自20世紀下半葉以來，隨著切換頻率變高的電力半導體元件之發明，電壓源轉換器在工業應用中，愈發佔有舉足輕重的地位，其中一個重要應用便是交流馬達驅動。在轉換器的實際操作中，存在諸多影響馬達驅動效能的非理想特性，例如訊號的傳輸時間導致開關切換延遲，且在同臂的開關訊號間會刻意引入怠滯時間來避免直流鏈短路；再者，開關及背接二極體的雜散電容與導通壓降也會造成電壓失真，即為實際輸出電壓與電壓命令間的誤差。轉換器非理想特性除了會產生輸出電壓誤差之外，輸出電流的總諧波失真(Total harmonic distortion, THD)亦會因而加劇，特別是低次諧波。因此，針對轉換器非理想特性的補償是極為必要的。
本論文介紹兩種補償方法，其一是將失真電壓對應電流的數值儲存起來，以查表的方式做補償；其二則是注入擬合失真電壓之梯形電壓至電壓命令，梯形傾斜角度則以消除低次電流諧波，做為目標進行閉迴路控制。
最後，以二階層轉換器連接濾波電感串聯電阻負載進行實驗，來驗證此兩種補償方法的正確性，進而比較兩者在不同操作條件下的效能。

Since the late twentieth century, the voltage source inverter has played an important role in industrial applications with the innovation of power semiconductor devices featuring higher switching frequency. One of the vital applications is ac motor drive. In practical inverter operations, there are many nonideal characteristics that influence the efficacy of motor drive. For instance, the transmission time of the signal causes the switching delay and a dead time is intentionally inserted in the gating signals of the switches of each leg to prevent the dc bus from short circuit. In addition, the parasitic capacitance and on-state voltage drop of switches and anti-parallel diodes also bring about the distorted voltage, which is the error between output voltage and voltage reference. Apart from generating output voltage error, the THD of output current also increases because of inverter nonideal characteristics, especially on low-order harmonics. Hence, compensation for inverter nonideal characteristics is indispensable.
This thesis introduces two compensation approaches. One is to store the values of the distorted voltages corresponding to the currents in a table, and make compensation by looking up the table. The other is to inject a trapezoidal voltage which is fit for the distorted voltage into voltage reference. The tilt angle of the trapezoidal voltage is to eliminate low-order current harmonics as the goal for closed-loop control.
Finally, experiments are performed with a two-level inverter connected to a filter inductor in series with a resistive load to verify the correctness of the two compensation methods, and to compare their effectiveness under different operating conditions.

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