoring system,analyzes the feasibility of on-line monitoring for the inverter,and puts forward the necessity of the on-line monitoring modulation reconfiguration strategy for the IGBT module of three-level NPC inverter.This paper models,derives and analyzes the reconfiguration strategy,and finally draws a conclusion.This conclusion explains how the inverter implements the reconfiguration strategy to actively adapt to on-line monitoring and constructs an on-line monitoring environment and how to choose the most suitable on-line monitoring moment to make the influence of the output characteristics of the inverter the smallest to solve the adaptability problem.This study builds an on-line monitoring experiment platform,and illustrates the operability and practicability of the on-line monitoring reconfiguration strategy and on-line monitoring method proposed in this paper through simulation and experiment.