The invention provides an assisting and
train power supply circuit and a railway vehicle. The assisting and
train power supply circuit comprises a main
transformer, a traction
rectifier unit connectedwith the main
transformer, and a traction supporting
capacitor connected with the traction
rectifier unit; the output end of the traction supporting
capacitor is sequentially connected with a double-chopping step-down unit, a supporting
capacitor, a double-high-frequency
inverter unit, a
transformer isolation unit and a
rectifier unit; and the output end of the rectifier unit is connected with anassisting supporting capacitor and a
train power supply supporting capacitor which are mutually connected in series, the train power supply supporting capacitor is connected with a train load, and the assisting supporting capacitor is connected with an assisting load through an assisting
inverter unit and a filter unit. According to the assisting and train power supply circuit, the effect of simultaneously supplying power to the train load and the assisting load is achieved, the isolating effect of a circuit is achieved through the transformer isolation unit,
miniaturization and weight reduction of a whole circuit
system are facilitated, meanwhile, a triangular / star three-phase
isolation transformer is not adopted, thus the space is saved, and the weight is reduced.