1、<p>　　Power Supply and Distribution System</p><p>　　ABSTRACT: The basic function of the electric power system is to transport the electric power towards customers. The l0kV electric distribution net is

2、a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, allcostumers expect to pay the lowest price for the highest reliability, but don'

3、;t consider that it's self-contradictory in the co-existence of economy and reliable.To improve the reliability of the power supply ne</p><p>　　KEYWORDS: power supply and distribution, power distribution

4、 reliability，reactive compensation, load distribution</p><p>　　The revolution of electric power system has brought a new big round construction,which is pushing the greater revolution of electric power techn

5、ique along with the application of new technique and advanced equipment. Especially, the combination of the information technique and electric power technique, to great ex- tent, has improved reliability on electric qual

6、ity and electric supply. The technical development decreases the cost on electric construction and drives innovation of electric network</p><p>　　Firstly, This dissertation introduces the building condition

7、of distribution automation(DA), and brings forward two typical construction modes on DA construction, integrative mode and fission mode .It emphasize the DA structure under the condition of the fission mode and presents

8、the system configuration, the main station scheme, the feeder scheme, the optimized communication scheme etc., which is for DA research reference.</p><p>　　Secondly, as for the (DA) trouble measurement, posi

9、tion, isolation and resume, This dissertation analyzes the changes of pressure and current for line problem, gets math equation by educing phase short circuit and problem position under the condition of single-phase and

10、works out equation and several parameter s U& , s I& and e I& table on problem . It brings out optimized isolation and resume plan, realizes auto isolation and network reconstruction, reduces the power off ra

11、nge and time and impr</p><p>　　Thirdly, electricity system state is estimated to be one of the key techniques in DA realization. The dissertation recommends the resolvent of bad measurement data and structur

12、e mistake on the ground of describing state estimate way. It also advances a practical test and judging way on topology mistake in state estimate about bad data test and abnormity in state estimate as well as the problem

13、 and effect on bad data from state measure to state estimate .As for real time monitor and control probl</p><p>　　Fourthly, about the difficulty for building the model of load forecasting, big parameter scat

14、ter limit and something concerned, the dissertation introduces some parameters, eg. weather factor, date type and social environment effect based on analysis of routine load forecasting and means. It presents the way for

15、 electricity load forecasting founded on neural network(ANN),which has been tested it’s validity by example and made to be good practical effect.</p><p>　　Fifthly, concerning the lack of concordant wave on p

16、reve nting concordant wave and non-power compensation and non-continuity on compensation, there is a topology structure of PWM main circuit and nonpower theory on active filter the waves technique and builds flat proof o

17、n the ground of Saber Designer and proves to be practical. Meanwhile, it analyzes and designs the way of non-power need of electric network tre- nds and decreasing line loss combined with DA, which have been tested its o

18、bjective</p><p>　　Sixthly, not only do the dissertation design a way founded on the magrginal electric price fitted to our present national electric power market with regards to future trends of electric pow

19、er market in China and fair trade under the government surveillance, that is group competitio n in short-term trade under the way of grouped price and quantity harmony, but also puts forward combination arithmetic, math

20、model of trading plan and safty economical restriction. It can solve the original contradic</p><p>　　The distribution network is an important link among the power system. Its neutral grounding mode and opera

21、tion connects security and stability of the power system directly. At the same time, the problem about neutral grounding is associated with national conditions, natural environment, device fabrication and operation. For

22、example, the activity situation of the thunder and lightning, insulating structure and the peripheral interference will influence the choice of neutral grounding mode Convers</p><p>　　The main work of this p

23、aper is to research and choice the neutral grounding mode of the l0kV distribution network. The neutral grounding mode of the l0kV network mainly adopts none grounding, grounding by arc suppressing coil, grounding by rea

24、ctance grounding and directly grounding. The best grounding mode is confirmed through the technology comparison. It can help the network run in safety and limit the earth electric arc by using auto-tracking compensate de

25、vice and using the line protection wi</p><p>　　Then, this paper researches and introduces some operation characteristics of the arc suppressing coil grounding mode of the l0kV distribution network. And then

26、the paper put emphasis on how to extinguish the earth electric arc effectively by utilizing the resonance principle. This paper combines the development of domestic and international technology and innovative achievement

27、, and introduces the computer earth protection and autotracking compensate device. It proves that the improved arc suppr</p><p>　　Finally, the paper summarizes this topic research. As a result of the dominat

28、ion of the arc suppressing coil grounding mode, it should be more popularized and applied in the distribution network in the future.The way of thinking, project and conclusions in this thesis have effect on the research

