Double-input single-phase six-switch-block MMC rectifier and control method thereof

The invention provides a double-input single-phase six-switch-block MMC rectifier and a control method thereof. The rectifier comprises a first alternating-current input power supply, a second alternating-current input power supply, a first inductor, a second inductor, a first bridge arm, a second bridge arm and a rectification load. Each of the first bridge arm and the second bridge arm is formed by connecting an upper switch block, a middle switch block, a lower switch block ,a third inductor and a fourth inductor in series. The upper switch blocks, the middle switch blocks and the lower switch blocks of the first bridge arm and the second bridge arm are formed by connecting N power switch units in series. The rectifier is controlled through carrier phase-shifting PWM, and the two input alternating-current power supplies are converted into two circuits of alternating current input of the 2N+1 level, rectified and overlapped and provide power for the load. In addition, the voltage stress borne by each switching tube in each MMC power switch unit is only 1/N of the voltage of a direct-current power supply, the voltage sharing problem of the switching tubes is well solved, and the double-input single-phase six-switch-block MMC rectifier is suitable for high-voltage and large-power occasions where two single-phase alternating-current power supplies are input.