Traction system for motor train unit hybridly powered by overhead contact system and power pack

Disclosed is a traction system for a motor train unit hybridly powered by an overhead contact system and a power pack, which system comprises a traction transformer, a power pack, a traction convertor, a traction motor, a brake resistor, etc., wherein a primary winding of a traction transformer is connected to the overhead contact system via a pantograph; two secondary windings of the traction transformer are directly connected to the traction convertor; the traction convertor is connected to the traction motor; and a diesel engine and a generator constitute the power pack, and three phase outputs of the generator are directly connected to the traction convertor. The system can operate both on an electrified railway and a non-electrified railway. In a non-electrified section of railway, the mode of power supply of a power pack is adopted, thereby achieving the normal operation in the operating condition of the overhead contact system. The motor train unit has the functions of emergency rescue and combat readiness in special rainy and snowy weathers or in the condition where the overhead contact system is damaged.