Analysis of radial and tangential forces on the synchronous reluctance machine

Abstract

This article aims to analyse radial and tangential components of magnetic field and force density in the air gap of a Synchronous Reluctance Machine (SynRM). Energy is transferred between the stationary part of the electromagnetic system to the rotating part through the air gap medium. The strength and variation of the field component in the air gap determine the instantaneous torque, torque ripple, electromotive force (EMF), and undesirable radial force. To compute force and torque, different methods use either radial (Lorentz’s force (LF) method) or both radial and tangential (Maxwell stress tensor (MST) and Virtual work (VW) Methods) air gap magnetic field components. Here the finite element method (FEM) is used to solve field components. Subsequently, post-processing field components, force components are obtained using the MST method. The effect of dq currents on the radial and tangential components of the magnetic field and force density in the air gap is studied, and several observations are drawn using this analysis.