GIS管道L型拐角、支架和盆式绝缘子的电路建模

发布时间：2018-07-29 16:03

【摘要】：GIS变电站隔离开关操作过程中会产生高幅值、宽频带的瞬态电磁波。GIS管道内部会形成特快速暂态过电压(VFTO),外部则有暂态外壳电压(TEV)。在GIS管道中存在着拐弯段、盆式绝缘子及套管等结构改变的位置,管道中的电磁波传播到这些地方时电磁场会发生局部畸变;GIS管道支架连接管道与大地,用于支撑管道,随着频率的增加,金属支架会产生集肤效应和邻近效应,其阻抗特性发生变化。正确建立管道拐弯段、管道支架及盆式绝缘子的一定频率下的等效电路模型对于管道内VFTO和外部TEV的研究具有重要意义。本文分别针对GIS管道结构拐弯段、支架和盆式绝缘子进行等效电路模型的建立。管道内电磁波传播到管道结构不规则处产生的电磁场局部畸变通常可以以集总电路元件的形式补偿到描述电磁波的传输线模型中。GIS管道中L型拐弯段可以通过由电感和电容组成的π型和T型两种等效电路进行补偿,基于电磁场仿真得到L型管道的二端口网络参数,运用传输线理论导出补偿电感和补偿电容的计算公式;对于盆式绝缘子则基于电磁场仿真得到静态电容,通过补偿电容进行等效;ANSYS Q3D Extractor软件可以提取不同结构导体一定频率下的阻抗参数,根据不同管道支架结构,建立了一种GIS管道支架宽频带阻抗近似计算方法,并验证了该方法的有效性。
[Abstract]:During the operation of GIS substation disconnector switch, high amplitude will be produced, and the transient electromagnetic wave in wide band. GIs pipeline will form very fast transient overvoltage (VFTO), and there will be transient shell voltage (TEV). Outside. There is a corner section in the GIS pipeline, the position of the structural change such as the basin insulator and the casing, etc. When the electromagnetic wave in the pipeline propagates to these places, the electromagnetic field will produce local distortion and the GIS pipeline bracket will connect the pipeline with the earth, which will be used to support the pipeline. With the increase of frequency, the metal scaffold will produce skin effect and proximity effect, and its impedance characteristics will change. It is of great significance for the study of VFTO and external TEV in the pipeline to establish the equivalent circuit model of the pipe bend section, the pipe support and the basin insulator at a certain frequency. In this paper, the equivalent circuit model of GIS pipe structure is established for the bend section, bracket and basin insulator. The electromagnetic field local distortion caused by the electromagnetic wave propagating to the irregular structure of the pipeline can usually be compensated in the form of lumped circuit elements to the transmission line model describing the electromagnetic wave. The equivalent circuit of 蟺 type and T type composed of inductance and capacitance is compensated, Based on the electromagnetic field simulation, the two-port network parameters of L-type pipeline are obtained, and the formulas of compensation inductance and compensation capacitance are derived by using the transmission line theory, while the static capacitance is obtained for the basin insulator based on the electromagnetic field simulation. The impedance parameters of different conductors at certain frequencies can be extracted by compensating capacitance with equivalent ANSYS Q3D Extractor software. According to the different pipe support structures, an approximate method for calculating the broadband impedance of GIS pipeline support is established. The effectiveness of the method is verified.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM595

【参考文献】