地铁降压变电所负荷情况实测与评估

Measurement and Evaluation of the Load Process at Metro Step-down Substation

以成都地铁部分降压变电所为例,对其负荷进行了实测分析。35 k V/400 V降压变电所变压器大都处于轻载状态,其负载率为6%~22%;其400 V母线电压总谐波畸变率的95%概率值均小于5%,谐波电流含量多为19~95 A。降压变电所各类负荷中,环控和冷源负荷耗电量最大,分别占总耗电量的31%及24%。环控负荷是降压变电所内较大的谐波污染源。对地铁降压变电所负荷情况的测试及分析,可为变压器容量和有源滤波装置的设计提供合理建议。

The load of a step-down substation in Chengdu metro is tested and analyzed.It shows that most of the transformers in 35 kV/400 V step-down substations are in the light load condition,the load rate is about 6%~22%.For 400 V buses,the 95%probability values of the total harmonic voltage distortion are all lower than 5%,the content of the harmonic current is about 19 A^95 A.Among all kinds of load in step-down substations,the load proportions of environmental control and cold source are the biggest,accounted for 31%and 24%respectively,the environmental control load is considered as the larger harmonic source.The power quality test and analysis of the power load in metro step-down substation can provide reasonable suggestions for the design of transformer capacity and APF(active power filter).