機(jī)械制造廠(chǎng)總降變電所設(shè)計(jì)外文翻譯

1、<p><b>　　畢業(yè)設(shè)計(jì)外文翻譯</b></p><p>　　機(jī)械制造廠(chǎng)總降變電所設(shè)計(jì)</p><p>　　Machinery manufacturing factory total step-down substation design</p><p>　　學(xué)生學(xué)號(hào)： </p>

2、<p>　　學(xué)生姓名： </p><p>　　專(zhuān)業(yè)班級(jí)： </p><p>　　指導(dǎo)教師： </p><p>　　職 稱(chēng)： </p><p>　　起止日期：

3、 </p><p>　　一種實(shí)用的輸配電系統(tǒng)的維護(hù)優(yōu)化計(jì)劃</p><p>　　Sohrab Asgarpoor Mohamad Doghman </p><p>　　Department of Electrical Engineering Principal Research Engineer </p><p>　　Un

4、iversity of Nebraska-Lincoln Omaha Public Power Distric</p><p><b>　　摘要：</b></p><p>　　今天，維護(hù)和提高系統(tǒng)的可靠性和降低運(yùn)營(yíng)和維護(hù)成本是電力的首要任務(wù)。由于系統(tǒng)設(shè)備繼續(xù)老化，并逐漸惡化，由于組件故障增加的服務(wù)中斷的概率。一個(gè)有效的維護(hù)策略是在提供安全可靠的電力客戶(hù)經(jīng)濟(jì)所必需的。本

5、文的目的是提供一個(gè)預(yù)測(cè)，條件為基礎(chǔ)的框架，且成本有效的維護(hù)，輸電和配電系統(tǒng)的優(yōu)化方案。</p><p><b>　　引言:</b></p><p>　　原則上，提高系統(tǒng)的可靠性和降低運(yùn)營(yíng)和維護(hù)成本是電力的重中之重。在競(jìng)爭(zhēng)日益激烈的電力輸送環(huán)境，電力公司被迫申請(qǐng)實(shí)用資產(chǎn)管理更加積極主動(dòng)的方法。的電力交貨資產(chǎn)管理的主要組成部分之一，是資本預(yù)算和現(xiàn)有設(shè)施。由于在許多情況下，

6、建設(shè)和設(shè)備采購(gòu)的成本是固定的，支出為削減成本和潛在的儲(chǔ)蓄的主要候選人。由于系統(tǒng)設(shè)備繼續(xù)老化，并逐漸惡化，由于組件故障增加的服務(wù)中斷的概率。</p><p>　　電力公司都面臨著許多挑戰(zhàn)，在這種競(jìng)爭(zhēng)的新時(shí)代：上升成本，系統(tǒng)上的需求不斷增長(zhǎng)，保持高可靠性和電能質(zhì)量水平和管理設(shè)備老化。</p><p>　　因此，健康的設(shè)備是由設(shè)備條件的影響，因?yàn)槭杖胄袠I(yè)至關(guān)重要。當(dāng)需求高和設(shè)備的工作秩序，豐厚的

7、收入可以實(shí)現(xiàn)的。相反，不健康的設(shè)備可能會(huì)導(dǎo)致服務(wù)中斷，顧客不滿(mǎn)，善意的損失，并最終失去客戶(hù)。提供安全可靠的電力客戶(hù)經(jīng)濟(jì)有效的維護(hù)策略是必不可少的。</p><p>　　前二戰(zhàn)時(shí)期期間，產(chǎn)業(yè)是不是非常高度機(jī)械化，因此停機(jī)時(shí)間的影響并不十分顯著。此外，設(shè)備簡(jiǎn)單容易解決，公司的表現(xiàn)主要是糾正性維護(hù)（CM）。郵政第二次世界大戰(zhàn)期間，直到20世紀(jì)70年代中期的時(shí)代，提高機(jī)械化導(dǎo)致更紛繁復(fù)雜的設(shè)備。公司已開(kāi)始大量依靠此設(shè)備。

