Motor train unit subsidiary loop split-phase passing uninterruptible power supply device

The invention discloses a motor train unit subsidiary loop split-phase passing uninterruptible power supply device which comprises a pantograph, a main circuit breaker, a transformer, a traction motor, a four-quadrant rectifier, a static inverter and a subsidiary current converter, wherein a subsidiary load of a motor train unit is powered from the middle direct current loop link and inverted by the subsidiary current converter; and the motor train unit subsidiary loop split-phase passing uninterruptible power supply device ensures that the subsidiary load of the motor train unit is not powered off when passing through a split phase, prevents the frequent start of the subsidiary load, improves the service life of the subsidiary load, eliminates passenger panic and other troubles caused bysuddenly powering off, and the like and improves the comfort and satisfaction of passengers.