The application discloses a fault ride-through control method for a variable-frequency transformer, which comprises the following steps: first, obtaining the voltage of a first grid, the voltage of asecond grid, the voltage of a stator and the current of the stator; then, calculating the voltage reference value corresponding to a single series three-phase converter after preprocessing; and finally, converting the voltage reference value into a control signal to control the series three-phase converter. The negative sequence voltage and negative sequence current of the stator caused by the negative sequence voltage of the first grid can be restrained, and the torque and power fluctuation of double rotor angular speed and double stator synchronization speed can be eliminated. The negative sequence current of the stator caused by the negative sequence voltage of the second grid can be restrained, and the electromagnetic torque and power fluctuation of double rotor synchronization speed can be greatly reduced. That is to say, the voltage imbalance problems of the left and right grids are solved at the same time by using a single series three-phase converter. Moreover, the grid cost isreduced. The application also discloses a fault ride-through control device, a circuit controller and a computer readable storage medium, which have the same beneficial effects.