Open AccessModular airgap windings for linear permanent magnet machines
Author(s) -
Colyer Stephen P.,
Arumugam Puvan,
Eastham John F.
Publication year - 2018
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
ISSN - 1751-8679
DOI - 10.1049/iet-epa.2017.0668
Subject(s) - electromagnetic coil , offset (computer science) , stator , conductor , magnet , engineering , control theory (sociology) , electrical engineering , finite element method , structural engineering , computer science , mathematics , geometry , control (management) , artificial intelligence , programming language
This study proposes an offset concentrated wound air‐core linear synchronous machine for launch applications where reduced supply volt‐amp per newton (VA/N) and attraction force is essential. A winding factor model based on the conductor distribution is derived and used to analyse the winding factor of possible topologies. Two configurations, 3‐coil/4‐pole and 12‐coil/14‐pole, have high fundamental winding factors and are selected for the design comparisons. Machines using single‐ and double‐sided offset windings are compared. The results obtained for these selected designs show that the 3‐coil/4‐pole design with offset winding provides the highest thrust due to its higher winding factor, but the 12‐coil/14‐pole design has lower supply VA/N. The implementation of the offset windings reduces VA/N. A significant reduction can be seen when the long stator short rotor arrangement is considered. A half‐segment prototype is built and tested. The experimental results obtained validate both the algebraic and three‐dimensional finite element analysis.