安(ān)科(kē)瑞 陳(chén)聰(cōng)

Application of insulation monitoring of IT distribution system in mine

摘(zhāi)要(yào)：能源作(zuò)為(wéi)經濟發(fā)展的重要引擎(qíng)，堪(kān)稱是國民經(jīng)濟的命脈。采礦業(yè)一(yī)直是(shì)能源(yuán)工業(yè)的重要支柱(zhù)，我國(guó)的礦(kuàng)業(yè)生(shēng)產(chǎn)主要來(lái)自(zì)井下開采(cǎi)，環境(jìng)惡劣，就以煤(méi)礦為(wéi)例(lì)，煤礦井下(xià)存在水(shuǐ)，火，瓦斯(sī)，煤塵，頂板五(wǔ)大自(zì)然災害，加上生產(chǎn)環境復(fù)雜，易發生惡(è)性(xìng)事(shì)故(gù)。出(chū)於(yú)安全考(kǎo)慮，礦山(shān)井下低(dī)壓配電係統按(àn)規定(dìng)采用的(dí)是IT係統。IT係(xì)統就(jiù)是電源中(zhōng)性(xìng)點不(bù)接(jiē)地(dì)，用(yòng)電設(shè)備外露(lòu)可導(dǎo)電部(bù)分(fēn)直接接(jiē)地(dì)（PE綫）的(dí)係統(tǒng)。IT係(xì)統的特點(diǎn)是發生第(dì)①次(cì)接地故(gù)障(zhàng)時，接地故(gù)障電(diàn)流僅為(wéi)非(fēi)故障(zhàng)相對(duì)地(dì)的電容電流(liú)，其值很(hěn)小(xiǎo)，外露導電部分對(duì)地電壓(yā)不超(chāo)過(guò)50V，不需(xū)要(yào)立即切(qiē)斷故(gù)障(zhàng)回路，因(yīn)此(cǐ)可以(yǐ)保證供(gōng)電(diàn)的連(lián)續(xù)性(xìng)。但(dàn)此時(shí)非故障(zhàng)相對(duì)地電壓會(huì)升(shēng)高1.732倍，對綫路耐壓要(yào)求(qiú)提升；同時一旦發(fā)生(shēng)二(èr)次接地(dì)，則構成危(wēi)險的相間短路(lù)，所(suǒ)以須配置(zhì)絕緣監測裝置，以(yǐ)便在(zài)發生第①次接地(dì)時(shí)就要及時排(pái)除隱患(huàn)。而對於以(yǐ)煤(méi)礦(kuàng)為典型(xíng)代(dài)表的井下(xià)環境來說，在(zài)開采過程中，由(yóu)於工作場(cháng)所(suǒ)空(kōng)間小，縱深長(cháng)，加(jiā)上(shàng)空氣潮濕(shī)，多塵，巷(xiàng)道(dào)滴(dī)水(shuǐ)和積水(shuǐ)等諸多惡劣因素，很(hěn)容易引起(qǐ)電(diàn)纜和(hé)電(diàn)氣(qì)設(shè)備(bèi)老化和(hé)絕緣電阻(zǔ)下降，從而(ér)導致井(jǐng)下設備，電纜經(jīng)常發(fā)生(shēng)絕(jué)緣(yuán)強度(dù)降低，單(dān)相(xiāng)漏電或單相(xiāng)接地故(gù)障(zhàng)，不(bù)及時處理(lǐ)就可(kě)能(néng)進(jìn)一步(bù)發(fā)展成相(xiāng)間短(duǎn)路。因(yīn)此，井下(xià)作(zuò)業(yè)人(rén)員(yuán)比(bǐ)正(zhèng)常(cháng)環境下(xià)更容易遭受(shòu)電擊的(dí)危險，而且(qiě)還可(kě)能導致(zhì)瓦斯(sī)，煤(méi)塵的爆(bào)炸(zhà)。

     顯(xiǎn)而易(yì)見，對(duì)礦山井(jǐng)下IT係(xì)統的實時(shí)絕緣監測(cè)具有更重(zhòng)要的(dí)意義。

     As we all know, energy is an important engine of economic development and it is also the lifeblood of the national economy. The mining industry has always been the important pillar of the energy industry. China’s mining production mainly comes from underground where the environment is harsh.For example, there are five natural disasters: water, fire, gas, coal dust, and coal seam roof. In addition, the production environment is complex and it’s easy to cause the fatal accidents.

