Analysis of a feedback-based current clamp minimisation technique

Current clamp is a term that describes the current staying at zero for extended periods of time upon current direction reversal in a inverter driven load. It is caused by the dead-time in the inverter that is required to prevent current shoot-through. Traditional PI controllers have difficultly eliminating this effect as very high gains are required which result in instability. This paper analyses an approach using augmented feedback in the dead-time region to minimise current clamp with PI controllers.