8、這種依賴(lài)導(dǎo)致的預(yù)防性維護(hù)（PM）的概念。下午，在1960年，主要包括在固定的時(shí)間間隔進(jìn)行設(shè)備大修。此外，這臺(tái)設(shè)備的成本增加，導(dǎo)致管理開(kāi)始尋找方法來(lái)提高這些資產(chǎn)的生命。</p><p>　　最新的時(shí)代開(kāi)始了與中航工業(yè)在早期到1970年代中期。在想，以確保設(shè)備持續(xù)盡可能長(zhǎng)的正確和經(jīng)營(yíng)的企業(yè)造成新的高度機(jī)械化設(shè)備的巨額費(fèi)用。這個(gè)時(shí)代，也標(biāo)志著在提高安全意識(shí)（尤其是在航空業(yè)）和環(huán)境后果。越來(lái)越多，發(fā)生故障的安全或環(huán)境的危

9、害。所有這一切導(dǎo)致的維修費(fèi)用的增加。在某些行業(yè)，維護(hù)成本代表的第二個(gè)最高甚至經(jīng)營(yíng)成本最高的組件。</p><p><b>　　1.1維護(hù)策略</b></p><p>　　在一般情況下，維護(hù)計(jì)劃或無(wú)計(jì)劃.</p><p>　　糾正性維修是一種被動(dòng)的戰(zhàn)略，這是無(wú)計(jì)劃和故障發(fā)生后，正在開(kāi)展。我們的目的是恢復(fù)一個(gè)項(xiàng)目到一個(gè)國(guó)家能夠履行其所需的功能。計(jì)劃

10、中的維護(hù)策略在本質(zhì)上是積極的，可分為兩組：預(yù)防和狀態(tài)監(jiān)測(cè)。有時(shí)也被稱(chēng)為預(yù)定的預(yù)防性維護(hù)，定期進(jìn)行維護(hù)。這個(gè)類(lèi)別下，可以選擇有四個(gè)基本任務(wù)：</p><p>　　a) 時(shí)間導(dǎo)演的任務(wù)涉及到的操作數(shù)，工作時(shí)間，或季節(jié)性變化。</p><p>　　b）未能發(fā)現(xiàn)是用于識(shí)別設(shè)備故障不屬于明顯的經(jīng)營(yíng)人員（隱性故障）。通常用于保護(hù)設(shè)備。</p><p>　　c）條件導(dǎo)演適用的情況

11、時(shí)，設(shè)備條件達(dá)到了一個(gè)極限，或者續(xù)令人滿(mǎn)意操作時(shí)不能保證。它可以防止早期失效，成為真正的失敗。</p><p>　　d）運(yùn)行故障是一個(gè)選擇的選項(xiàng)，只有在不能確定的事件，技術(shù)上是正確的，符合成本效益的任務(wù)。</p><p>　　當(dāng)它認(rèn)為有必要的基礎(chǔ)上定期檢查，診斷測(cè)試或其他狀態(tài)監(jiān)測(cè)手段，進(jìn)行了預(yù)測(cè)性維修（PDM）。狀態(tài)監(jiān)測(cè)是用來(lái)預(yù)測(cè)設(shè)備故障監(jiān)測(cè)或診斷活動(dòng)。</p><p&

12、gt;　　1.2以可靠性為中心的維修（RCM）</p><p>　　在20世紀(jì)60年代末，中航工業(yè)在生產(chǎn)第一“的大型噴氣式客機(jī)”的邊緣。新747的三倍大小ofany目前在空氣中的其他客機(jī)。 747，新的發(fā)動(dòng)機(jī)，其結(jié)構(gòu)，航空電子設(shè)備，并像所有聯(lián)邦航空管理局（FAA）??最初采取的立場(chǎng)，即747預(yù)防性維護(hù)將是非常廣泛的，很多技術(shù)進(jìn)步公認(rèn)的大小 - 如此廣泛，事實(shí)上，航空公司不可能在一個(gè)有利可圖的方式經(jīng)營(yíng)這架飛機(jī)。這個(gè)

