Switching Cell With Frequency Modulation for CCM Voltage-Follower Converters

This letter proposes a new switching cell with switching frequency modulation (SFM) and resistive characteristic (voltage follower) for converters that are current-fed. Soft commutation and current null (when the diode blocks) are achieved with SFM and a fixed duty cycle for converters based on this switching cell. The operating principle, a mathematical analysis of the cell, and two topological variations are presented. In addition, the basic characteristics of the main topologies are shown, and the experimental results of a 1-kW boost continuous conduction mode converter prototype are discussed to demonstrate the operating characteristics.