中文摘要：

牵引负荷是一种随机波动性很大的大功率单相负荷.实践证明其对电网有较大影响,尤其是在电能质量方面.为了治理牵引供电系统带来的电能质量问题,以典型的采用三相V/V接线牵引变压器的牵引供电系统和SS9交直型电力机车为例,首先分析了三相V/V接线牵引变压器带来的谐波和负序电流的特点,然后在PSCAD/EMTDC上建立了地区电网以及牵引供电系统模型,设定具体工况进行仿真,验证并分析整个牵引供电系统对电网带来的电能质量问题,为下一步选择和设计治理方案提供依据.

英文摘要：

Traction load is a kind of large-power, single-phase load which has strong random fluctuation. It has been found that it has a great effect on the grid of Guilin district, especially in the aspect of power quality. In order to solve the power quality problems brought by tractive power supply system, a typical tractive power supply system with three-phase V/V connected traction transformer and SS9 AC/DC elec- tric locomotive is taken for example; firstly the feature of the harmonic and negative sequence current brought by three-phase V/V connected traction transformer is analyzed; and then the mode[ of the grid of a district and the tractive power supply system is built with PSCAD/EMTDC. After that specific working condition is set and then move on the simulation. The power quality problems of the grid of a district brought by the whole tractive power supply system is verified and analyzed. The results provide a basis for choosing and designing the solving scheme as the next step.