Calculation of a Lap Winding Coil Geometry

The subject of this contribution is a description of accurate numeric calculation of a lap winding coil geometry, in particular preformed coil for armature winding. A method of calculation of the geometry in cylindrical coordinate system is proposed and it considers both radial extension of winding overhangs as well as bevelling of winding overhang loop. The results obtained by proposed calculation are compared with fifteen samples of coils used in mass produced traction machines, whose coils are manufactured with both mentioned modifications – radial extension of winding overhangs and bevelling of the coil loop.