Abstract: In recent years, high-voltage and large-capacity DC/DC converters have received more and more attention as the key equipment for voltage conversion in the DC grid. This paper presents a high-voltage large-capacity DC/DC converter integrated with the function of DC circuit breaker, which uses the control of the converter itself to realize the function of blocking DC-side short-circuit faults, and has the advantages of simplicity, low cost and high efficiency. At first, this paper conducts a comprehensive analysis of the topology structure and operation principles of the converter, and deduces the parameter design basis for sub-modules, thyristors, diodes and other devices. And then, the mechanism for blocking sub-modules and thyristors is proposed to block the fault current, and the control schemes of the converter are also designed. Besides, simulations and experiments are carried out for normal conditions and fault conditions, and the results have verified the effectiveness of the topology structure and control schemes. Finally, through a comparative analysis with other typical DC/DC topologies integrated with the function of DC circuit breaker, the technical and economic efficiency of the proposed converter is evaluated.