摘要:眾所周知,能源作為經(jīng)濟(jì)發(fā)展的重要引擎,堪稱(chēng)是國(guó)民經(jīng)濟(jì)的命脈。采礦業(yè)一直是能源工業(yè)的重要支柱,我國(guó)的礦業(yè)生產(chǎn)主要來(lái)自井下開(kāi)采,環(huán)境惡劣,就以煤礦為例,煤礦井下存在水、火、瓦斯、煤塵、頂板五大自然災(zāi)害,加上生產(chǎn)環(huán)境復(fù)雜,易發(fā)生惡性事故。出于**考慮,礦山井下低壓配電系統(tǒng)按規(guī)定采用的是IT系統(tǒng)。IT系統(tǒng)就是電源中性點(diǎn)不接地、用電設(shè)備外露可導(dǎo)電部分直接接地(PE線)的系統(tǒng)。IT系統(tǒng)的特點(diǎn)是發(fā)生一次接地故障時(shí),接地故障電流僅為非故障相對(duì)地的電容電流,其值很小,外露導(dǎo)電部分對(duì)地電壓不過(guò)50V,不需要立即切斷故障回路,因此可以保證供電的連續(xù)性。但此時(shí)非故障相對(duì)地電壓會(huì)升高1.732倍,對(duì)線路耐壓要求提升;同時(shí)一旦發(fā)生二次接地,則構(gòu)成危險(xiǎn)的相間短路,所以須配置絕緣監(jiān)測(cè)裝置,以便在發(fā)生一次接地時(shí)就要及時(shí)排除隱患。而對(duì)于以煤礦為典型代表的井下環(huán)境來(lái)說(shuō),在開(kāi)采過(guò)程中,由于工作場(chǎng)所空間小、縱深長(zhǎng),加上空氣潮濕、多塵、巷道滴水和積水等諸多惡劣因素,很容易引起電纜和電氣設(shè)備老化和絕緣電阻下降,從而導(dǎo)致井下設(shè)備、電纜經(jīng)常發(fā)生絕緣強(qiáng)度降低、單相漏電或單相接地故障,不及時(shí)處理就可能進(jìn)一步發(fā)展成相間短路。因此,井下作業(yè)人員比正常環(huán)境下更容易遭受電擊的危險(xiǎn),而且還可能導(dǎo)致瓦斯、煤塵的爆炸。
顯而易見(jiàn),對(duì)礦山井下IT系統(tǒng)的實(shí)時(shí)絕緣監(jiān)測(cè)具有更重要的意義。
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(guó)內(nèi)外絕緣監(jiān)測(cè)儀在線監(jiān)測(cè)現(xiàn)狀
Online monitoring status of insulation monitors at home and abroad
我國(guó)的電氣設(shè)計(jì)在建國(guó)之初師從前蘇聯(lián)電氣規(guī)范,主要是廣泛的采用TN—C系統(tǒng),它可以節(jié)省一根PE線,比較經(jīng)濟(jì),但存在很多缺點(diǎn),如中性線斷裂后設(shè)備外殼對(duì)地將帶220V危險(xiǎn)接觸電壓,不能裝用RCD防電擊等等。改革開(kāi)放之后我國(guó)引進(jìn)了國(guó)際電工學(xué)會(huì)標(biāo)準(zhǔn),也隨著我國(guó)電氣技術(shù)的不斷提高,在應(yīng)用中TN-S、TT、IT系統(tǒng)得到了一定程度的推廣和應(yīng)用,以IT系統(tǒng)為例,在醫(yī)療IT方面目前應(yīng)用比較成熟,但在很多工業(yè)場(chǎng)合,由于對(duì)接地系統(tǒng)的理解和應(yīng)用尚不盡深入,比如煤礦井下場(chǎng)合比較缺乏國(guó)產(chǎn)絕緣監(jiān)測(cè)裝置就是一個(gè)證明。目前礦用井下IT系統(tǒng)的絕緣監(jiān)測(cè)裝置以進(jìn)口為主,歐美等發(fā)達(dá)國(guó)家已經(jīng)較廣泛地在IT配電網(wǎng)絡(luò)中應(yīng)用絕緣檢測(cè)技術(shù),而且經(jīng)過(guò)長(zhǎng)期的在線運(yùn)行使發(fā)達(dá)國(guó)家積累了大量監(jiān)測(cè)數(shù)據(jù)和經(jīng)驗(yàn),這是目前國(guó)內(nèi)生產(chǎn)廠家需要學(xué)習(xí)和追趕的。
但采用進(jìn)口絕緣監(jiān)測(cè)裝置造價(jià)昂貴,而且人機(jī)界面往往是英文,不利于現(xiàn)場(chǎng)人員的使用,在這種背景下,也不斷有國(guó)內(nèi)企業(yè)逐步推出了自己的工業(yè)用絕緣監(jiān)測(cè)裝置,其中就包括了安科瑞電氣有限公司的AIM-T系列絕緣監(jiān)測(cè)儀。
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(jiān)測(cè)儀
Acrel industrial insulation monitor
AIM-T300

AIM-T500
AIM-T500L
AIM-T系列絕緣監(jiān)測(cè)儀主要應(yīng)用在工業(yè)場(chǎng)所IT配電系統(tǒng)中,主要包括AIM-T300、AIM-T500和AIMT500L三款產(chǎn)品,均適用于純交流、純直流以及交直流混合的系統(tǒng)。
其中AIM-T300適用于450V以下的交流、直流以及交直流混合系統(tǒng),AIM-T500適用于800V以下的交流、直流以及交直流混合系。AIM-T500L則是相比AIM-T500增加了絕緣故障定位功能。
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.
小結(jié)Summary
安科瑞AIM-T系列工業(yè)用絕緣監(jiān)測(cè)儀目前已經(jīng)在礦井、紙業(yè)、船舶、冶金廠等的諸多工業(yè)場(chǎng)合的IT系統(tǒng)中得到了應(yīng)用,能夠?qū)崟r(shí)監(jiān)測(cè)系統(tǒng)對(duì)地的絕緣狀況,在系統(tǒng)出現(xiàn)絕緣下降或接地故障時(shí),及時(shí)報(bào)警提醒相關(guān)人員排查故障,在應(yīng)用中起到了很好的監(jiān)控和預(yù)防效果。
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.