This paper presents the efficiency evaluation of the DC to DC Dual Active Bridge converter. Both single phase as well as three phase converters topologies have been considered in this study. Based on Dual Active Bridge DAB theoretical equations and the loss model of power semiconductor devices, full analysis of system efficiency considering various control parameters such as duty cycles, output power, and phase shifts. Simulation results are presented to validate the performance of three-phase DAB model for high power transfer considering loss model of the power converter and efficiency computation.