Research On Electromagnetic Interference Of Lightning To The Secondary Cable Of Substation

With the increase of voltage class and the development of smart grid,secondary systems and communication equipments in plants and substations are playing more and more important roles.The electromagnetic compatibility problems of substations become more essential and more complex.The secondary cable of substation may cause damage,maloperation or miss trip of facilities when suffering electromagnetic interferences.Thereby serious security problems may be triggerd.Therefore,it is essential to study the electromagnetic interferences on secondary cable of substation.It is important to study the law of the electromagnetic interferences on secondary cable of substation caused by lightning strike which is a serious kind of interference sources.Combined with the project of Sanmenxia Power Supply Company,Various electromagnetic interference sources in substations are systematically analysised in this paper.Then,the electromagnetic interferences on a secondary cable in a substations in China are studied.Lightning intruding over-voltage,space radiation caused by high frequency oscillation of the bus and interference voltage on port of control cable after ground grid occurred lightning stroke are calculated.are calculated.Lightning intruding over-voltages caused by back striking are calculated by ATP-EMTP.Electromagnetic interferences on a control cable are calculated by CDEGS,which is a general calculating program.After that the interrelated factors of the interference voltage are studied,which include the length and layout of the cable,the position of lightning strike spots etc.The results of this paper have great value on the design of substations and the selection of facilities.