In power systems, high-voltage circuit breakers play an increasingly important role in providing safety protection for the grid, and therefore, the reliability requirements for high-voltage circuit breakers are very high. Currently, short-circuit interruption tests for circuit breakers are conducted at test stations, which incurs high testing costs. Conducting on-site short-circuit tests for circuit breakers is constrained by grid conditions, and each short-circuit test brings a certain impact to the power system. This results in significant limitations in terms of the number of tests and the test capacity. In this paper, a synthetic test circuit based on power electronic components is proposed. The detailed topology of the test circuit is presented, and the working principle of the circuit is explained. For the T10 short-circuit test method of the 35 kV circuit breaker, parameter calculations are carried out, and simulation verification is performed in Matlab/Simulink. The results show that this circuit can be used for synthetic testing of the 35 kV circuit breaker and meets the requirements for test equivalency.