中文摘要：

以国内±800kV特高压直流输电工程为研究背景，采用理论分析和数学推导的方法，分别研究了忽略直流输电系统换流器换相过程和考虑换流器换相过程两种情况下，换流站交流侧的特征谐波情况。同时，也对换流站直流侧的谐波情况进行了分析。在上述研究分析的基础上，以实际的±800kV特高压直流输电工程为例，采用特征谐波潮流算法和迭代谐波算法相对比的方法，对换流站交流侧和直流侧的谐波进行了计算。结果表明，利用迭代谐波算法来计算特高压直流输电工程的谐波含量是可行的。

英文摘要：

Based on the background of the domestic ±800 kV UHVDC Power Transmission Project, characteristic harmonics at AC side of converter station is researched by theory analysis and mathematical deduction, respectively, ignoring converter commutation process and considering the converter commutation process. At the same time, characteristic harmonics at DC side of converter station is researched. According to the above research, taking the actual ±800 kV UHVDC Power Transmission Project as example, AC and DC side characteristic harmonics of converter station are calculated by characteristic harmonic load flow algorithm and iteration harmonic algorithm. The result shows iteration harmonic algorithm is feasible for harmonics calculations of UHVDC transmission system. This work is supported by National Natural Science Foundation of China （No. 61074101）.