Patent ID: 8242644
Filing Date: 2012-08-14
Classification: H02K,Y02E

Abstract:
1. Arrangement for cooling of an electrical machine, comprising: an outer rotor comprising a plurality of magnets; an inner stator connected via bearings with the outer rotor; the inner stator comprising a plurality of laminate plates which are connected by two end plates with the inner stator; the laminate-plates comprise a plurality of slots in which are disposed metal windings of a stator coil; the stator coil extends beyond the slots to form winding heads of the stator coil; wherein the magnets are disposed partly into an air gap which is between the outer rotor and the laminate plates; a fan arranged to circulate cooling air inside the electrical machine along a route from the fan, through a first opening through the end plates, through the winding heads, through the air gap, along the end plates, through a second opening through the end plates, through an air-to-liquid heat exchanger, and back to the fan, thus the outer rotor, the winding heads and the laminate plates are cooled and heat is transferred to the heat exchanger; where the heat exchanger is connected with a cooling liquid inlet and with a cooling liquid outlet which are used to transport cooling liquid to and from the heat exchanger, thus heat from the heat exchanger is carried away to an outer side of the electrical machine; wherein a plurality of hollow pipes are in thermal contact with the laminate plates; wherein first ends of the hollow pipes are connected with the cooling liquid inlet and second ends of the hollow pipes are connected with the cooling liquid outlet, thus a cooling circuit is formed for the cooling liquid to cool the hollow pipes and laminate plates; wherein the heat exchanger and fan are arranged within a space which is limited by the inner stator, the two end plates and the laminate plates.