基于传输线网络的特高压变电站智能组件端口电磁骚扰的建模仿真

Modeling and analysis of disturbance voltage induced on the intelligent electronic device ports based on the transmission-line network in ultra high voltage gas insulated substations

随着智能化GIS设备的发展,GIS设备上集成了大量电子设备。GIS设备开关操作产生的特快速瞬态电磁过程主要经由"传感器—二次电缆—智能组件"这段电路对电子设备产生电磁影响。笔者首先基于传输线网络理论建立了开关操作产生的地电位升对"传感器—二次电缆—智能组件"回路的耦合计算模型,然后通过验证实验证明了计算模型的有效性和准确性,最后对不同屏蔽层接地方式下的各传感器端口和智能组件各端口及端口间的骚扰电压进行了仿真研究。计算结果显示,各骚扰电压受接地方式的影响较大;通过选择合适的接地方式,可以有效地抑制开关操作电磁骚扰。

With the development of intelligent GIS equipment, a lot of electronic equipments are integrated on the GIS. The very fast transient electromagnetic disturbance （VFTED） resulted from the GIS switching operation has potential impact on the electronic equipment by the electromagnetic coupling between the VFTED and the circuit of ＂sensor-cable-intelligent electronic device（IED）＂. In this paper, a theoretical model based on the transmission-line network was established first to calculated the coupling of the ground potential rise produced by switching operations to the circuit of ＂sensor-cable-IED＂. Then the validation of this model was verified when it was used to a simple configuration. Finally, based on this model, the disturbance voltages on the sensor/IED ports and those between the IED ports were calculated and the suppression effectiveness of the grounding of the cable shield layer on the disturbance voltages was investigated. The results show that the grounding modes have great influence on disturbance voltage. By choosing the appropriate grounding mode, electromagnetic disturbance caused by switching operations can be effectively suppressed.