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三相不控电压源型整流装置(voltage source converter， VSC)在不同电路参数条件下，存在连续和断续两种运行状态。两种运行状态下的VSC谐波产生特性存在较大的差异。为了完整、准确地分析三相不控VSC的谐波产生特性，在已建立的VSC断续工作状态谐波模型的基础上，基于调制理论提出其在连续运行状态的频域谐波模型。该谐波模型具有和断续模型相似的矩阵形式，因此得到了三相不控 VSC的统一化谐波分析模型。模型可将VSC交流侧各次谐波电压和谐波电流的耦合关系直观地表示出来。基于VSC连续模型的推导过程，进一步提出利用VSC直流侧电流判断其运行状态的新型判据。模型和判据的计算、仿真及实验测量的结果对比验证了所提模型的准确性和判据的有效性。“,”Three-phase uncontrolled voltage source converters (VSC) have two kinds of operational modes, continuous versus discontinuous modes depending on different circuit parameters. The harmonic generating characteristics of the VSC for these two modes are very different. In order to study the harmonic generating characteristics of the three-phase uncontrolled VSC completely and accurately, a harmonic model for the converter operating in the continuous mode was proposed based on the modulation theory, following the established harmonic model for the converter operating in the discontinuous mode. Since the proposed model has a similar form as the model for the discontinuous mode, a unified analytical harmonic model was obtained. The coupling relationship between the VSC supply side harmonic voltages and its generated harmonic currents can be intuitively reflected by the unified harmonic model. Based on the derivation process of the harmonic model for the converter operating in the continuous mode, a criterion was further proposed to determine the operational modes of the VSC according to the dc currents. By comparing the results with simulations and experimental measurements, the proposed model’s accuracy and criterion’s validity were verified.