發(fā)布時(shí)間：2018-09-17 16:47

【摘要】：小電流接地系統(tǒng)是國(guó)內(nèi)外非常流行的一種接地系統(tǒng)。目前常見(jiàn)的小電流系統(tǒng)都是以接地方式的不同而作區(qū)分的,而最常使用的接地方式主要有經(jīng)電阻接地、經(jīng)消弧線圈接地以及不接地三種。目前我國(guó)的小電流接地系統(tǒng)主要使用于3-66kV的電力系統(tǒng)中。這主要是因?yàn)樾‰娏鹘拥叵到y(tǒng)在遭遇故障的時(shí)候仍然能維持一段時(shí)間的正常運(yùn)行,因此被廣泛使用。我國(guó)的6~66kV配電網(wǎng)電力系統(tǒng)多屬于小電流接地系統(tǒng),一般采用中性點(diǎn)不接地或者中性點(diǎn)經(jīng)消弧線圈接地的工作方式,因其發(fā)生接地故障時(shí),流過(guò)接地點(diǎn)的電流小,又稱(chēng)中性點(diǎn)非有效接地系統(tǒng)。接地故障是指由于導(dǎo)體與地連接或?qū)Φ亟^緣電阻變的小于規(guī)定值而引起的故障。根據(jù)電力系統(tǒng)運(yùn)行部門(mén)的故障統(tǒng)計(jì),由于外界因素(如雷擊、大風(fēng)、鳥(niǎo)類(lèi)等)的影響,配電網(wǎng)單相接地故障是配電網(wǎng)故障中最常見(jiàn)的,發(fā)生率最高,占整個(gè)電氣短路故障的80%以上。當(dāng)發(fā)生單相接地故障時(shí),由于不能構(gòu)成低阻抗的短路回路,接地電流很小,故稱(chēng)為小電流接地系統(tǒng)。它的優(yōu)點(diǎn)在于發(fā)生單相接地故障時(shí)多數(shù)情況下可以自動(dòng)熄弧并恢復(fù)絕緣。當(dāng)線路發(fā)生永久性單相金屬接地故障后,三相系統(tǒng)的線電壓仍然是對(duì)稱(chēng)的,大小與相位并不變化,但系統(tǒng)的接地相對(duì)地電容被短接,對(duì)地電壓都變?yōu)榱恪�為防止另一相在接地而引起兩相短路甚至三相電�?因而必須限制一定時(shí)間內(nèi)排除單相故障。本文致力于解決小電流接地系統(tǒng)在遭遇故障的時(shí)候減小對(duì)電力系統(tǒng)的損害問(wèn)題。通過(guò)深入分析系統(tǒng)發(fā)生故障的原因,從而在源頭上找到避免故障發(fā)生的辦法。為此,計(jì)劃進(jìn)行下述工作:(1)研究中性點(diǎn)接地各種方式的特點(diǎn)。(2)進(jìn)行小電流單相接地系統(tǒng)的故障分析。(3)電力系統(tǒng)短路故障分類(lèi)與計(jì)算。(4)進(jìn)行小電流接地系統(tǒng)故障仿真分析。
[Abstract]:Low current grounding system is a very popular grounding system at home and abroad. At present, the common small current systems are differentiated by different grounding modes, and the most commonly used earthing methods are mainly through resistance grounding, arc suppression coil grounding and non-grounding. At present, the small current grounding system in China is mainly used in the power system of 3-66kV. This is mainly due to the low current grounding system can still maintain normal operation for a period of time in the event of failure, so it is widely used. The power system of 6~66kV distribution network in our country mostly belongs to the small current grounding system. Generally, the neutral point is not grounded or the neutral point is grounded by the arc-suppression coil, because the current passing through the connection place is small when the grounding fault occurs. Also called neutral point non-effective grounding system. Grounding fault refers to the fault caused by the connection of conductor to ground or the change of insulation resistance to ground less than the specified value. According to the fault statistics of power system operation department, because of the influence of external factors (such as lightning strike, strong wind, bird and so on), the single-phase grounding fault of distribution network is the most common fault and the highest incidence. It accounts for more than 80% of all electrical short-circuit faults. When a single-phase grounding fault occurs, it is called a small current grounding system because it cannot form a short circuit with low impedance and the grounding current is very small. Its advantage is that it can automatically extinguish the arc and restore the insulation when the single-phase earth fault occurs. After the permanent single-phase metal grounding fault occurs, the line voltage of the three-phase system is still symmetrical, and the magnitude and phase of the system are not changed, but the grounding capacitance of the system is short-connected and the voltage to the ground becomes zero. In order to prevent the other phase from causing two phase short circuit or even three phase circuit in grounding, it is necessary to limit the single phase fault within a certain time. This paper is devoted to solving the problem of reducing the damage to the power system when the small current grounding system is in trouble. Through in-depth analysis of the causes of system failures, to find ways to avoid failures at the source. Therefore, the following works are planned: (1) study the characteristics of neutral grounding modes; (2) carry out fault analysis of single-phase earthing system with small current; (3) classify and calculate short circuit faults of power system; (4) carry out fault simulation analysis of low current grounding system.
【學(xué)位授予單位】：湖北工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TM862