     For safety reasons, the low-voltage power distribution system in the mine adopts an IT system. It is a system that neutral is ungrounded and conductive part of the load is directly grounded (PE line). The features of the IT system is that when the first grounding fault occurs, the current of grounding fault is very small, the voltage of exposed conductive part to ground is below 50V, It is unnecessary to cut off the fault circuit immediately, so it can ensure the continuity of power supply. But at this time, the voltage of non-fault relative to ground will increase by 1.732 times, and the requirement for line withstand voltage will increase. At the same time, once a secondary grounding occurs, it will lead to a dangerous phase-to-phase short-circuit, so an insulation monitoring device should be installed which can help eliminate hidden dangers in time when the first grounding occurs.For the coal mine as the typical representative of underground environment , in the process of mining, due to limited space, long in depth, humid air, dustiness, waterlogged roadway, and many other adverse factors, it is easy to cause the cable insulation resistance and electric equipment aging and decline, the underground equipment and cables often suffer from insulation strength reduction, single-phase leakage or single-phase grounding fault, If not handled in time, it may further develop into phase to phase short circuit. As a result, Underground workers are more vulnerable to electric shock than they would be in a regular environment, and may also cause explosion of gas and coal dust.

     Obviously, It has more important significance for the real-time insulation monitoring of mine IT system.

2 .國內(nèi)外絕緣(yuán)監測儀(yí)在綫監(jiān)測(cè)現狀

     Online monitoring status of insulation monitors at home and abroad

     我國的(dí)電(diàn)氣(qì)設(shè)計在(zài)建(jiàn)國(guó)之初(chū)師從(cóng)前(qián)蘇聯電(diàn)氣規範(fàn)，主要是(shì)廣(guǎng)泛(fàn)的采(cǎi)用TN—C係統，它(tā)可以節省一(yī)根PE綫(xiàn)，比較(jiào)經濟，但(dàn)存(cún)在很多(duō)缺(quē)點，如(rú)中(zhōng)性綫(xiàn)斷(duàn)裂(liè)後設備外殼(ké)對地將(jiāng)帶220V危(wēi)險接觸電壓，不能(néng)裝用(yòng)RCD防電(diàn)擊等等(děng)。改革開放之後(hòu)我(wǒ)國引進了國際(jì)電(diàn)工學會標(biāo)準，也隨(suí)著(zhuó)我(wǒ)國(guó)電(diàn)氣(qì)技術的不斷(duàn)提(tí)高(gāo)，在應用中TN-S，TT，IT係統得到了(liǎo)一定(dìng)程(chéng)度(dù)的推(tuī)廣和(hé)應用(yòng)，以(yǐ)IT係統(tǒng)為(wéi)例，在醫療IT方(fāng)麵(miàn)目(mù)前(qián)應用(yòng)比較成(chéng)熟(shú)，但(dàn)在(zài)很(hěn)多工業場合，由(yóu)於對(duì)接地(dì)係(xì)統的理解和應(yīng)用(yòng)尚不(bù)盡深入和全(quán)方麵，比如煤礦(kuàng)井下(xià)場(cháng)合比(bǐ)較缺(quē)乏國(guó)產絕緣監測裝(zhuāng)置就(jiù)是一個證明(míng)。目前礦用井下IT係統(tǒng)的(dí)絕緣(yuán)監測裝置以(yǐ)進口品牌為主，歐美(měi)等發(fā)達(dá)國家已經(jīng)較廣泛地在IT配電(diàn)網絡(luò)中(zhōng)應(yīng)用絕緣檢測技術，而且經過長(cháng)期的在(zài)綫運行使發(fā)達國家(jiā)積累了大量監(jiān)測(cè)數(shù)據和經驗，這是目(mù)前國(guó)內生產廠(chǎng)家需(xū)要學習(xí)和追趕(gǎn)的(dí)。

     但采用進(jìn)口品牌(pái)絕緣監測(cè)裝置(zhì)造(zào)價昂貴(guì)，而且人(rén)機界(jiè)麵往(wǎng)往(wǎng)是(shì)英文，不利於現(xiàn)場人員的使用(yòng)，在這(zhè)種背(bèi)景(jǐng)下，也(yě)不(bù)斷有國內企(qǐ)業逐步(bù)推出了自己(jǐ)的(dí)工(gōng)業(yè)用(yòng)絕(jué)緣監(jiān)測裝(zhuāng)置(zhì)，其中就包括了安科瑞(ruì)電氣(qì)有(yǒu)限(xiàn)公司的(dí)AIM-T係(xì)列絕緣監(jiān)測儀(yí)。

