ARRANGEMENT FOR COOLING AN ELECTRICAL MACHINE

摘要

The object of the invention is a cooling arrangement for an electrical machine in which a main magnetic field affects the stator and the rotor. In the arrangement, an auxiliary rotor (16, 16') is fitted onto the same shaft (8) with the rotor (6) of the machine and arranged to rotate in relation to the stator (4) and drive shaft (8) of the electrical machine. The number of poles in the auxiliary rotor (16, 16') is substantially smaller than the number of poles in the electrical machine, and a subharmonic magnetic field induced on the stator (6) of the electrical machine is arranged to rotate the auxiliary rotor (16, 16') and a fan (20) arranged to it.