一般而言，欲實現永磁同步馬達的驅動控制，需要有馬達轉子的位置資訊，但加裝位置感測元件容易導致系統成本與裝置體積增加，且位置感測元件大都對於溫度與環境的變化較為敏感，導致在某些特殊應用場合中的可靠度不佳。為解決此問題，本論文針對永磁同步馬達驅動器開發出一泛用型無轉子位置感測器驅動技術。本論文提出基於等效反電動勢數學模型的滑動模式電流觀測器，藉由觀測器估測之反電動勢資訊，間接求得永磁同步馬達之轉子位置及速度。本論文所提出之滑動模式電流觀測器有良好的收斂速度，且估測之轉子位置資訊準確，並可使用於廣泛的轉速區域。尤其甚者，等效反電動勢數學模型僅需輸入馬達之相電阻與交軸相電感值即可，使本論文所提出之方法容易實現於低成本微控制器。此外，具備電子煞車功能之永磁同步馬達驅動器，不僅可使馬達在減速時有良好的速度響應，且可回收減速過程中的動能，增加能源的使用效率。在僅使用基本的永磁同步馬達驅動器電路架構下，本論文藉由改變功率元件的切換策略，實現三種適合不同煞車時機之無位置感測器式電子煞車切換策略，並針對最大升壓比、制動力矩等重要的電子煞車性能指標以進行分析討論。最後本論文藉由理論分析、並進行數個實驗與不同的應用，以驗證所提方法之可行性，實驗結果顯示本論文所提出之無位置感測器式磁場導向控制與電子煞車換相方法可適用於各種調速應用場合。

Generally, in order to implement the drive control of the PM synchronous motor, the rotor position information is essential. However, position sensors may increase the cost and volume of the motor system due to the extra components and wiring. Moreover, most position sensors are sensitive to change in ambient temperature. As a result, the reliability of the position sensor based approach is far from satisfactory in some specific applications. In order to alleviate the above problem, this dissertation develops a general purpose position sensorless method for PM synchronous motor drives. This dissertation proposes a sliding-mode current observer based on a general purpose equivalent back-EMF model. By using the back-EMF estimated from the sliding-mode current observer, one can indirectly obtain the information of the angular position and velocity of the rotor. The estimated rotor position is accurate, and fast convergence of the observer is guaranteed over a wide speed range. Moreover, only stator resistance and stator inductances in the q-axis are essential to the calculation of the general purpose equivalent back-EMF, which is easy to implement in low-cost microcontrollers. In addition, the drives of PM synchronous motors capable of electric braking not only allow the motors to smoothly decelerate to a soft stop, but also can recover kinetic energy so as to improve the efficiency of energy consumption. In order to conduct an in-depth study on this topic, this dissertation analyzes and implements three possible position sensorless electric braking commutation strategies based on a general full-bridge motor drive without any additional power switches and bulky passive components. For the position sensorless electric braking commutation strategies, theoretical analysis on different performance indices such as maximum voltage conversion ratio, braking torque, energy recovery ratio, etc., are carried out and compared among each commutation strategy. Finally, theoretical analysis, several experiments and various applications are performed to verify the effectiveness of the proposed methods. Experimental results indicate that the proposed position sensorless FOC and electric braking commutation methods are suitable for various speed regulation applications.

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