Design and modeling of nanocrystalline iron core resonant transformers for pulsed power applications

A high power resonant three phase switch mode power supply has been constructed at University of Wisconsin to drive a klystron tube. Utilization of a resonant transformer with loosely coupled secondaries allows generation of high boost ratios exceeding the turns ratio while providing high efficiency. Use of nanocrystalline iron cores provides high volt seconds while maintaining low loss at high switching frequencies. Analytic models are developed and compared to measured data from two different size resonant transformers and effects of turns ratio, load resistance, and primary are examined and compared to theory.