Train power supply system and method

The invention discloses a train power supply system and method. Under the electrified railway condition, high-voltage alternating current obtained from a pantograph is converted into low-voltage alternating current through a traction transformer; power is provided for electric equipment of a train after rectification of a rectification unit, voltage stabilization of a direct current supporting capacitor, inversion of an inversion unit and isolation filtering of an isolation filtering unit; meanwhile, an alternating current provided by the isolation filtering unit can be rectified through the bidirectional rectification inversion unit to charge the storage battery pack; under the condition of no electrified railway, the storage battery pack is used for discharging, and the alternating current is provided for electric equipment of the train after inversion of the bidirectional rectification inversion unit. Continuous power supply for the train is achieved, an air-conditioning generator car does not need to be a