開關磁阻馬達之驅動特性及轉矩產生能力受許多關鍵因素之影響，如線圈電流波形、換相激磁行為及動態控制。本論文旨在建構一具前端轉換器之數位訊號處理器為主開關磁阻馬達驅動系統，及從事換相控制策略研究以改善其驅動特性。一般認知，直流鏈增壓是改善馬達於高速驅動下線圈電流響應之最佳方法。□達此目的，本論文開發出一置於馬達驅動器及電池間之前端直流轉換器，除增壓外，此轉換器也可操控成降壓式切換式整流器對電瓶充電。在兩個工作模態下之電路及控制器分析與設計於文中均有詳細說明。實測結果顯示所設計之前端轉換器可從事動態增壓而增進線圈在高速下之電流響應，進而增進馬達之速度動態響應特性。而此前端轉換器操作於切換式整流器時，亦可得到良好之輸出電壓調節特性及線電流入電電力品質。
而在換相調控的研究上，本論文提出三種換相控制的方法，包含截止角固定導通角前移；導通角固定截止角後移；及導通角與截止角同時前移等。對於所有的調控方法，均詳細從事其理論之分析推導、調控機構之設計與實現、以及實測之效能評估。最後由所得之分析及實測經驗，研擬ㄧ自動調控技巧以等值得到開關磁阻馬達之最大轉矩/電流比。
而在速度控制之改善研究上，由步級響應法估測得到開關磁阻馬達驅動系統於正常工作情況下之動態模式。接著研擬一具雙可調度之速度控制機構，其係由一比例積分□授控制器及一強健擾動前向控制器所組成。□授控制器先設計以滿足所欲之命令追蹤響應，而負載擾動及系統參數變化效應由強健控制器調控。結果顯示所設計之速度控制器具有良好之命令追蹤及負載調節特性，且所得性能具有強健性。

It is known that the driving performances and torque generating capability of a switched reluctance motor (SRM) are significantly affected by many key factors, such as winding current waveform, commutation behavior and dynamic control. This thesis is mainly concerned with the development of a DSP-based SRM drive with front-end converter and its driving performance improvement via commutation controls. As generally recognized, DC-link voltage boosting is the most effective means in improving the winding current response during high speeds. To achieve this, a front-end DC/DC converter placed between battery and SRM drive is developed in this thesis. In addition to voltage boosting, this converter can also be operated as a buck-type switched-mode rectifier (SMR) to charge battery. The analysis and design of the convert circuits and control schemes in two operation modes are all performed in detail. The experimental results show that the winding current and speed dynamic response in high speeds can be much improved via the dynamic voltage boosting by the developed converter. And the SMR can also be normally operated with satisfactory performance in voltage regulation and line drawn current power quality.
As to the commutation tuning control, this thesis performe the studies about three commutation instant tuning controls, including altered and fixed, fixed and receded, and and altered simultaneously. For all control approaches, the theoretical analysis, the tuning scheme and the experimental performance evaluation are all made. According to the analysis and experimental results, a heuristic algorithm is employed to find the optimal commutation advanced angle for achieving maximum torque per ampere equivalently.
In treating the speed dynamic control, the dynamic model of the established SRM drive is first estimated at a chosen operating point. Then a 2DOF control scheme, consisting of a PI feedback controller and a disturbance robust feedforward controller, is designed and applied to let the SRM drive possess the quantitative and robust speed dynamic responses both in tracking and load regulation controls.

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G. Current Profiling
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H. Front-End Converter
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