A rotor design of a BLDC motor used for reciprocating compressor considering demagnetization

Abstract

This paper presents the design of a reliable rotor shape of a BLDC motor used for reciprocating compressor considering demagnetization. Three types of rotor shape are proposed for BLDC motor and a proper rotor shape is selected by characteristic analysis using the 2D finite element method (FEM). To verify the accuracy of the analysis results, a prototype was built and tested. In order to design a reliable rotor shape against the demagnetization of the ferrite magnet, the demagnetization analysis is performed according to variation of design variables of the ferrite magnet using the 2D FEM. As a result, the BLDC motor with the developed rotor shape showed good performance to resist partial demagnetization.