Active starting voltage-sharing control method of bridge arm multiplexing type modularized multi-level current converter

The invention discloses an active starting voltage-sharing control method of a bridge arm multiplexing type modular multilevel converter, which relates to the technical field of flexible direct current transmission, and comprises the following steps: closing an alternating current end circuit breaker and entering a locking charging stage, and charging a capacitor by an AM-MMC through a diode. And when the capacitor voltage of the multiplexing bridge arm sub-module is charged to a preset voltage value determined by the self-adaptive voltage-sharing model through the locking charging stage, the active voltage-sharing control signal is enabled. And according to the decision of the self-adaptive voltage-sharing model, when the multiplexing bridge arm and the upper bridge arm or the lower bridge arm jointly form an equivalent upper/lower bridge arm, carrying out voltage reduction sorting and removal on the sub-modules. And continuously detecting the capacitor voltage values of the multiplexing bridge arm sub-modul