牵引变电所智能过零投切补偿系统的研究与开发

提高牵引变电所(简称牵引变)功率因数以改善系统电压质量、减少系统损耗是改善电气化铁路电能质量的有效措施。分析了我国牵引变在无功补偿和谐波治理上采用的6种方案后,采用带降压变压器的晶闸管投切电容器方案。牵引变可调并联电容补偿系统由补偿支路、采集支路和微机控制支路组成。论述了各支路的设计,该系统具有根据无功量的大小自动补偿、结构简单、工作稳定、方便等特点。通过铁路牵引供电系统的现场试验结果表明,所设计的补偿系统在正常运行时,能保证所补偿的对象全天内的平均功率因数达到0.9以上,满足电力系统要求。

Intelligent zero-cross-switching shunt capacitor compensation system in electrified railway traction substation

Increasing power factor of traction substation is the effective measure to improve power quality of electrified railway for better voltage quality and less loss. Six schemes of reactive power compensation and harmonic suppression are analyzed,based on which,the cascaded thyristor -switching capacitor compensation with step-down transformer is adopted. The adjustable shunt capacitor compensation system consists of compensation circuit,acquisition circuit and microcom-puter control circuit,and the design of each circuit is discussed. The system is simple,stable and convenient,which automatically compensates according to the reactive power variation. Field test in railway traction substation shows that,with the designed compensation system in operation,the daily mean power factor is over 0.9.