Control method for increasing efficiency of current-fed isolated bi-directional dual half-bridge converter using resonant switch

This paper proposes a new control method for a current-fed isolated bi-directional dual half-bridge DC/DC converter using a resonant switch (CF-IDHCR) to improve efficiency. CF-IDHCR is based on a current-fed half bridge converter, and the diodes bridge are replaced with MOSFETs to provide bi-directional operation. The resonant components in CF-IDHCR are used to increase the efficiency by achieving soft switching for all active switches, thus the switching loss can be reduced. However, it is difficult to increase system efficiency because of large peak current and inherent reactive power. A proposed control method, which is named by dual phase-shift control, can decrease reactive power and switch peak current, thereby system efficiency can be improved. This paper presents theoretical analysis of the proposed control method, and it is verified by a PSIM 9.1.4 simulation results.