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变电站开关操作在二次设备上产生的瞬态电磁干扰既有辐射干扰又有传导干扰，并具有分布性和随机性的特点，因此很难准确并系统地研究电缆终端设备的抗电磁干扰特性及其抑制措施。利用线缆集总等效电磁干扰源与终端负载无关的性质，提出了基于集总等效电磁干扰源的电磁干扰抑制分析方法。通过实验测量和计算得到的集总等效源可以研究在相同干扰源下线缆电磁干扰的抑制方法。应用实验室容性耦合夹，通过瞬态电磁场与电缆的耦合实验，验证了该方法在研究线缆瞬态电磁干扰抑制措施方面的有效性和准确性。基于实验室252kV GIS真型仿真平台实验测量了隔离开关操作在四芯屏蔽电缆两端感应的干扰电压；通过计算获得了集总等效电磁干扰源；系统研究了并联电容对电磁干扰的抑制效果。并联1 nF电容，干扰电压峰峰值减小60%。一旦获得集总等效电磁干扰源，就可以研究在该次干扰激励下任意抑制措施的抑制效能及对负载响应的影响。“,”Because the switching transient electromagnetic interference is with conduction and radiation interference and the nature of randomness and distribution in substation, it is difficult to quantitatively and systematically predict electromagnetic interference and study suppression method relative to devices connected at terminals of shielded cable. Depending on the characteristics that the lumped equivalent source (LES) is independent of the terminal load, the lumped equivalent source obtained by experimental measurements and computation can be used to study EMI suppression method under the same disturbance source. Through experiments of the transient electromagnetic field coupling with cable in lab, it was verified the effectiveness and accuracy of the model presented. Based on this model the LES was calculated using the voltage responses measured at terminal ports of four-conductor shielded cable interfered by EMI generated by disconnect operation in 252 kV GIS experiment platform. Then the suppression effect was evaluated for capacitance parallel across the terminal load. From analysis result we can see that 1nF shunt capacitance can suppress 60% of voltage response of interference. Once LES is obtained it can be used to study suppression effect of arbitrary circuit and can consider its effect on response of terminal load.