Fast clamped short circuit protection of IGBTs

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