Changeable pole three phase winding

A three phase winding for a slotted electric machine which can be changed for a pole pair ratio p.sub.1 :

• p.sub.2 = 3m :
• 2n, where p.sub.1 :
• p.sub.2 is a fractional number with aliquant integral numerator and denominator and m and n are integers, comprising:
• (a) a base winding which is formed by nine base winding branches each having the same number of series connected coils, each base winding branch having a beginning and an end;
• (b) groups of three base winding branches being connected together at their beginnings to form three phases, said connections forming the three connecting points for the pole pair number p.sub.1 = 3m;
• (c) the ends of one base winding branch from each of the groups having their beginnings connected together, being connected together to form three phases and corresponding connecting points for the pole pair number p.sub.2 = 2n;
• (d) the machine having slots which are arranged with uniform pitch;
• (e) said windings being disposed in said slots such that three coils sides which belong to the same phase for p.sub.2 = 2n and are equiphasal induced are arranged in three of the four slots which in the p.sub.2 = 2n pole pair slot-vector-star appear as vectors with the same direction and such that said three coil sides belong to different respective phase windings for the other pole pair number p.sub.1 = 3m.