Open Search

Working with odd-turn (unequal-turn) windings

Publication date: 
July 2018
Mike Howell, EASA Technical Support Specialist
Type of media: 

Manufacturers almost always utilize machine-inserted concentric windings for random-wound, three-phase stators when their processes can facilitate it due to lower manufacturing costs. Many service centers can produce concentric windings too, but the most common practice is to utilize the two-layer lap winding. For form-wound stators, the two-layer lap winding is almost always used by manufacturers and service centers alike.

The purpose of this article is to provide some tips for working with odd-turn (unequal-turn) windings, or two-layer windings where the total number of turns per slot is an odd number (e.g., 3,5,7,9…n). In such cases, the top and bottom coil sides must have a different number of turns.

Random wound
Winding connections