电工技术学报2016，Vol.31Issue(20)：64-72,9.
特高压气体绝缘开关设备套管的宽频等效电路建模
Broadband Equivalent Circuit Model of Bushing for Gas Insulated Switchgear in Ultra High Voltage Substation
焦重庆 1李明洋 1崔翔1
作者信息
- 1. 新能源电力系统国家重点实验室 华北电力大学 北京 102206
- 折叠
摘要
Abstract
AbstractElectromagnetic model of bushing of gas insulated switchgear (GIS) is very important for the simulation of very fast transient over-voltage (VFTO), transient enclosure voltage (TEV) and transient electromagnetic field. The VFTO can contain frequency components up to 100MHz. At such high frequencies, the length of the inner shielding conducting layer is comparable with the wavelength and hence the bushing can not be modelled as a lumped parameter element. The broadband circuit model of a gas insulated bushing with double layer shielding is investigated. The three-conductor system of bushing is modeled using transmission line theory. The influence of high order modes of electromagnetic waves excited in the discontinuities of bushing on transmission of the main mode is treated as a lumped capacitance. The two-conductor with tapered size is considered as the cascading of multiple segments of transmission lines. The electromagnetic leakage from bushing is handled with by using a radiation impedance obtained from the approximate formula. The ground capacitance parameters of top grading ring and the middle shielding layer as well as the capacitance parameter between top grading ring and the middle shielding layer are extracted respectively, by using numerical computation method. The input impedance observed at the bottom of the bushing is calculated using the circuit model of transmission line and impedance model built above within the frequency range from <br> 1MHz to 100MHz. The results from the broadband circuit model are in good agreement with those from the 3D full-wave simulations solver CST-MWS.关键词
气体绝缘开关设备套管/电磁泄漏/传输线/宽频等效电路Key words
Gas insulated switchgear bushing/electromagnetic leakage/transmission line/broadband equivalent circuit分类
信息技术与安全科学引用本文复制引用
焦重庆,李明洋,崔翔..特高压气体绝缘开关设备套管的宽频等效电路建模[J].电工技术学报,2016,31(20):64-72,9.
