| Abstract |
Power transistors (BIT, MOSFET, IGBT) are used in power electronic switches both in the hard switching mode and in soft switching converter topologies as Zero-Voltage-Switch (ZVS) or Zero-Current-Switch (ZCS) to realize higher switching frequencies. The switching processes may be subdevided in these cases into active and passive processes. The passive turning-on of a power electronic switch, i.e. the taking over of a load current with impressed di/dt at a switch voltage of about zero is a typical dynamic process in the ZVS-Mode. Bipolar devices react to impressed dildt with transient on-state voltage spikes and in many applications with non-negligible turn-on losses because of the conductivity modulation. The most important factors of influence on this process is discussed in the paper. A PSpice simulation of the passive turning-on of NPT-IGBT-ZVS is presented. |
