电气化铁路对风电场影响的评估与预测

Evaluation and Forecast of Electrified Railway Influence on Wind Farm

在分析牵引负荷的负序特性以及负序对风电场运行影响的基础上,提出一种定量评估电气化铁路对风电场影响的方法,并从工程实用角度计算风电场至公共连接点(point of common coupling,PCC)的临界电气距离。将电气化铁路与风电集中接入地区电网等效为二端口网络,运用叠加原理计算多个牵引变电站接入同一上级变电站时风电场并网点的负序电压、电流,以公共连接点三相电压不平衡度达到国标限值为边界条件,计算使风电场不受负序分量影响的最短电气距离。最后,通过算例验证该方法的有效性。

Based on the analysis of the negative sequence characteristics of the traction load and the impact of the negative sequence on the operation of wind farm, this paper presents a method to quantitatively evaluate the influence of electrified railway on wind farms, and calculates the critical electrical distance from the wind farm to the PCC （ point of common coupling） from the practical angle. The regional power grid that electrified railway and the wind power access are equalled as the two-port network. It uses the superposition principle to calculate the negative sequence voltage and current of the wind farm on-grid point when there are several traction substations accessing to the same superior substation. The shortest electrical distance of the wind farm is calculated with taking the PCC three-phase voltage unbalance to the limit of national standard as the boundary condition, in which the wind farm is not affected by negative sequence components. Finally, an example is given to verify the effectiveness of the proposed method.