A New Protection Circuit of Emitter Switched Thyristor (EST) for Short-Circuit Withstanding Capability

Abstract

A new protection circuit of Emitter Switched Thyristor (EST), which improves the short circuit withstanding capability is proposed and verified by 2-D simulation. The proposed EST with the new protection circuit can successfully achieve a highvoltage current saturation which can secure the shortcircuit withstanding capability because the protection circuit detects the potential of the floating n+ and decreases the gate voltage of EST while the conventional EST cannot exhibit a highvoltage current saturation. Simulation results show that a highvoltage current saturation over 600V and 10µs of short-circuit withstanding time can be successfully achieved employing a new protection circuit without increasing of the forward voltage drop.