Adaptive dv/dt and di/dt control for isolated gate power devices

This paper describes an adaptive gate control technique and a driver concept for isolated gate power devices. The proposed technique modulates the gate current of the power devices to control dv/dt and di/dt during a switching transition. It uses different time intervals, which are adjusted successively. Delays of the driver and the control section are compensated and therefore the proposed technique is applicable to control fast switching transients. To detect the di/dt during switching, a feedback path is implemented using parasitic inductances in the power section of the converter. By application of this method, we achieved the following properties: low propagation delays, reduced voltage overshoots, improved EMI and reduced switching power losses. The proposed method is applicable to converters with half-bridge, full-bridge and three-phase bridge configuration.