Minimization of Cogging Force in Flat Permanent Magnet Linear Motors

Abstract

In this paper we propose a technique to reduce cogging force in linear motors by decomposing it into harmonics, finding design criteria for each component of the cogging force, and applying these different criteria to the design of the motor. The hypothesis of this approach is that single actions for reducing the cogging harmonics can be added up to reduce the whole cogging force, hence, not considering cogging force as a whole. In order to validate this technique, we present the analysis of cogging force in a Permanent magnet linear motor. Through analytical and FEM analysis of the different harmonics we present some very simple single actions to minimize radically cogging force. All this actions and the proposed technique are then validated with real tests of static cogging force with different prototypes.