Accurate and Fast Subdomain Model for Electromagnetic Design Purpose of Wound-Field Linear Resolver

Abstract

Linear resolvers are position sensors that are being used in a wide range of applications for linear motion systems. The electromagnetic design of a linear resolver, similar to any other electromagnetic device, demands an accurate, functional, and fast tool. While the finite element method (FEM) is considered the most accurate tool for electromagnetic analysis, it is not a good candidate for an optimization-based design which is an iterative process. In this article, first off, an analytical tool based on the subdomain model is briefly presented. This model is very accurate and much faster than FEM. However, it has high computational time for iterative design and optimization processes. Therefore, in the second step, simplification assumptions are utilized to make the model even faster without compromising the accuracy of the model. In this regard, model numbers 1-4 are developed and then compared to each other in terms of computational time and accuracy. Time stepping FEM (TSFEM) is employed as the reference for comparison between different models. A prototype of the linear resolver is then fabricated to show the validity of the study. Close agreement between simulations and experimental results demonstrates the competency of the study.