Analysis and Design of a Single-Phase Half-Bridge Rectifier With an Active DC Bus

This paper introduces the concept of an active DC. The active DC bus consists of a reduced passive DC bus and an Active Resonant Voltage Balancer (ARVB). The ARVB, operating as a series resonant converter, reduces the DC bus current ripple by injecting balancing current into the DC bus mid-point. This injected current effectively counteracts the fundamental component of the current flowing to the mid-point of the DC bus, resulting in a significant reduction in both the gravimetric and volumetric volume of the DC bus. The proposed concept is thoroughly analyzed through a case study involving a single-phase half-bridge rectifier application. Through theoretical analysis and experimental validation, the usefulness and feasibility of the proposed concept are demonstrated, showing in the presented case study a reduction of the DC bus volume by a factor of 4 at the expense of an increase in losses. The concept represents a viable option in power conversation applications where volume and weight reduction and optimization are required.