13、問(wèn)題導(dǎo)致飛機(jī)制造業(yè)完全重新評(píng)估它的PM計(jì)劃。是什么導(dǎo)致這方面的努力是一種全新的方式，聘請(qǐng)排名PM任務(wù)，必要時(shí)要保留的關(guān)鍵飛機(jī)飛行功能決定樹(shù)的過(guò)程。這項(xiàng)新技術(shù)，最終由美國(guó)聯(lián)邦航空局的批準(zhǔn)，不久發(fā)展到什么是已知的可靠性為中心的維修（RCM）的。德盛導(dǎo)致主要?jiǎng)趧?dòng)力，原材料成本和庫(kù)存成本降低航空業(yè)使用。此外，它適用于在1980年的核電產(chǎn)業(yè)。今天，RCM是許多行業(yè)，包括電力行業(yè)選擇的維修技術(shù)。</p><p>　　優(yōu)點(diǎn)是能

14、夠與制造商合作，創(chuàng)建一個(gè)為新一代設(shè)備的RCM方案不同的是航空業(yè)，公用事業(yè)行業(yè)，尤其是發(fā)電行業(yè)，已采取作為一個(gè)歷史悠久的修改德盛現(xiàn)有電廠(chǎng)的維修方法。盡管在“中游”德盛計(jì)劃的實(shí)施有關(guān)的費(fèi)用，他們已經(jīng)發(fā)現(xiàn)自己在很短的時(shí)間內(nèi)支付。</p><p>　　RCM，已被主要應(yīng)用于核電廠(chǎng)，往往需要最大的維修量，因?yàn)榘踩铜h(huán)境方面的考慮。然而，這些成功的方案現(xiàn)在經(jīng)營(yíng)，化石發(fā)電廠(chǎng)和輸電和配電系統(tǒng)，最近已進(jìn)入混合。因?yàn)檫@些設(shè)施都面臨著

15、一個(gè)不太嚴(yán)格的監(jiān)管環(huán)境，他們應(yīng)該能夠直接適用簡(jiǎn)化RCM的形式更容易，從而降低了實(shí)施成本。</p><p>　　改造維修方案的第一步是要落實(shí)在RCM的方法whichwill幫助建立一個(gè)新的方案的優(yōu)先次序。具體來(lái)說(shuō)，RCM是一套旨在幫助一個(gè)實(shí)用程序來(lái)確定一套最低限度的預(yù)防性維修任務(wù)，要妥善處理關(guān)鍵設(shè)備故障不影響服務(wù)的可靠性的方法和工具。 RCM是一種結(jié)構(gòu)化的過(guò)程，在一個(gè)特定的經(jīng)營(yíng)環(huán)境，以確定最佳的設(shè)備維護(hù)要求。它結(jié)合

16、了糾正性維護(hù)，預(yù)防性維護(hù)和預(yù)測(cè)性維護(hù)策略，并適用于這些策略是適當(dāng)?shù)模渲忻總€(gè)功能失敗的后果和頻率的基礎(chǔ)上。這種結(jié)合產(chǎn)生的維修計(jì)劃，優(yōu)化可靠性和成本效益。對(duì)于重大件設(shè)備，電力變壓器，如RCM可能表明，預(yù)測(cè)性維修是一個(gè)有吸引力的選擇，傳感器和診斷技術(shù)和運(yùn)行設(shè)備故障增加了成本的降低成本。</p><p>　　RCM是一個(gè)基于條件的維護(hù)計(jì)劃，重點(diǎn)是防止有可能是最嚴(yán)重的失敗。 RCM和預(yù)測(cè)維修（PDM）的分析相得益彰，當(dāng)它

17、們同時(shí)執(zhí)行，維護(hù)優(yōu)化提供了一個(gè)極好的方法。在過(guò)去的幾年中，監(jiān)測(cè)設(shè)備市場(chǎng)上的成熟，電子和計(jì)算機(jī)的價(jià)格下降了現(xiàn)場(chǎng)監(jiān)測(cè)應(yīng)用具有成本效益的現(xiàn)實(shí)。</p><p>　　可以很容易解釋的基本概念和基本原則的RCM。其主要方法可以歸結(jié)為以下四點(diǎn)：</p><p>　　1）保護(hù)系統(tǒng)功能2）確定主要失效模式3）優(yōu)先功能的需求，使預(yù)算可以集中保存最關(guān)鍵的功能4）選擇只適用和有效的維護(hù)任務(wù)RCM的一些好

