Winding Design and Lead-angle Control for the Maximum Speed of an Interior Permanent-Magnet Brushless DC Motor

Abstract

This paper presents the winding design and lead angle control for the maximum speed of an Interior Permanent-Magnet Brushless DC Motor (IPMBLDCM) for the subway locomotive. The maximum speed of the IPMBLDCM is regulated by the linkage flux and armature reaction by lead angle control because permanent magnet magnetomotive force(mmf) cannot be regulated directly. The maximum speed of IPMBLDCM for the subway locomotive is 2.34 times than rated speed. As the speed regulation ratio is larger than 2, the maximum speed of the motor must be ensured by lead-angle and conductors per slot. If lead-angle is regulated, no-load speed is increased by linkage flux changing at the no-load state, and rated speed is increased by armature reaction. The relation between the speed and torque, output power, efficiency by lead angle, and conductors per slot are simulated in Ansoft Maxwell/RMxprt software. The simulation result verified that the speed and torque, output power, and efficiency are constant at the range of 47°~68° and the maximum speed is 1948r/min. Experimental results indicate that the operation of the IPMBLDCM considered is stable at the maximum speed.