     At the beginning of the founding of the People's Republic of China, China's electrical design was based on the former Soviet Union's electrical code, mainly using TN-C system . It can save a PE line, which is more economical, but there are many disadvantages, such as, after the neutral line breaks, the equipment shell to the ground will have a dangerous contact voltage of 220 V, and RCD cannot be installed to prevent electric shock, etc. After the reform and opening up, China has introduced the standards of IEC, and with the continuous improvement of electrical technology in China, TN-S, TT and IT systems have been promoted and applied to a certain extent. For example, the application in medical IT is relatively mature at present, but in many industrial occasions, due to the understanding and application of grounding system is not thorough and comprehensive, for example, the lack of domestic insulation monitoring device in coal mine is a proof.At present, the insulation monitoring devices of mine underground IT system are mainly imported brands.Insulation detection technology have been widely used in IT distribution network in developed countries such as Europe and the United States. And they have accumulated a lot of monitoring data and experience after a long-term online operation. This is what domestic manufacturers need to learn and catch up with.

    However, it is expensive to use imported brand insulation monitoring devices, and the human-computer interface is often in English, which is not conducive to the use of field workers. There are also domestic enterprises which have gradually launched their own industrial insulation monitoring devices, including the AIM-T series insulation monitoring devices of Acrel.

3 安科瑞工業(yè)絕緣監測儀(yí)

Acrel industrial insulation monitor

AIM-T300

AIM-T500

AIM-T500L

     AIM-T係列絕(jué)緣監測(cè)儀主要(yào)應(yīng)用(yòng)在(zài)工業(yè)場(cháng)所(suǒ)IT配電係統(tǒng)中，主要(yào)包(bāo)括AIM-T300，AIM-T500和(hé)AIMT500L三款產品(pǐn)，均(jūn)適(shì)用於純(chún)交(jiāo)流，純(chún)直流以及交(jiāo)直流(liú)混合的係(xì)統(tǒng)。

     其(qí)中(zhōng)AIM-T300適用於(yú)450V以下的交流，直流(liú)以及(jí)交直流混合係統(tǒng)，AIM-T500適用(yòng)於800V以(yǐ)下的交(jiāo)流，直(zhí)流以及交(jiāo)直(zhí)流(liú)混合係(xì)。AIM-T500L則(zé)是相(xiāng)比AIM-T500增(zēng)加(jiā)了絕(jué)緣故障定(dìng)位功能。

     AIM-T series insulation monitor is mainly used in IT power distribution system of industrial site, including AIM-T300, AIM-T500 and AIM-T500L, which are all applicable to pure AC, pure DC and AC / DC hybrid systems.

     AIM-T300 is suitable for AC, DC and AC / DC hybrid systems below 450V, and AIM-T500 is suitable for AC, DC and AC / DC hybrid systems below 800V. AIM-T500L has the function of insulation fault location compared with AIM-T500.

1）AIM –T係列(liè)產品的技術參(cān)數如(rú)下表(biǎo)所示：

The technical parameters of AIM-T series products are shown in the table below

2）AIM –T係(xì)列產品(pǐn)的典型應用(yòng)如(rú)下(xià)圖所示：

The typical application of aim-t series products is shown in the following figure:

4 小(xiǎo)結Summary

     安(ān)科(kē)瑞AIM-T係列工(gōng)業(yè)用(yòng)絕緣監(jiān)測儀(yí)目(mù)前已(yǐ)經在(zài)礦(kuàng)井(jǐng)，紙(zhǐ)業(yè)，船(chuán)舶，冶(yě)金廠等的(dí)諸(zhū)多(duō)工(gōng)業場合的IT係統中(zhōng)得到了(liǎo)應用(yòng)，能(néng)夠(gòu)實(shí)時監測係(xì)統對(duì)地的絕緣(yuán)狀況(kuàng)，在(zài)係(xì)統出(chū)現絕緣(yuán)下(xià)降(jiàng)或接地故障時，及(jí)時(shí)報(bào)警(jǐng)提醒(xǐng)相(xiāng)關人員排查(chá)故障，在應用中(zhōng)起到(dào)了很好的(dí)監控(kòng)和預防效果(guǒ)。

     At present, Acrel AIM-T series industrial insulation monitor has been applied in the IT system of many industrial occasions, such as mine, paper industry, ship, metallurgy plant, etc. It can monitor the insulation condition of the system to the ground in real time. When the system has insulation drop or ground fault, it can alarm and remind relevant person to check the fault, which has a good monitoring and prevention effect in the application.

參(cān)考(kǎo)文獻(xiàn) Bibliography

1.Solutions for enterprise micro-grid system