18、處是：1）減少主要整改措施2）消除不必要的大修和日常工作提供一點(diǎn)好處3）優(yōu)化的頻率所需的大修4）提高預(yù)測(cè)技術(shù)的使用，幫助與資源規(guī)劃5）減少使用侵入性的任務(wù)，可誘發(fā)設(shè)備故障6）提高日常工作的成本效益7）創(chuàng)建記錄的維修方案的技術(shù)基礎(chǔ)8）允許納入現(xiàn)有的維護(hù)，已被證明是具有成本效益的做法，容易實(shí)施9）過(guò)程的知識(shí)，通信和團(tuán)隊(duì)精神</p><p>　　正在開(kāi)發(fā)廉價(jià)的固態(tài)傳感器，例如，可以插在變壓器油檢測(cè)的保

19、溫開(kāi)始惡化時(shí)，產(chǎn)生的氣體的存在。一旦信息變得可預(yù)測(cè)性維護(hù)技術(shù)，它需要與來(lái)自全國(guó)各地電力網(wǎng)絡(luò)，并從歷史記錄上線(xiàn)的數(shù)據(jù)集成。</p><p><b>　　1.3新技術(shù)</b></p><p>　　有許多技術(shù)可用的今天，一些新的方法正在調(diào)查，以確定設(shè)備狀態(tài)。以下僅僅是用于監(jiān)測(cè)電力傳輸設(shè)備的幾個(gè)應(yīng)用程序：</p><p><b>　?。?超聲

20、波噪聲分析</b></p><p><b>　?。?局部放電檢測(cè)</b></p><p>　　該技術(shù)采用電傳感器檢測(cè)絕緣子和終止，如電氣設(shè)備的初始絕緣擊穿。局部放電檢測(cè)是用來(lái)檢測(cè)重大損害發(fā)生前的早期故障。</p><p>　?。?變壓器油天然氣分析</p><p>　　這是必要的，以保持變壓器上線(xiàn)盡可能。異常

21、的指標(biāo)之一是在變壓器油中溶解氣體的含量。某些氣體含量可以表明老化，需要維修，或潛在的故障。</p><p><b>　?。?紅外熱成像</b></p><p>　　熱調(diào)查涉及紅外攝像機(jī)的使用在電廠(chǎng)使用的大型電機(jī)檢測(cè)熱點(diǎn)。</p><p><b>　?。?聲音強(qiáng)度測(cè)量</b></p><p>　　聲強(qiáng)

22、計(jì)需要找出潛在的問(wèn)題，在設(shè)備和錄制的聲音和輸出設(shè)備的歷史變遷 對(duì)于輸電和配電系統(tǒng)，如變壓器故障氣體分析儀的傳感器可能被證明是有益的。此設(shè)備提供實(shí)時(shí)測(cè)量變壓器故障電流的四個(gè)關(guān)鍵氣體：一氧化碳，氫氣，乙炔和乙烯。下一步是把一個(gè)額外的傳感器檢測(cè)水分的存在，從而可降低介電強(qiáng)度和導(dǎo)致失敗。這將被用來(lái)測(cè)量變壓器負(fù)載，使負(fù)載的功能特點(diǎn)，演化的關(guān)鍵氣體和水分可以作為與其他設(shè)備。隨著濕度傳感器和負(fù)載電流監(jiān)視器，我們可以開(kāi)發(fā)加載壓力條件下的變壓器，

23、而不是依靠現(xiàn)在提供了過(guò)于保守的評(píng)級(jí)準(zhǔn)確的標(biāo)準(zhǔn)。</p><p>　　1.4擬議的綜合方法</p><p>　　輸電和配電系統(tǒng)的集成方法，將確保導(dǎo)致為一個(gè)特定的負(fù)載設(shè)備或子系統(tǒng)，在各部門(mén)的維修水平將得到統(tǒng)一和一致，從而提升和優(yōu)化維修過(guò)程。 為了建立一個(gè)維修方案，RCM過(guò)程大概需要是驅(qū)動(dòng)點(diǎn)。顯示為維護(hù)優(yōu)化方案需要不同的策略。經(jīng)典的RCM過(guò)程包括識(shí)別系統(tǒng)進(jìn)行研究，他們的功能，功能故障，故

