Aiming at the defect of low voltage transmission rate of conventional three-phase-three-phase matrix converter, a multi-modular matrix converter topology is studied. In this paper, the realization process of dual-voltage synthesis modulation strategy is introduced in detail, and the division method and duty cycle expression of input side and output side are given. Then the closed-loop control strategy with output modulation coefficient as control object is proposed. In order to suppress the problem that the input current resonance caused by the input undamped LC filter affects the input performance in the closed-loop control, on the basis of the proposed closed-loop control strategy of line voltage synthesis, the original resonance suppression method using high pass filter to extract the high-frequency harmonic is improved, and the high-frequency harmonic in the dq axis component of the output load current is fed back to the output side through simple mathematical calculation. This control strategy can effectively suppress the input resonance of multi-modular matrix converter. Finally, the simulation model is established and verified by Matlab/Simulink. The results show that the improved closed-loop control strategy can effectively suppress the input resonance, and the system has good dynamic and static performance under the proposed strategy.