Application of Reset Voltage Feedback for Droop Minimization in the Unidirectional Current Pulse Transformer

This paper investigates the application of reset voltage feedback for reducing errors due to droop in the signal derived from a current transformer sensing unidirectional current pulses in switched-mode power converter applications. Droop is minimised by applying a correcting voltage in series with the transformer´s output terminals during the current pulse. The magnitude of the correcting voltage is based on the transformer´s reset voltage sensed during the power converter´s previous switching cycles. A model of the scheme is presented and a circuit is implemented. Reductions in both peak and average current droop are demonstrated.