High side mosfet offset volatge in phase shifted full bridge converter

Thread Starter

Vinay Kurapati

Joined Nov 19, 2018
I am working on phase shifted full bridge converter. The input voltage of it is 300 V.

The issue is I am able to see offset voltage (shown in fig below) in the gate to source pulses during turn-off period of high side MOSFET when input voltage of 300 V or even less than that applied to it.

Without input voltage applied the gate to source pulses are clear and there is no offset. This issue was happening only on high side MOSFETs but at the low side MOSFETs the things are not same as upper MOSFET there is no offset voltage.