| Abstract |
Humidity robustness is one of the main concerns of IGBT modules since the modules are not hermetically sealed. IGBT modules are generally filled with silicone gel which has a filter effect. Condensation amount at various condensation test conditions is described in this paper based on silicone gel humidity absorption behavior investigation. At first, the humidification condition impact is investigated. As a result, it is confirmed that condensation amount depends on dissolved humidity in silicone gel, not on the absolute humidity of ambient air. Secondly, cooling speed impact is investigated, and it is confirmed that humidification at lower temperature is effective to obtain stable results independently from cooling speed. Thirdly, it is confirmed that humidification at higher temperature is effective to shorten test time. Next, it is confirmed that humidification at lower temperature is effective to obtain stable results independently from gel thickness of the module. Finally, the calculation result is verified with the experiment. |
