变电站开关操作对屏蔽电缆电磁干扰的预测

研究变电站瞬态电磁场对屏蔽电缆的电磁耦合问题，对于提高变电站内二次设备的抗电磁干扰能力具有极为重要的意义。文中将矩量法与传输线理论相结合，应用场线耦合理论计算变电站开关操作产生的空间电磁场对站内屏蔽电缆的电磁干扰。通过与国际上通用的电磁暂态计算程序EMTP的计算结果进行比较，验证了计算方法的正确性，同时克服了EMTP只能处理屏蔽电缆与母线平行放置的不足。最后，将该计算方法应用于500kV变电站开关操作时，在屏蔽层不同接地方式的屏蔽电缆上产生的电磁干扰的数值预测，获得了一些有益的结论，可为工程应用提供一定的理论依据。

Prediction of Electromagnetic Interference on the Shielded Cable Due to the Switching Operation in Substation

It is of great significance to study the electromagnetic coupling of the transient electromagnetic field to shielded cable for improving the electromagnetic anti-interference ability of the secondary equipments in substation.Based on the hybrid method of method of moment(MoM) and transmission line method,the field-line coupling theory is used for predicting the electromagnetic interference(EMI) on the shielded cable due to the switching operation in substation.Compared with the results of EMTP,the proposed method is proved to be correct.Furthermore,this method overcomes the disadvantage of EMTP,which is only applicable for transient analysis of parallel conductors.At last,this method is applied to numerical prediction of EMI on the shielded cable,whose shield is grounded by different modes,due to the switching operation in 500kV air insulation substation(AIS).And some beneficial conclusions are obtained,which are the theoretical foundation of practical engineering application.