Magnetic Circuit Segmentation Effects on Fractional Slot Concentrated Winding Synchronous Machine with Grain Oriented Electric Steel

This paper presents an investigation on a fractional slot concentrated winding synchronous machine with wound rotor excitation, having different combination of non-oriented and grain oriented electric steel used for rotor poles and stator teeth and yoke. First, the effects of magnetic circuit segmentation are studied on the proposed structure with non-oriented electric steel, considering the small airgaps produced by this fabrication technique, and next, grain oriented electric steel is used for different parts of the rotor and stator magnetic circuit to evaluate the possibility of performance improvement. The purpose of this study is to find the most suitable structure for these types of machines to be build, from performance point of view, as well as material use and fabrication costs, by adopting a modular construction that reduces material wastes and increases the degree of automation of the manufacturing process.