24、障模式，故障原因，維修任務(wù)選擇。</p><p>　　需要確定設(shè)備最關(guān)鍵部分，從而影響系統(tǒng)的整體功能。換句話(huà)說(shuō)，我們需要識(shí)別設(shè)備時(shí)失敗的嚴(yán)重后果。此外，關(guān)鍵客戶(hù)和領(lǐng)先的負(fù)載設(shè)備需要確定。影響這些客戶(hù)的所有設(shè)備都需要進(jìn)行分析，并應(yīng)確定設(shè)備的最關(guān)鍵部分。我們還需要了解客戶(hù)在可靠性，安全性，電能質(zhì)量，成本等方面的需要，這些屬性必須加權(quán)，以確定最佳的維護(hù)策略與這些客戶(hù)打交道。 為了優(yōu)化公用事業(yè)維修計(jì)劃，所有相關(guān)信

25、息，必須使用最有效的啟動(dòng)，計(jì)劃，跟蹤，記錄，分析維護(hù)任務(wù)。一個(gè)開(kāi)放的通訊協(xié)議，使各種監(jiān)控設(shè)備（不管制造商）與utilityoffices，互相交談，并與控制中心，最適合電力的需求，通過(guò)整合各種數(shù)據(jù)源和其他軟件模塊。 目前，許多大型公用事業(yè)機(jī)構(gòu)執(zhí)行一些診斷測(cè)試設(shè)備。許多電腦他們的維修工作，包括保留維護(hù)的歷史，記錄重要的業(yè)務(wù)活動(dòng)，維護(hù)設(shè)備的設(shè)計(jì)資料庫(kù)管理功能。適當(dāng)?shù)臏贤?，整合和分析所有這些信息將導(dǎo)致更準(zhǔn)確的建議，關(guān)于何時(shí)執(zhí)行維護(hù)和特

26、定的設(shè)備如何操作。 在同行業(yè)中的一個(gè)典型的問(wèn)題是，在次，收集大量的數(shù)據(jù)，但它沒(méi)有集成和處理方便快速評(píng)估。無(wú)法在此結(jié)果使直接Mrecommendations的，而未能提供成本效益可能已經(jīng)實(shí)現(xiàn)，</p><p>　　結(jié)論: 今天，降低運(yùn)營(yíng)和維護(hù)成本和維護(hù)服務(wù)的可靠性，實(shí)用輸電和配電系統(tǒng)的管理者的首要任務(wù)。 RCM的概念是健全的，應(yīng)提供一個(gè)結(jié)構(gòu)化的方法與維修維護(hù)和可靠性改進(jìn)的成本之間的最佳平衡方案的事業(yè)

27、。 RCM和PDM分析相得益彰，并同時(shí)進(jìn)行時(shí)，提供一個(gè)很好的方法來(lái)維護(hù)的優(yōu)化。</p><p><b>　　參考文獻(xiàn)</b></p><p>　　[1] G. J. Anders, Probability Concepts in Electric Power Systems, 1990, John Wiley & Sons. </p><p

28、>　　[2] J. Moubray, Reliability-Centered Maintenance, Industrial Press Inc., 1992. </p><p>　　[3] A. M. Smith, Reliability-Centered Maintenance, McGraw-Hill Book Co., 1993. </p><p>　　[4] S. Asg

29、arpoor and C. Singh, “Methods for Detection of Equipment Aging and Incorporating it in the Reliability Analysis”, Proceedings of NSF Symposium on Electric Power Systems Infrastructure, Pullman, WA, October 1994. </p&g

30、t;<p>　　[5] J. Douglas, “The Maintenance Revolution”, EPRI Journal, Vol. 20, No. 3, May/June 1995, pp. 6-15.</p><p>　　A Maintenance Optimization Program for Utilities’ Transmission and Distribution Sy

