Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2018
Student: AHMET AKSÖZ
Supervisor: ALİ SAYGIN
Abstract:High total harmonic distortion (THD) and high cogging torque are undesirable problems in many motor applications. These problems require improvements of both motor design and driver design and control. In this thesis, a system of permanent magnet synchronous motor (PMSM) is operated with less cogging torque and less THD. Depending on the IEC 61000 and IEEE-519 international standards, the cogging torque and the system harmonics have been reduced. The PMSM mathematical model is expressed and a mechanical design with a finite element method (FEM) is made. In the analysis program, the best design for minimum cogging torque is created by using parametric optimization, MOGA, PSO and GWO methods respectively. The generated motor model is compared to the performance of rotor position of motor as axial flux and outrunner motors. Thus, using computer aided design (CAD) and analysis program, the optimum design of the motor is realized. Then, a grid connected three phase motor driver is designed. Virtual positive impedance (VPI) based active damping control (ADC) method is used for low cogging torque and low THD. A DC-link driver is designed using space vector modulation (SVM) and field-oriented control (FOC) in dSPACE DS1103 and DSP 28335. Using motor currents, speed and rotation angle (theta) in closed loop for DC-link for drive, 4 models were developed and compared. These models are weak grid without VPI without 3DSVPWM (wOVPIwO3D), weak grid with VPI without 3DSVPWM (wVPIwO3D), weak grid with VPI with 3DSVPWM (wVPIw3D) and stiff grid with VPI with 3DSVPWM (stiffwVPIw3D). Using these 4 models, the 1/Yctrl bode curve of the VPI, the DC bus voltage, the THDi of the input grid current, the cogging torque and the THDi of the motor currents are obtained, compared and discussed. Both the simulation results and the experimental results are confirmed to achieve the desired result for the solution of the problem.