5SHX2645L0004 5SHX series thyristor

IGCT is a combination of GCT(gate commutated thyristor) and integrated gate drive circuit, which has GTO high blocking capability and low on-state voltage drop, as well as the same switching performance as IGBT, is an ideal megawatt-level, medium-voltage switching device, widely used in high-power medium-voltage converters. The basic working principle is as follows:

When the IGCT works in the on-state, it is a positive feedback switch like a thyristor, which is characterized by strong current carrying capacity and low on-state voltage. In the off state, the pn junction between the IGCT gate and the cathode enters the reverse bias in advance, and effectively exits the work, the entire device works in a transistor way, the equivalent circuit diagram of the device in these two states, IGCT off, by opening a switch in series with the cathode (usually MOSFET), the P base n emitter is reversed. This quickly prevents cathode injection, forcing the overall anode current into a gate current (usually within ls), thus transforming the GTO into a contactless base PNP transistor, eliminating the cathode emitter contraction effect. As a result, its maximum turn-off current is much higher than the rated current of a conventional GTO. Since the IGCT is turned off when the gain approaches 1, the protective absorption circuit can be omitted.