An IGBT Dynamic Characteristic Control Method Based on Miller Capacitance

With the increase of switching frequency, the turn-on current overshoot and turn-off voltage overshoot generated by IGBT switching moment are also increasing rapidly. Under the action of stray inductance, the voltage spike on the circuit load is increasing. Aiming at the problem, an active control circuit based on Miller capacitance is proposed in this paper. The active control circuit takes
$du_{ce}/dt$
and
$di_{ce}/dt$
as the control signals, which only increases the Miller capacitance of IGBT at the moment of switching, so as to reduce the switching energy loss while effectively suppressing voltage overshoot. Compared with traditional control circuits, the circuit also has the advantages of simple circuit structure, not changing the existing IGBT driving circuit, and easy to integrate with the existing driver. The performance of the designed circuit is verified by simulation software and experimental platform. The results show that the designed circuit can greatly reduce voltage overshoot and current overshoot.