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RE: Please help ! IGBT exploded ...



Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com> 

 >I connected the terminals to 220V line and neutral and switched ON
 >The IGBT exploded immediately !
 >Any advise for me ?

It sounds like you connected it to AC :-0 You're supposed to put the 220V
line through a rectifier before you feed it to the IGBT. With AC, as soon as
it goes negative, the two diodes inside the half-bridge pack will short the
line and neutral together, kablooie!

However, those diodes are pretty chunky. If there was a fuse in the 220V
line, then the fuse should have blown before the diodes did. So maybe the
cause of death was something else. Perhaps your gate drive circuit didn't
have enough deadtime*, and the IGBT died from massive shoot-through? (Old
IGBTs switch OFF slowly and need some deadtime to recover. Start with 50%
deadtime and decrease it until the no-load current draw starts to climb.)

*deadtime= time when both IGBTs in the halfbridge are OFF

Steve Conner