31、stems</p><p>　　Sohrab Asgarpoor Mohamad Doghman </p><p>　　Department of Electrical Engineering Principal Research Engineer </p><p>　　University of Nebraska-Lincoln Omaha Public Powe

32、r Distric</p><p>　　ABSTRACT: Today, preserving and/or enhancing system reliability and reducing operations and maintenance (O&M) costs are top priorities for electric utilities. As system equipment conti

33、nue to age and gradually deteriorate, the probability of service interruption due to component failure increases. An effective maintenance strategy is essential in delivering safe and reliable electric power to customers

34、 economically. The objective of this paper is to provide a framework for a predictive, condition</p><p>　　1. INTRODUCTION </p><p>　　In principle, improving system reliability and reducing Operat

35、ions and Maintenance (O&M) costs are top priorities of electric utilities. In an increasingly competitive power delivery environment, electric utilities are forced to apply more proactive methods of utility asset man

36、agement. One of the main components of electric power delivery asset management is the capital budgeting and O&M of existing facilities. Since in many cases the cost of construction and equipment purchases are fixed,

37、 O&M e</p><p>　　Electric utilities are confronted with many challenges in this new era of competition: rising O&M costs, growing demand on systems, maintaining high levels of reliability and power qu

38、ality, and managing equipment aging.</p><p>　　Therefore, the health of equipment is of utmost importance to the industry because revenues are affected by the condition of equipment. When demand is high and e

39、quipment is in working order, substantial revenues can be realized. On the contrary, unhealthy equipment can result in service interruption, customer dissatisfaction, loss of good will, and eventual loss of customers. An

40、 effective maintenance strategy is essential to delivering safe and reliable electric power to customers economically.</p><p>　　2.MAINTENANCE </p><p>　　During the Pre-World War II era, industry

41、was not very highly mechanized, therefore the impact of down time was not very significant [2]. Also, equipment was simpler which made it easy to fix, and companies performed mainly Corrective Maintenance (CM). During th

42、e Post-World War II until the mid 1970’s era, increased mechanization led to more numerous and complex equipment. Companies were beginning to rely heavily on this equipment. This dependence led to the concept of Preventi

43、ve Maintenance (PM</p><p>　　The latest era began with the aircraft industry in the early to mid 1970’s. The huge costs of new highly-mechanized equipment resulted in companies wanting to ensure that equipmen

44、t lasted and operated correctly for as long as possible. This era also marked an increased awareness in safety (especially in the airline industry) and environmental consequences. Increasingly, occurrence of failures rep

45、resent safety or environmental hazards. All of this has led to an increase in the cost of maintenance</p><p>　　3.MAINTENANCE STRATEGIES </p><p>　　In general, maintenance is either planned or unp

46、lanned as shown in Figure 1.</p><p>　　Corrective maintenance is a reactive strategy which is unplanned and is carried out after failure has occurred. The intention is to restore an item to a state that can p

47、erform its required function. Planned maintenance strategies are proactive in nature and can be divided into two groups: Preventive and Condition Monitoring. Preventive maintenance which is sometimes called scheduled, is

48、 a maintenance carried out at regular intervals. There are four basic tasks that can be selected under this cat</p><p>　　Time Directed task involves number of operations, operating hours, or seasonal change.

49、</p><p>　　Failure Finding is for identifying equipment failure that are not evident to the operating crew (hidden failures). Usually used for protective equipment.</p><p>　　Condition Directed ap

50、plies to the situation when the condition of equipment reaches a limit, or when continued satisfactory operation can not be ensured. It prevents incipient failure from becoming real failure. </p><p>　　Run To

51、 Failure is an option that is selected only in the event that a technically correct and cost-effective task can not be identified.</p><p>　　Predictive Maintenance (PdM) is carried out when it is deemed neces

52、sary, based on periodic inspections, diagnostic tests or other means of condition monitoring. Condition Monitoring is the monitoring or diagnostic activity that is used to predict equipment failure. </p><p>

53、;　　4.RELIABILITY CENTERED MAINTENANCE (RCM)</p><p>　　During the late 1960’s, the aircraft industry was on the verge of manufacturing the first “jumbo jets”. The new 747’s were three times the size ofany othe

