As illustrated in FIGS. 2 to 6, the rotor 51 of a first embodiment includes a rotor shaft 10, a rotor core 20 supported by the rotor shaft 10, a plurality of magnetic pole portions 30, a first end plate 40a disposed on one axial end side of the rotor core 20, and a second end plate 40b disposed on the other axial end side of the rotor core 20.

The rotor shaft 10 is formed with a refrigerant flow path 11 through which refrigerant flows. The refrigerant flow path 11 extends in an axial direction inside the rotor shaft 10 and is configured such that the refrigerant can be supplied from the outside. As the refrigerant, for example, automatic transmission fluid (ATF) is used. The refrigerant flow path 11 is connected to a circulation path formed in a housing (not illustrated) which accommodates the rotating electrical machine 50.

[Rotor Core]

For example, the rotor core 20 is formed by laminating a plurality of electromagnetic steel plates formed by press working in the axial direction and joining them by swaging or bonding.

The rotor core 20 includes a rotor shaft hole 21 through which the rotor shaft 10 is inserted, a cooling portion 22 provided outside the rotor shaft hole 21 in a radial direction, and an electromagnetic portion 23 provided outside the cooling portion 22 in the radial direction.