20-10-2014, 12:49 PM
Abstracts: Until the MOSFET came along in the 1970s, the bipolar transistor was the only "real" power transistor but It requires a high base current to turn on, it has relatively slow turn-off characteristics (known as current tail), and it's susceptible to thermal runaway due to its negative temperature coefficient. Also, the lowest attainable on-state voltage or conduction loss is governed by the collector-emitter saturation voltage (VCE (SAT)).[1]. so for more reliable operations other power devices are developed like GTO,IGBT,MOSFET etc.In these all devices, IGBT have advantagaes of power transistors & power MOSFETs[2]. Now IGBTs are operated by providing appropriate gate pulses in order to turn it on or off & also to protect the IGBTs from fault conditions, so we tried to make gate driver card to drive 4 IGBTs having voltage ratings of 600 volts & also tried to provide protections for different abnormal conditions.