Improved Efficiency for an In-Wheel Motor in Large Speed Operating

Abstract

Summary form only given. A good efficiency should be a priority for every electrical machine operating within traction systems. The desired performances for each drive system are always accompanied by electro-mechanical necessities, translated in terms of high levels of power factor and efficiency. Our article proposes a synchronous motor variant with wide speed range and improved efficiency. An increased efficiency can be obtained, besides an adequate design, via a control strategy. That's why we propose a combined strategy in order to increase the motor's efficiency in wide speed operating. Up to a certain value of the excitation current we controlled the speed by controlling the d-axis current through the stator winding source and after that, we controlled the motor's speed and we obtained the flux density decrease through the auxiliary field winding. The proposed and designed motor has the following data: 5500 W, 1500 rpm, 6 pole pairs, being supplied from a 48 Vcc battery. The design process involved 2D FEM modelling and Matlab/Simulink simulation of the machine-converter system