54、r passenger jets currently in the air. The recognized size of the 747, its new engines, and its many technology advances in structures, avionics, and the like, all led to Federal Aviation Administration (FAA) to initiall

55、y take the position that preventive maintenance on the 747 would be very extensive – so extensive, in fact, that the airlines </p><p>　　Unlike the airline industry which had the advantage of being able to wo

56、rk with manufacturers to create an RCM program for a new generation of equipment, the utility industry, especially the electric power generation industry, has had to adopt RCM as a modification of long-established mainte

57、nance practices at existing plants [4]. Despite the costs associated with the implementation of these RCM programs in “midstream”, they have been found to pay for themselves in very short order.</p><p>　　RCM

58、, as has been mainly applied to nuclear power plants, often requires the largest amount of maintenance because of safety and environmental considerations. However, with these successful programs now operating, fossil pow

59、er plants and power transmission and distribution systems have recently been getting into the mix. Because these facilities face a less restrictive regulatory environment, they should be able to directly apply the stream

60、lines forms of RCM much more easily, thus reducing the im</p><p>　　The first step in revamping a maintenance program is to implement an RCM approach whichwill help establish priorities for a new program. Spe

61、cifically, RCM is a set of methods and tools aimed at helping a utility to determine the minimum set of preventive maintenance tasks necessary to appropriately address critical equipment failures without compromising ser

62、vice reliability. RCM is a structured process used to determine optimal maintenance requirements for equipment in a particular operating env</p><p>　　RCM is a condition-based maintenance program that focuses

63、 on preventing failures that are likely to be the most serious. RCM and Predictive Maintenance (PdM) analyses complement each other, and when they are performed concurrently, offer an excellent approach to maintenance op

64、timization. In the last few years, the sophistication of monitoring equipment on the market and the falling price of electronics and computers have made the on-site monitoring applications a cost effective reality.</p

65、><p>　　The very basic concepts and underlying principles of the RCM can be explained very easily. Its main methodology can be reduced to the following four points:</p><p>　　1) preserve system funct

66、ions </p><p>　　2) identify dominant failure modes </p><p>　　3) prioritize function needs so that budget can be focused on preserving most critical functions </p><p>　　4) select only

67、 applicable and effective maintenance tasks </p><p>　　Some of the benefits of RCM are:</p><p>　　1) Reduces major corrective actions </p><p>　　2) Eliminates unnecessary overhauls and

68、 routine tasks that provide little benefits </p><p>　　3) Optimizes the frequency of required overhauls </p><p>　　4) Increases use of predictive technology that help with resource planning </p

69、><p>　　5) Decreases use of intrusive tasks that can induce equipment failures </p><p>　　6) Improves cost-effectiveness of routine tasks </p><p>　　7) Creates documented technical bases

70、for maintenance programs </p><p>　　8) Allows easy implementation by incorporating existing maintenance practices that have proven to be cost-effective</p><p>　　9) Processes Knowledge, communicat

71、ions, and teamwork </p><p>　　Inexpensive solid state sensors are being developed, for example, that can be inserted in transformer oil to detect the presence of gases produced when insulation begins to deter

72、iorate. Once the information from predictive maintenance technology becomes available, it needs to be integrated with on-line data from across a power network and from historical records.</p><p>　　5.NEW T

73、ECHNOLOGIES </p><p>　　There are many technologies available today, and several new methods are being investigated to determine the equipment condition [5]. The following are just a few applications for monit

74、oring power delivery equipment:</p><p>　　􀂉 Ultrasonic Noise Analysis </p><p>　　The presence of tones in the ultrasonic range can be an indication of leaks of air, gas, steam, and vacuum

75、. Ultrasonic noise can be emitted as a result of friction between moving parts.</p><p>　　􀂉 Partial Discharge Detection </p><p>　　This technology employs an electrical sensor to detect t

76、he initial insulation breakdown in electrical equipment such as insulators and terminators. Partial discharge detection is used to detect incipient failures before significant damage occurs.</p><p>　　⣷

