a drive train for an automatic transmission for an electromechanical hybrid vehicle is disclosed . the drive train is designed as a whole consisting of only 29 major parts and units , capable of generating 6 forward shifts and 1 reverse shift . a motor is wholly arranged on an input shaft such that the rotation speeds of the motor and the input shaft are synchronous . the motor has the functions of an electric generator and can drive a vehicle to run by a reactive force generated by the magnetic field of the electric generator such that the vehicle generates power during running and therefore avoids consuming the power of the engine due to the load of the electric generator , and thus , the aim of power conservation is achieved . in the hybrid drive mode , the vehicle does not need a clutch and a brake to shift the gear at the moment of startup and during running and therefore realizes stepless transmission and can transmit a large torque .