Natural variable modeling and performance of interior permanent magnet motor with concentrated and distributed windings

Thesis Abstract

Interior Permanent Magnet (IPM) motor is widely used for many industrial applications and has relatively high torque ripple generated by reluctance torque. Since the configuration of the stator has great influence on reluctance torque, different stator configuration is necessary to improve the torque performance of IPM motor. Natural variable modeling and performance comparison of Interior Permanent Magnet Motor with Concentrated winding (CW), Short pitched and Full pitched distributed winding (DW) is presented in this project report. Three phase Interior Permanent Magnet Motor with identical rotor dimensions, air gap length, series turn number, stator outer radius, and axial length was studied with different stator winding configuration. Basic parameters and machine performance, such as inductances, copper losses, power density, efficiency at high and low speed, torque ripple, rotor speed with load torque, phase currents, electromagnetic torque, controllability and demagnetization tolerance are compared. As a means of supplementing analysis of the IPM motor, winding function theory (WFT) is used to analyze the motor. Winding function theory has enjoyed success with induction, synchronous, and erven switched reluctance machines in the past. It is shown that this method is capable of analyzing IPM motor with different stator configuration and the simulations were carried out by using Embedded MATLAB function. It was observed that, the concentrated winding IPM motor has a lower copper loss of 0.3 kw and 3.7 kw at low and high speed respectively and 133 Nm high peak torque developed, pull out power of 58 kw, torque ripple of 96 Nm, average torque of 142 Nm, demagnetization tolerance of 60%, amplitude of the fundamental winding is 26.45 and efficiency of 89. the short pitched distributed winding IPM motor has a lower copper loss of 0.35 kw and 3.6 kw at low and high speed respectively and 116 Nm high peak torque developed, pull out power of 57 kw, torque ripple of 71 Nm, average torque of 185 Nm, demagnetization tolerance of 78%, amplitude of the fundamental winding is 27.53 and efficiency of 87. As for full pitched distributed winding IPM motor has a lower copper loss of 0.35 kw and 3.6 kw at low and high speed respectively and 116 Nm high peak torque developed, pull out power of 56 kw, torque ripple of 71 Nm, average torque of 185 Nm, demagnetization tolerance of 78%, amplitude of the fundamental winding is 29.3 and efficiency of 88.