Fast-Clamped Short-Circuit Protection of IGBT’s

Identification of fault current during the operation of a power semiconductor switch and activation of suitable remedial actions are important for reliable operation of power converters. A short circuit is a basic and severe fault situation in a circuit structure, such as voltage-source converters. This paper presents a new active protection circuit for fast and precise clamping and safe shutdown of fault currents of the insulated gate bipolar transistors (IGBT’s). This circuit allows operation of the IGBT’s with a higher on-state gate voltage, which can thereby reduce the conduction loss in the device without compromising the shortcircuit protection characteristics. The operation of the circuit is studied under various conditions, considering variation of temperature, rising rate of fault current, gate voltage value, and protection circuit parameters. An evaluation of the operation of the circuit is made using IGBT’s from different manufacturers to confirm the effectiveness of the protection circuit.