A.C. Winding Analysis Using a Winding Function Approach

Abstract

A crucial part of every electrical machines course is the introduction to the basic elements of alternating current (a.c.) windings design. An introduction to and definition of the full-pitch coil magnetomotive force (m.m.f.) usually continues with analysis based on fundamental m.m.f. harmonics. This paper presents a winding function approach to a.c. winding analysis, which is more familiar to practising engineers than those in education. This approach has at least two principal advantages over the conventional one. First, it takes into account the exact m.m.f. waveform, i.e. all of the m.m.f. space harmonics simultaneously. Secondly, this approach is mainly computer-oriented and consequently interdisciplinary. All the basic terms in the field such as distribution factor, pitch factor, synchronous speed etc. can and are derived in this paper using a winding function definition. Additionally, basic elements of Fourier's analysis using built-in MATLAB® functions are described and its applications are illustrated.