29、to choose the neutral grounding mode not only in I0kV distribution network but also in other power system.</p><p>　　The basic function of the electric power system is to transport the electric power towards

30、customers. The l0kV electric distribution net is a key point that connects the power supply with the electricity using on the industry, business and daily-life. For the electric power, all costumers expect to pay the low

31、est price for the highest reliability, but don't consider that it's self-contradictory in the co-existence of economy and reliable. To improve the reliability of the power supply network, w</p><p>　　

32、First, the thesis introduces as the different line modes in the l0kV electric distribution net and in some foreign countries. Making it clear tow to conduct analyzing on the line mode of the electric distribution net, an

33、d telling us how important and necessary that analyses are.</p><p>　　Second, it turns to the necessity of calculating the number of optimization subsection, elaborating how it influences on the economy and r

34、eliability. Then by building up the calculation mode of the number of optimization subsection it introduces different power supply projects on the different line modes in brief. Third, it carries on the calculation and a

35、nalyses towards the reliability and economy of the different line modes of electric distribution net, describing drafts according by the calcu</p><p>　　At last, the article make conclusion on the economy and

36、 reliability of different line modes, as well as, its application situation. Accordion to the actual circumstance, the thesis puts forward the beneficial suggestion on the programming and construction of the l0kV electri

37、c distribution net in all areas in foshan. Providing the basic theories and beneficial guideline for the programming design of the 10kVelectric distribution net and building up a solid net, reasonable layout, qualified s

38、afe a</p><p>　　References </p><p>　　[1] Wencheng Su. Factories power supply [M]. Machinery Industry Publishing House. 1999.9[2] Jiecai Liu. Factories power supply design guidance [M]. Machinery

39、 Industry Publishing House.1999.12[3] Power supply and distribution system design specifications[S].China plans Press. 1996[4] Low-voltage distribution design specifications [S].China plans Press. 1996.6</p>&l

40、t;p><b>　　供配電系統(tǒng)</b></p><p>　　摘要：電力系統(tǒng)的基本功能是向用戶輸送電能。lOkV配電網(wǎng)是連接供電電源與工業(yè)、商業(yè)及生活用電的樞紐，其網(wǎng)絡(luò)龐大及復(fù)雜。對(duì)于所有用戶都期望以最低的價(jià)格買到具有高度可靠性的電能。然而，經(jīng)濟(jì)性與可靠性這兩個(gè)因素是互相矛盾的。要提高供電網(wǎng)絡(luò)的可靠性就必須增加網(wǎng)絡(luò)建設(shè)投資成本。但是，如果提高可靠性使用戶停電損失的降低小于用于提高可靠性所

41、增加的投資，那么這種建設(shè)投資就沒有價(jià)值了。通過計(jì)算電網(wǎng)的投資和用戶停電的損失，最終可找到一個(gè)平衡點(diǎn)，使投資和損失的綜合經(jīng)濟(jì)性最優(yōu)。</p><p>　　關(guān)鍵詞：供配電，供電可靠性，無功補(bǔ)償，負(fù)荷分配</p><p><b>　　1 引言</b></p><p>　　電力體制的改革引發(fā)了新一輪大規(guī)模的電力建設(shè)熱潮，從而極大地推動(dòng)了電力技術(shù)革命，新

42、技術(shù)新設(shè)備的開發(fā)與應(yīng)用日新月異特別是信息技術(shù)與電力技術(shù)的結(jié)合在很大程度上提高了電能質(zhì)量和電力供應(yīng)的可靠性。由于技術(shù)的發(fā)展又降低了電力建設(shè)的成本，進(jìn)而推動(dòng)了電網(wǎng)設(shè)備的更新?lián)Q代。本文就是以此為契機(jī)，以國(guó)內(nèi)外配電自動(dòng)化中一些前沿問題為內(nèi)容，以配電自動(dòng)化建設(shè)為背景，對(duì)當(dāng)前電力系統(tǒng)的熱點(diǎn)技術(shù)進(jìn)行一些較深入的探討和研究。主要完成了如下工作：</p><p>　　(1)提出了配電自動(dòng)化建設(shè)的兩個(gè)典型模式，即―體化模式和分立化模

43、式。側(cè)重分析了分立模式下的配電自動(dòng)化系統(tǒng)體系結(jié)構(gòu)，給出了軟硬件配置主站選擇管理模式、最佳通訊方式等是本文研究的前提和實(shí)現(xiàn)平臺(tái)。</p><p>　　(2)針對(duì)配電自動(dòng)化中故障測(cè)量、定位與隔離以及供電恢復(fù)這一關(guān)鍵問題，分析了線路故障中電壓電流等電量的變化，導(dǎo)出了相間短路工況下故障定位的數(shù)學(xué)描述方程，并給出了方程的解以及故障情況下幾個(gè)重要參數(shù)s 、U&s 、I& e 、I& 。選擇表通過對(duì)故障

