重复过流冲击下IGBT的性能退化研究

Performance Degradation Research on IGBT under Repetitive Over-Current Conditions

实际应用中,功率变流器经常会发生过流,重复的过流冲击会造成其功率器件绝缘栅型双极性晶体管(IGBT)的性能退化,并形成累积损伤,最终导致失效,而突然的失效会带来经济损失和安全问题,故需对重复过流冲击下IGBT的性能退化进行研究,建立相应的在线监测方法.针对目前对IGBT在重复过流下性能退化的研究较欠缺,搭建了过流冲击的实验平台来实现IGBT的重复过流冲击实验;采集重复过流冲击过程中IGBT外部端子的电气量,并提出相应的新的性能退化指标——导通电阻.结果表明:重复过流冲击会造成IGBT的性能退化,影响其外部电气特性;提出的退化指标——导通电阻明显地表征了IGBT内部累积损伤的程度.

In the practical application, over-current conditions often emerge during the operation of power converters. The repetition of over-current conditions is responsible for the performance degradation and cumulative damage of power devices（IGBTs）, which eventually leads to a failure. Since sudden failures will cause safety issues and economic losses, it is necessary to investigate the performance degradation of IGBT under repetitive over-current conditions and establish the corresponding on-line monitoring approaches. However, the research about performance degradation of IGBT under repetitive over-current conditions is insufficient. An experimental platform was presented, with which a series of repetitive overcurrent experiments had been completed. In the meantime, terminal electrical characteristics of IGBT were acquired to extract a new aging indicator, on resistance. The experimental results showed that the performance of IGBT degraded under repetitive over-current conditions, which affected the terminal electrical characteristics of IGBT. And the proposed aging indictor, on resistance, evidently showed the degree of accumulative damage in IGBT.