77、13; Transformer Gas-in-Oil Analysis </p><p>　　This is needed to keep the transformer on-line as much as possible. One indicator of abnormalities is the dissolved gas content in the transformer oil. Certain g

78、as levels can indicate aging, the need for maintenance, or potential failure.</p><p>　　􀂉 Infrared Thermography </p><p>　　Thermography surveys involving the use of an infrared camera to

79、detect hot spots in large motors used in power plants.</p><p>　　􀂉 Sound Intensity Measurement </p><p>　　Sound Intensity Meter is needed to identify potential problems in equipment and r

80、ecord the historical changes in sound and output of equipment</p><p>　　For transmission and distribution systems, sensors such as transformer fault gas analyzer might prove to be beneficial. This device prov

81、ides real-time measurement of the four key gases associated with fault currents in transformer: carbon monoxide, hydrogen, acetylene, and ethylene. The next step is to incorporate an additional sensor to detect the prese

82、nce of moisture which can reduce dielectric strength and lead to failure. This will be used with another device that measures the transformer lo</p><p>　　6.PROPOSED INTEGRATED APPROACH </p><p>　

83、　An integrated approach for transmission and distribution systems would ensure that equipment or subsystems leading to serve a particular load would receive uniform and consistent level of maintenance in all departments,

84、 thus enhancing and optimizing the maintenance process.</p><p>　　In order to establish a maintenance program, the RCM process needs to be the driving point. Figure 2. Shows different strategies required for

85、a maintenance optimization program. The classical RCM process involves identifying the systems to be studied, their functions, functional failures, failure modes, failure causes, and the maintenance task selection</p&

86、gt;<p>　　The most critical pieces of equipment which affect the overall function of the system need to be identified. In other words, we need to identify equipment with severe consequences when failed. Also, criti

87、cal customers and the equipment leading to their loads need to be identified. All equipment affecting these customers need to be analyzed, and the most critical pieces of equipment should be determined. We also need to u

88、nderstand the customer needs in terms of reliability, safety, power quality,</p><p>　　In order to optimize the utilities’ maintenance program, all relevant information must be used to most effectively initia

89、te, schedule, track, record, and analyze maintenance tasks. An open communication protocol that enables various monitoring devices (regardless of the manufacturer) to talk to each other, with utilityoffices, and with con

90、trol centers would best suit the needs of electric utilities by integrating various data sources and other software modules.</p><p>　　Currently, many large utility organizations perform some equipment diagno

91、stic tests. Many have computerized their maintenance work management functions including retaining maintenance histories, logging significant operational activities, and maintaining a library of design information for eq

92、uipment. The proper communication, integration and analysis of all of this information would result in more accurate recommendations concerning when to perform maintenance and/or how to operate a specific pi</p>&

93、lt;p>　　A typical problem in the industry is that, at times, a large amount of data is collected but it is not integrated and processed expediently for a quick evaluation. This results in the inability to make immediat

94、e O&Mrecommendations, therebyadding cost for the collection of data while failing to provide cost benefit which could have been realized.</p><p>　　Other factors that may contribute to maintenance impr

95、ovement are: application of inexpensive sensor techniques and effective diagnostics to maintain equipment’s health; data coordination from multiple sources for analysis and decision making; a system for efficient exchang

96、e of information across T&D and substations; and experienced pool of trained professionals.</p><p>　　The management should be prepared to invest in staff and hardware/software to actively manage the main

97、tenance program. A team approach to RCM must be retained and the concept of RCM must be accepted in the organization.</p><p>　　In order to use appropriate software and hardware, education and training effort

98、s should be an integral part of this process. The understanding of the basics of utility’s maintenance program and the working knowledge of the tools required by the staff must be assured.</p><p>　　The key t

99、o sustaining a successful maintenance program is the development of a process that will ensure the continuance of maintenance program over a long period of time. It is necessary to periodically review and update the main

100、tenance program using a structured method.</p><p>　　7.CONCLUSION </p><p>　　Today, cutting operations and maintenance costs and preserving service reliability are the top priorities for managers

101、of utility transmission and distribution systems. The concept of RCM is sound and should provide utilities with a structured approach to a maintenance program with an optimum balance between cost of maintenance and relia