44、的自動(dòng)診斷與分析得出了優(yōu)化的隔離和恢復(fù)供電方案。自動(dòng)實(shí)現(xiàn)故障快速隔離與網(wǎng)絡(luò)重構(gòu)，減少了用戶停電范圍和時(shí)間，有效提高配網(wǎng)供電可靠性。文中還給出了故障分段判斷以及網(wǎng)絡(luò)快速重構(gòu)的軟件流程和使用方法。</p><p>　　(3)狀態(tài)估計(jì)是實(shí)現(xiàn)配電自動(dòng)化中關(guān)鍵技術(shù)之一。本文在闡述狀態(tài)估計(jì)方法基礎(chǔ)上給出了不良測(cè)量數(shù)據(jù)的識(shí)別和結(jié)構(gòu)性錯(cuò)誤的識(shí)別方法，針對(duì)狀態(tài)估計(jì)中數(shù)據(jù)對(duì)基于殘差的壞數(shù)據(jù)檢測(cè)和異常以及狀態(tài)量中壞數(shù)據(jù)對(duì)狀態(tài)估計(jì)的影響

45、及存在的問題，提出了狀態(tài)估計(jì)中拓?fù)溴e(cuò)誤的一種實(shí)用化檢測(cè)和辯識(shí)方法。針對(duì)竊電漏計(jì)電費(fèi)問題，獨(dú)創(chuàng)性提出一種通過電量突變和異常分析防止竊電的新方法，并在濰坊城區(qū)配電得到驗(yàn)證。</p><p>　　(4)針對(duì)配電網(wǎng)負(fù)荷預(yù)測(cè)建模困難，參數(shù)離散度大以及相關(guān)因素多等問題。本文在分析常規(guī)負(fù)荷預(yù)測(cè)模型及方法基礎(chǔ)上，引入了氣象因素日期類型、社會(huì)環(huán)境影響等參數(shù)，給出了基于神經(jīng)網(wǎng)絡(luò)的電力負(fù)荷預(yù)測(cè)方法，實(shí)例驗(yàn)證了方法的正確性。</p

46、><p>　　(5)針對(duì)無源濾波在抑制諧波和無功補(bǔ)償方面的不足，以及補(bǔ)償度的不連續(xù)性，本文提出了一種PWM 主電路拓樸結(jié)構(gòu)和基于無功功率理論的有源濾波方案，建立了基于Saber Designer 仿真平臺(tái)仿真分析，證明了方案的可行性。同時(shí)結(jié)合配電自動(dòng)化技術(shù)，對(duì)配電網(wǎng)動(dòng)態(tài)無功優(yōu)化補(bǔ)償和降低線損的方法進(jìn)行了設(shè)計(jì)、分析。通過實(shí)例計(jì)算驗(yàn)證了其客觀的經(jīng)濟(jì)效益。</p><p>　　(6)針對(duì)中國(guó)電力市場(chǎng)

47、未來的發(fā)展趨勢(shì)以及政府監(jiān)管下的電力市場(chǎng)公平交易，設(shè)計(jì)了一種適合我國(guó)電力市場(chǎng)現(xiàn)狀。按照電價(jià)分組、電量協(xié)調(diào)分組、競(jìng)價(jià)的短期電力交易模式，給出了基于邊際電價(jià)的機(jī)組組合算法，制訂交易計(jì)劃的數(shù)學(xué)模型以及安全經(jīng)濟(jì)約束等，在競(jìng)爭(zhēng)比例逐步提高的情況下，能夠較好地解決原有中長(zhǎng)期合同電價(jià)和短期競(jìng)爭(zhēng)電價(jià)的矛盾，減少電廠不公平的收益差異，同時(shí)也可在電力市場(chǎng)全網(wǎng)的負(fù)荷曲線上對(duì)所有電廠進(jìn)行限量?jī)?yōu)化，減少總的系統(tǒng)購(gòu)電費(fèi)用。</p><p>&

48、lt;b>　　2 配電網(wǎng)分析</b></p><p>　　配電網(wǎng)是電力系統(tǒng)中的一個(gè)重要環(huán)節(jié)，配電網(wǎng)接地方式和安全運(yùn)行直接關(guān)系到電力系統(tǒng)的安全和穩(wěn)定。而接地方式的選擇，是與本國(guó)國(guó)情、自然環(huán)境、設(shè)備制造和運(yùn)行水平等有關(guān)的，例如，雷電的活動(dòng)情況、絕緣結(jié)構(gòu)的設(shè)計(jì)、對(duì)周邊的干擾等因素，都會(huì)影響中性點(diǎn)接地方式的選擇；反過來，中性點(diǎn)接地方式對(duì)電力系統(tǒng)的設(shè)計(jì)、運(yùn)行、調(diào)試以及發(fā)展都有很大影響。一般在電壓等級(jí)較高的

