A new surface-inset, permanent-magnet, brushless DC motor drive for electric vehicles

Abstract
A new five-phase, surface-inset, permanent-magnet (PM), brushless DC motor drive is proposed in this paper. The motor drive has advantages of both the PM brushless DC motor drive and the DC series motor drive. The originality is that the air-gap flux of the motor is generated by both the PM excitation and the specially controlled stator currents (two particular phases) under the same PM pole. The motor configuration and principle of operation are so unusual that the magnetic field distribution and steady-state performance are analyzed by the finite-element method. Experimental results for a prototype verify that the proposed motor drive is promising for modern electric vehicle applications.