Gate control circuit and switching characteristics of a MOS controll thyristor (MCT)

Abstract

The author describes a simple gate-controlled circuit for a MOS-controlled thyristor (MCT) in which the frequency, duty cycle, and pulse width are all controllable. The gate pulses generated are used to study the switching characteristics of an MCT connected in a DC chopper. Several experimental waveforms and a study of the variation of switching losses with gate pulse width are presented. It is shown that there is an increase in the switching losses with pulse width. There are also considerable oscillations both in the gate voltage and in the device voltage at higher frequencies, indicating the need for modifications in the drive circuit.<>