split mechanism 13 one is a path for driving the wheels via the reduction gear 14 the other is a path for generating electric power by driving the first motor generator 11 the first motor generator 11 is a three phase ac rotary electric machine that includes a u phase coil a v phase coil and a w phase coil the first motor generator 11 generates electricity by the motive power of the engine 10 divided by the power split mechanism 13 the electric power generated by the first motor generator 11 is used for different purposes depending on the traveling state of the vehicle or the state of charge soc of the driving battery 15 for example when the vehicle is traveling in the usual state the electric power generated by the first motor generator 11 is used directly as the electric power for driving the second motor generator 12 on the other hand when the soc of the driving battery 15 is lower than a predetermined value the electric power generated by the first motor generator 11 is stored in the driving battery 15 when starting the engine 10 the first motor generator 11 functions as a motor and cranks the engine 10 during cranking the.