Hz轨道电路组成和工作原理铁路信号基础设备维护课件.pptx

25Hz轨道电路组成和工作原理天津铁道职业技术学院铁路信号基础设备维护

25kv

RegionalpowergridTractionsubstationOverheadcontactsystemPantographLocomotive25kv

钢轨接触网牵引变电所送电端受电端牵引电流轨道电路电流问题1：牵引电流和轨道电流都通过钢轨传递，如何互不干扰？问题2：牵引电流如何越过绝缘节？

trackoverheadcontactsystemtractionsubstaionPowertransmissionendReceivingendTractioncurrentTrackcircuitcurrentQuestion1:boththetractioncurrentandtrackcircuithavetoflowinthetrack,howtomakethemworkreliablyandnotaffecteachother?Question2:whenthetractioncurrentmeetsinsulationjoint,howtoletitpassthejointandflowsmoothly?

牵引电流大小相等，上、下部线圈匝数相同，因此产生的磁通方向相反，总磁通等于零,对次级线圈的信号设备没有影响。相邻区段的信号电流，在两轭流变压器初级线圈中点处电位相等，信号电流不会越过绝缘节流向另一区段，而流回本区段，在次级感应出信号电流。扼流变压器信号设备扼流变压器对牵引电流阻抗很小，通过其上部和下部线圈、中心线流向相邻轨道电路，这样，牵引电流就越过了绝缘节。

Whentheamountoftractioncurrentisthesameandthecoilturnsisthesame,thedirectionofthefluxgeneratedisintheoppositedirection,sothefluxgeneratedisopposite,thetotalfluxiszero,itdoesnotaffectthesecondaryequipment.Atthemiddlepointofthechoketransformer,theelectricpotentialisthesame.thesignalequipmentisconnectedatthesecondarysideofthechoketransformer,sowhenthetractioncurrentinthetwotrackisthesame,itwillnotaffectthesignalequipmentChoketransformerSignalequipmentTheinsulationjointisusedtoseparateadjacenttrackcircuits,butinelectrifiedsection,tractioncurrenthastopassthejoint,weadoptthechoketransformer.

I1I2当I1≠I2时，牵引电流不平衡，即当△I=I1－I2存在时,扼流变压器一次侧产生的磁通不能相互抵消，在次级产生感应电压，直接侵入轨道电路。扼流变压器

I1I2WhenI1≠I2，thetractioncurrentisunbalanced,thatiswhen△I=I1-I2exists,thefluxoftheprimarycannotcounteract,atthesecondaryinducedvoltageisformedwhichaffectstrackcircuitdirectly.Inthiscase,ACtwoelementtwopositionrelayisappliedinthetrackcircuit.Weknowthatwhen50Hztractioncurrentisappliedtotrackcoil,inacycle,thetorquegeneratediszerowhichwillnotdrivethewingboardtoopera