3-Phase PM Synchronous Motor : High Speed with Low Torque

Abstract

The objective of this project was to design a 3-phase PM Synchronous motor with a constant speed at a specific frequency value supplied from a variable frequency drive (VFD) source. The thesis explains in de-tail the effect of varying the frequency values supplied from the VFD system on the motor’s speed. This study also aims for determining the torque-speed characteristic curve of this motor and analysing some of the importance and advantages of synchronous motors over induction motors.

The success of this project was enabled by first calculating values for all important parts of the motor. These include the stator and rotor lengths, total slots, diameters, number of poles, current density and more by the use of MATHCAD program which gave way for the successful realization of the main parameters needed for the motor’s setup. By using the variable frequency drive (VFD) unit, it was easy to vary the out-put voltage and supply frequency to suitable values so that the motor runs at a constant speed.

A 3-phase PM Synchronous motor was designed in accordance with the requirements and objectives of the thesis. The theoretical standard of this project was reached successfully by comparing its main features to that of already existing synchronous motors having similar datasheets. Thus, the study shows a unique and clear functional pattern in the manner of operation, table of values, synchronized speed, power factor im-provement, high efficiency when compared to that of existing PM synchronous motors.