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 黃娟娟;;35kV電網(wǎng)小電流接地系統(tǒng)單相接地故障選線[J];通訊世界;2017年03期

2 單汝濤;喬險(xiǎn)峰;劉聰;陳廣澤;;小電流接地系統(tǒng)單相接地選線方法之我見(jiàn)[J];通訊世界;2017年02期

3 彭泓;楊巍;;基于EEMD和關(guān)聯(lián)維數(shù)的小電流接地故障選線方法[J];測(cè)控技術(shù);2017年01期

4 徐振;許明;汪洋;夏煒;杜向楠;;基于粒子群聚類(lèi)算法的小電流接地系統(tǒng)故障定位方法研究[J];電氣應(yīng)用;2017年01期

5 薛永端;薛文君;李娟;徐丙垠;;小電流接地故障暫態(tài)過(guò)程的LC諧振機(jī)理[J];電力系統(tǒng)自動(dòng)化;2016年24期

6 史運(yùn)鋒;;小電流接地系統(tǒng)中性點(diǎn)接地裝置選型應(yīng)用[J];機(jī)電信息;2016年36期

7 羅浩杰;張棟柱;李民強(qiáng);玉聰;王勇軍;;基于人工神經(jīng)網(wǎng)絡(luò)小電流接地選線方法研究[J];四川電力技術(shù);2016年06期

8 陳錦攀;;配電網(wǎng)小電流接地系統(tǒng)故障的文獻(xiàn)計(jì)量分析[J];科技創(chuàng)新與生產(chǎn)力;2016年12期

9 嚴(yán)功門(mén);;小電流接地系統(tǒng)故障定位技術(shù)探析[J];工程技術(shù)研究;2016年07期

10 杜向楠;盧敏;馮偉崗;王偉濤;;小電流接地故障定位測(cè)距一體化研究與實(shí)現(xiàn)[J];電工技術(shù);2016年11期

相關(guān)碩士學(xué)位論文 前4條

1 陳素玲;配電網(wǎng)規(guī)劃中電力需求預(yù)測(cè)方法的研究[D];湖南大學(xué);2014年

2 楊修宇;基于負(fù)荷密度指標(biāo)的空間負(fù)荷預(yù)測(cè)方法研究[D];東北電力大學(xué);2014年

3 孫威;基于負(fù)荷密度指標(biāo)法的配電網(wǎng)空間負(fù)荷預(yù)測(cè)方法研究[D];重慶大學(xué);2010年

4 袁紹山;配電網(wǎng)規(guī)劃中負(fù)荷密度指標(biāo)確定和中壓配電電壓等級(jí)優(yōu)選研究[D];上海電力學(xué)院;2010年

，

本文編號(hào)：2246528