超高壓變電所開關突波特性 及其對接地系統之影響研究

A Study on the Switching Surge Characteristics and Their Affections on the Grounding System in the Extra High Voltage Substation

陳子立(Zi-Li Chen)

指導教授 ： 周至如 ； 何金滿

中原大學/工學院/電機工程研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700247

摘要

本論文探討超高壓變電所接地系統之開關突波特性，針對開關突波作用下接地系統之地電位昇（GPR）、步間電壓、接觸電壓、磁場及地網導體電流進行分析，並評估它們的影響。文中首先應用電磁暫態分析程式（EMTP/ATP）建構電路模型，其中將考慮變電所之匯流排、主變壓器及接地系統，以及一次側之超高壓電源及二次側下游之特高壓輸電線及變電所負載。然後分析出現於主變壓器輸出端、輸電線、下游變電所負載及主變壓器中性匯流排接地點等處之開關突波電壓及電流。並根據注入接地系統的開關突波電流，進一步應用接地分析軟體CDEGS分析地網之地電位昇（GPR）、步間電壓、接觸電壓、磁場及導體電流，所有這些分析都將考慮開關三相同步操作及不同步操作之情形。最後基於上述分析結果，將評估接地系統開關突波特性對人員、系統及設備之影響。本研究結果顯示接地系統最危險的地點為主變壓器中性匯流排之接地點，低壓及敏感系統與設備與該點及其附近地區有關聯者，應更加注意其開關突波GPR之防護，人員亦應注意接觸電壓傷害之防護。本研究結果可對進一步研究防護措施提供更多有價值的參考資訊。

關鍵字

地電位昇 ； 超高壓變電所 ； 接地系統 ； 開關突波特性 ； 接觸電壓

並列摘要

This thesis is to study the switching surge characteristics of grounding system in the extra-high voltage (EHV) substation (E/S). The ground potential rise (GPR), ground surface potential, step and touch voltages, magnetic field and the conductor currents of ground grid due to switching surge are analyzed; and their affections are evaluated. The circuit model is first constructed by using the electromagnetic transient program/ alternative transient program (EMTP/ATP) in which the buses, main transformers and grounding system of E/S and the primary EHV source and the secondary very-high voltage (VHV) transmission lines and the down-stream substation loads are considered. Then, the switching surge voltages and currents appeared at the main transformer output, transmission lines, down-stream substation loads and the grounding points of main transformer neutral buses are analyzed. Based on the switching surge currents injected into grounding system, the GPR,
ground surface potential, step and touch voltages, magnetic field and the conductor currents of ground grid are analyzed by using a software package called CDEGS. All the analysis will consider three-phase synchronous and non-synchronous switch operations. Finally, based on the above analysis results, the affections of switching surge characteristics of grounding system on the personnel, system and equipments are evaluated. The study results had shown that the most danger points are the grounding points of neutral buses of main transformers. The low voltage and sensitive systems and equipments associated with the area near these points should be given more attentions to protect from switching surge GPR, and personnel should be protected from the damages of touch voltage. The study results can provide more useful information for further study on protection measures.

並列關鍵字

Grounding System ； Ground Potential Rise (GPR) ； Switching Surge Characteristics ； Extra-High Voltage Substation (E/S) ； Touch Voltages

參考文獻

[29] 黃鈺倫，捷運系統主變電站接地系統之開關突波特性分析，中原大學碩士論文，91年6月。

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