Electric motor with bar winding and connection plates

A method for assembling a multiphase synchronous electrical machine for converting kinetic energy into electrical energy and electrical energy into kinetic energy on board a transport vehicle;

• wherein the electrical machine comprises a rotor, extending along an axis, and a stator, which is provided with a stator pack having slots set substantially parallel to the axis and with an electrical winding, which extends in part in the slots and in part in a position corresponding to two heads arranged on opposite sides of the stator pack and comprises bars housed in the slots and connected to one another in a position corresponding to the heads, each of the bars having two opposite end faces and a respective length, the method comprising:
• packing connection plates to one another and to the stator pack in an axial direction so as to define a prolongation of the stator pack, each of the connection plates having two substantially parallel faces set substantially traverse to the axis that define a thickness therebetween;
• arranging the bars such that each of the two opposite end faces of each of the bars are set substantially flush with one of the substantially parallel faces of a corresponding one of the connection plates packed to the stator pack;
• and
• welding the connection plates to the bars.

A winding of a multiphase electric motor, comprising:

• a plurality of bars having opposite ends and arranged substantially parallel to an axis, the plurality of bars divided into groups of different lengths;
• a plurality of connection plates welded to the opposite ends of the bars and being stacked one against another in two opposite groups in an axial direction, each of the connection plates having a substantially constant thickness and an average radial height;
• wherein the thicknesses of the connection plates vary according to an axial position of the connection plates between a maximum value at least near a stator pack to a minimum value at least near a free end of a head;
• and
• wherein the average radial heights of the connection plates vary according to the axial position of the connection plates between a maximum average height at least near the free end of the head and a minimum average height at least near the stator pack.