Single-wire current-share paralleling of current-mode-controlled DC power supplies

This paper presents a new single-wire autonomous current-share paralleling of current-mode-controlled dc power supplies. The proposed control scheme makes use of the nature of fast response of the inner current loop and the share bus injected signal to improve the response of the power supplies. It reduces the unbalance of current distribution during the transient state and avoids the fault alarm for the current limit. Through the theoretical derivation, the proposed control circuit can be designed by the three-loop control method. A design example of two 400-V/48-V 20-A parallel modules is set up and experimental recordings verify the performance of current sharing.