城轨牵引系统对主变压器降容率的影响分析

Analysis of Effect of Urban Mass Transit Traction on Derating of Transformers

摘要:

以轨道交通集中供电方式为例，分别建立了交、直流2种牵引方式下的12脉波、24脉波整流供电系统模型，研究在不同牵引、整流方式下谐波电流对主变压器降容率的影响.研究结果表明，降容率随直流电阻损耗增大而减小；相比12脉波整流，24脉波整流对主变降容率影响较小；降容率随牵引负荷功率增大而减小.研究结果对轨道交通牵引系统整流器方案选择、牵引方式选择和主变压器容量确定提供了依据.

Abstract:

Models of power supply system composed by AC and DC traction modes with 12 pulse or 24 pulse rectifiers were established by taking centralized power supply in rail transit for example in order to study the effect on derating of transformers caused by harmonic currents in different traction and rectification．The study results show that the higher proportion of DC resistance losses in the total load losses of the transformer is，the lower derating rate is；24 pulse rectifier has less effect on transformer derating than 12 pulse rectifier；the larger the traction load power is，the lower the derating rate is．The results provide reference for selection of rectifier system，traction type and the main transformer’s capacity determination in urban mass transit．