| Abstract |
The application of fast recovery diodes with high voltage blocking capabilities is increasing rapidly, thinking of the availability of turn-off devices in higher power ranges. Both devices find their use in nearly every modern power electronic switching design. Hereby, the features of the switches have been improved and for quite some time diodes have been neglected. Now new power diodes are available and data sheets promise superb freewheeling operation. But presumptions once made for small signal devices don't correspond to the true behaviour in power electronics of today. Especially turn-off characteristics are important, but with common data sheets it is unpredictable how the used diode will work in the chosen circuit. Many parameters are to be taken into account, and a special look has to be taken at probable voltage overshoots and stray inductances. The often given value of the soft factor S can only describe a narrow range of operational behaviour, if ever. A new specifying method reduces data to be given and makes it easier to choose the best diode possible in
advance. |
