An inductive turn-on snubber with passive energy recovery for IGBTs used in single ended applications and asymmetrical half bridges is presented. Snubber inductive stored energy at switch turn-off is passively recovered into the load. In so doing, limited capacitive turn-off snubbering is inherently achieved, which reduces IGBT voltage during its tail current period. Turn-on snubber energy associated with freewheel diode reverse recovery at switch turn-on, is intrinsically recovered into the load. The times for snubber set and reset are fixed, being independent of the load current magnitude. Functionality of the snubber is supported by mathematical analysis, transient analysis simulations and practical results, based on a 450 V, 33 A, 10 kHz, IGBT switching circuit. For GTO thyristors the snubber can be modified to give capacitive turn-off snubber action from zero volts. © 1998 Taylor & Francis Ltd.
|Number of pages||13|
|Journal||International Journal of Electronics|
|Publication status||Published - 1998|