為了響應對中高功率趨勢的不斷增長的需求，多級電壓源轉換器（voltage source converters, VSCs）成為了一大研究目標。其中一種廣泛使用的VSC是二極體箝位多級轉換器（diode-clamped multilevel voltage source converter, DCM-VSC）。隨著電網中轉換器的增加，它們的諧波影響可能互相影響。儘管如此，目前的文獻缺乏DCM-VSC的諧波模型。在本文中，推導出了可以反映出輸入與輸出諧波的DCM-VSC的ABCD矩陣。由於矩陣使用時間域模型，因此輸出諧波非常精確，不會受到計算諧波的次數影響。推導出的ABCD矩陣可以很輕易地應用到微電網中，當微電網受到各種不平衡條件的影響時，此模型也可預測所有的非特徵諧波。本文除了所有結果與PSCAD / EMTDC驗證的結果之外，所提出的方法的計算時間相比要短得多。

In response to the growing demand for medium and high power trends, multilevel voltage source converters (VSCs) have been attracting growing considerations. One of the widely used VSCs are the diode clamped multilevel VSC (DCM-VSC). As these converters proliferate, their harmonic impact may become significant. Nevertheless, a harmonic model for the DCM-VSC is currently lacking in the literature. In this paper, the ABCD matrix, mapping the input harmonics to the output harmonics of DCM-VSC is derived. As the matrix is formulated in the time-domain, the output harmonics are exact and do not suffer from harmonic truncation errors. As the paper will demonstrate, the derived ABCD matrix can be easily applied to a microgrid system and users can easily predicts all the uncharacteristic harmonics when a microgrid is subjected to various conditions of imbalance. In addition to all the results being validated with those of PSCAD/EMTDC, the computation time of the proposed method is in contrast much shorter.

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