Modeling for IGBT

Abstract

A mathematical model has been developed for an insulated gate bipolar transistor (IGBT) by compartmenting it into two diodes which are connected in series with reverse configuration. One diode is an ordinary diode while other is a controlled diode. The performance of the controlled diode depends upon the magnitude of gate emitter, GE voltage and collector emitter (CE) voltage. A GE voltage Vg > Gate Emitter Threshold Voltage (VGET), modulates the conductivity of controlled diode together with hole injection from the p+ base near the collector terminal. Parameters of these diodes are estimated by applying curve fitting tool and power invariance method. The validity of the model has been checked by a simulation example. The results of simulation show appreciable closeness with actual one.