Investigation on the Short-Circuit Behavior of an Aged IGBT Module Through a 6 kA/1.1 kV Non-Destructive Testing Equipment

摘要

This paper describes the design and development of a 6 kA/1.1 kV non-destructive testing system, which aims for short circuit testing of high-power IGBT modules. An ultralow stray inductance of 37 nH is achieved in the implementation of the tester. An 100 MHz FPGA supervising unit enables 10 ns level control accuracy of the short-circuit duration, protection triggering, and acquisition of the electrical waveform. Moreover, a protection circuit avoids explosions in case of failure, making the post-failure analysis possible. A case study has been carried out on an aged 1.7 kV IGBT power module. The case study shows the current and voltage waveform during short-circuit, as well as the current mismatch among six inner sections, which demonstrate the capability and the effectiveness of the proposed setup in the short-circuit aspect reliability studies of MW-scale power modules.