Multiphase ZVS Active Clamp Boost Converter: DC and Dynamic Current Sharing

The active clamp boost converter (ACBC) has been analyzed, and a complete model has been obtained. It has been checked that it behaves as a voltage source with high input impedance. Because of this feature, this topology is suitable for multiphase design, where different stages share the load in a passive way, without any extra mechanism or components. The design of multiphase converters is simplified, particularly for a big number of phases, as no extra information must be processed. Steady-state current sharing has been studied as well as how component tolerances affect the current distribution. A simple design guide to select different components has been detailed, and, moreover, the conditions to achieve soft switching have been revised. To test passive current sharing, a two-phase ACBC has been built. It has been tested in open loop to prove that without any control loop or extra components, the load sharing is achieved.