不同负载工况下牵引变对电网电压不平衡的影响

摘要

In view of the unbalanced voltage problem in power system caused by electrified railway accessing to public substation,A 36-node grid test system and a variety of traction transformers were established on the platform of PSCAD,and the propagation condition of unbalanced voltage caused by electrified railway was analyzed.The voltage unbalance effect on the power system when it connecting traction transformers with balanced or unbalanced load under the condition of alternation commutation phase was researched.The study finds that the rational deployment of traction load can reduce the VUF of PCC less than 2%.The research result of simulation analysis provides theoretical support and engineering application value for transformer selection and load deployment.%针对电气化铁路接入公用变电站造成供电系统电压不平衡的问题，在PSCAD平台上建立了各种牵引变压器模型及36节点的电网测试系统，分析了电气化铁路引起的电压不平衡在系统中的传播情况；研究了轮流换相的条件下多台牵引变接入对称、不对称负载时对电网电压不平衡的影响；研究发现合理调配牵引变负载能使PCC点电压不平衡度低于2％。研究结果可为牵引变的选型和负载的合理调配提供理论支撑，具有工程应用价值。