Implementation of open-loop control for interleaved DCM/CCM boundary boost PFC converters

This paper is focused on the implementation of the open loop control method for interleaved DCM/CCM boundary boost PFC converters where the slave converter is synchronized to the turn-on instant of the master converter and both converters operate with current-mode control. It is shown that this method is the only open-loop control method that provides a stable operation. Implementations of the master-slave synchronization circuit in both analog and digital technology are described. Experimental results obtained on a 400-W, universal input, 400-V output prototype circuit with two interleaved DCM/CCM boundary boost PFC converters controlled by an integrated control circuit currently being developed are provided.