本文旨在研製十二臂六相變流器之六相永磁式同步電動機的驅動系統。藉由內轉型之永磁式同步電動機的磁路及性能計算，並配合有限元素電磁場解析套裝軟體對齒槽及磁石作最佳化設計，降低反電動勢的總諧波失真率，以減少運轉時的轉矩抖動。六相永磁式同步電動機選用26極24槽之結構，額定轉速為450rpm、額定功率為1kW，感應電動勢相電壓峰值為71.07V，總諧波失真率5.02%，每相電阻為0.32Ω，交軸電感為5.7 mH，直軸電感為6.6mH。
電力電路採用十二臂六相變流器，每相繞組分接於兩臂上，形成6個單相直流-交流功率轉換器，其驅動控制採用單極性正弦脈波寬度調變，可提升系統直流鏈電壓使用率。六相永磁式電動機其中abc相或xyz相繞組中有一相故障，可以由另外二相繞組降載持續運轉，增加系統之可靠性。六相永磁式同步電動機故障控制策略藉由回授其六相電流以判斷系統故障之繞組，使系統能修正未故障之兩相電流，令未故障之兩相電流角度相差 度相位，以降低脈動轉矩，使其運轉之轉矩更為平滑穩定。本文以軟體Matlab/Simulink分析十二臂型六相變頻器與驅控六相永磁式同步電動機之系統，並完成十二臂六相變頻器之六相永磁式同步電動機驅動系統。實體製作及測試顯示本文之系統不僅可以在六相正常運轉，亦可以在abc繞組及xyz繞組的任一單相故障而作故障後的控制，由實測結果驗證控制策略的可行性。

This thesis presents the design and implementation of control system of six-phase permanent-magnet synchronous motor (PMSM) with twelve-leg six-phase inverter. Using performance calculation as well as finite element analysis, the optimum shapes of magnets, stator teeth and slots are obtained with smaller torque ripple and lower harmonic content in the back electromotive fore (EMF). A 26-pole, 24-slot six-phase PMSM is chosen. Rated speed is 450rpm. Rated power is 1kW. Peak value and total harmonic distortion of EMF are 71.07V and 5.02%, respectively. Per-phase resistance is 0.32Ω. Direct-axis and quadrature-axis synchronous inductances are 6.6mH and 5.7mH correspondingly.
The power circuit uses twelve-leg six-phase inverter. Connecting each winding to two separately controlling legs yields six-phase dc-ac power converter. The inverter control strategy uses unipolar voltage switching method to raise the utilization factor of dc-link voltage. When a winding of six-phase PMSM breaks down, the associated load may have to be reduced to retain continuous running and increase the reliability of the system. In the fault tolerance control strategy, the current of PMSM is used to determine which winding is broken, so that the other two winding currents can be corrected to result in a 60-degree angle difference, thereby reduces torque pulsation. In this thesis, Matlab/Simulink is used to simulate the proposed PMSM system including twelve-leg six-phase inverter and control system of six-phase PMSM. A prototype of control system of six-phase PMSM motor is built. Normal as well as post-fault operations are obtained as expected. The proposed system performance is thus verified experimentally.

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