中文摘要：

结合风电运行特点，分析了风电场联络线阻抗圆动作特性，研究了风电场联络线采用传统距离保护存在的问题。建立了风电场联络线测量阻抗的数学模型，研究了运行参数对测量阻抗的影响。仿真研究了故障后风电场联络线两侧电流、电压的频谱特点及其对距离保护的影响。提出联络线采用自适应距离保护的方案。在PSCAD中构建风电场并网仿真模型，对比传统距离保护和自适应距离保护在故障时的动作特性，仿真结果表明在风电场联络线上采用自适应距离保护能够避免传统距离保护的缺陷，适应风电场多变的运行方式，消除风电场侧非工频电流、电压对保护造成的影响。

英文摘要：

Based on operation characteristic of wind farms, the acting characteristic of impedance circle of wind farm tie line iS analyzed and the existing defect of traditional distance protection adopted for wind farm tie line is researched. A mathematical model of measured impedance of wind farm tie line is built and the impact of operational parameters on the measured impedance is researched. Frequency spectrum characteristics of post-fault currents and voltages at both sides of the tie line as well as their impacts on distance protection are simulated. A scheme to protect the tie line by adaptive distance protection is proposed. A simulation model of grid-connection of wind farm is constructed by PSCAD and the acting characteristic of traditional distance protection and that of adaptive distance protection during fault are compared, and simulation results show that the defect of traditional distance protection can be avoided by adopting adaptive distance protection to wind farm tie line, besides, the adaptive distance protection can suit to various operational model of wind farms and it can eliminate the impacts of non-power frequency current and voltage on the protection.