Electrical rotating machine with one-sided cooling and method for one-sided cooling

The invention relates to an electrical rotating machine, comprising a stator (1), a rotor (8) and a turbomachine (7), which is provided to cool the electrical rotating machine on the one side, wherein the stator (1) comprises a laminated stator core (2), a front stator winding head (5a) and a rear stator winding head (5b), wherein the rotor (8) comprises a rear rotor winding head (6b). In order to improve cooling during the one-sided ventilation, in particular with respect to the prior art, with regard to a uniform temperature distribution, it is suggested that the laminated stator core (2) comprise channels (9a, 9b) extending in the axial direction, which are provided to cool the rear stator winding head (5b) with a second cooling air flow (14) generated by the turbomachine (7), wherein at least one first channel (9a) is provided to guide a second cooling air flow (14) generated by the turbomachine (7) through the laminated stator core (2) to the rear stator winding head (5b), wherein an air guide (4), which is fastened to the laminated stator core (2) on the side of the rear stator winding head (5b), is provided to bypass the second cooling air flow (14) via the rear stator winding head (5b), wherein at least one second channel (9b) is provided to guide the second cooling air flow (14) back from the rear stator winding head (5b) through the laminated stator core (2), wherein at least two radial slits (11) arranged in the axial direction, which are arranged radially between the channels (9a, 9b) running in the axial direction and an air gap (3) between the laminated stator core (2) and the rotor (8) and are connected to each other, are provided to cool the laminated stator core (2), in particular the stator windings, and/or the rear rotor winding head (6b), wherein the axial distance between the radial slits (11) to the side of laminated stator core (2) which faces away from the turbomachine (7) is reduced and is provided to compensate for a temperature gradient caused by one-sided cooling.