This paper proposes a switching pattern of a reduced switching non-isolated buck-boost DC/DC converter using series voltage compensation for a DC power interchange system. The proposed method uses a capacitor as an energy buffer in the circuit in order to reduce the current through high breakdown voltage switches. Moreover, the losses in high breakdown voltage semiconductor switches decrease. In order to estimate the effect of the proposed method, the 990W prototype is tested. In the experimental result, the efficiency of the proposed method is higher than that of the conventional method. The analysis results show that the switching loss and conduction loss are reduced using the proposed method.