49、系統(tǒng)中，絕緣費(fèi)用在設(shè)備總價(jià)格中占相當(dāng)大的比重，降低絕緣水平帶來的經(jīng)濟(jì)效益很顯著，通常就采用中性點(diǎn)直接接地的方式，而采用自動(dòng)重合閘來保證供電可靠性；相反，在電壓等級(jí)較低的系統(tǒng)中，通常都采用中性點(diǎn)不接地的方式來提高供電可靠性。因此，在綜合考慮供電可靠性、安全因素、過電壓因素、繼電保護(hù)的選擇、投資費(fèi)用等各方面因素的情況下，來論證正確選擇配電網(wǎng)接地方式的重要性，以及如何不斷開發(fā)，利用新型接地裝置來應(yīng)用在配電網(wǎng)接地系統(tǒng)中是當(dāng)今配電網(wǎng)接地方式的一個(gè)

50、重要課題。</p><p>　　本文主要工作是對(duì)lOkV配電網(wǎng)接地方式進(jìn)行研究和比較選擇。分別論述各類接地方式的優(yōu)缺點(diǎn)，主要有國(guó)內(nèi)外比較常用的中性點(diǎn)不接地方式、中性點(diǎn)經(jīng)消弧線圈接地方式(也稱諧振接地方式)、中性點(diǎn)電阻接地方式、中性點(diǎn)直接接地方式。通過技術(shù)比較確定最優(yōu)接地方式，還利用一種近幾年研究開發(fā)的，應(yīng)用在諧振接地方式中的自動(dòng)跟蹤補(bǔ)償裝置，再配以靈敏的小電流接地選線保護(hù)，能夠有效限制電網(wǎng)的故障接地電弧，更有利于

51、電網(wǎng)的安全運(yùn)行。本文首先對(duì)配電網(wǎng)各類接地方式做深入的研究。全面介紹國(guó)內(nèi)外幾種常用的中性點(diǎn)接地方式的運(yùn)行特性，通過技術(shù)經(jīng)濟(jì)比較對(duì)不同的接地方式進(jìn)行綜合評(píng)價(jià)，再結(jié)合不同的接地方式的發(fā)展前景得出結(jié)論，優(yōu)化了的諧振接地方式表現(xiàn)出很大的發(fā)展?jié)摿Α?lt;/p><p>　　然后，本文對(duì)lOkV配電網(wǎng)中性點(diǎn)諧振接地方式的運(yùn)行特性進(jìn)行了研究和介紹。從限制故障接地電弧的危害出發(fā)，重點(diǎn)論述如何利用電流諧振原理，有效熄滅故障接地電弧等。接

52、著，本文結(jié)合國(guó)內(nèi)外科技的發(fā)展和創(chuàng)新成果，對(duì)諧振接地優(yōu)化方式中的微機(jī)接地保護(hù)性和自動(dòng)跟蹤補(bǔ)償裝置進(jìn)行全面的分析與論述，說明諧振接地優(yōu)化方式在供電可靠性、人身安全、設(shè)備安全和通信干擾等方面，具有較好的運(yùn)行特性，既解決了小電流接地系統(tǒng)接地保護(hù)的選擇性，又實(shí)現(xiàn)了自動(dòng)調(diào)諧，使此種接地方式成為配電網(wǎng)比較理想的中性點(diǎn)接地方式。本文同時(shí)還對(duì)諧振接地方式實(shí)施技術(shù)進(jìn)行了研究，包括消弧線圈的參數(shù)選擇、安裝、調(diào)整、運(yùn)行與維護(hù)等內(nèi)容。</p>&l

53、t;p>　　最后，本文總結(jié)了本課題研究的內(nèi)容。諧振接地籍助微機(jī)技術(shù)的支持，近些年來國(guó)內(nèi)外均在進(jìn)行優(yōu)化，優(yōu)化諧振接地技術(shù)是提高供電可靠性、保護(hù)人身安全、設(shè)備安全和電磁環(huán)境等的一項(xiàng)合理的重要技術(shù)手段，而諧振接地實(shí)施技術(shù)更充分發(fā)揮諧振接地方式的功能，使諧振接地方式具有更好的技術(shù)經(jīng)濟(jì)指標(biāo)。隨著電網(wǎng)的不斷發(fā)展和豐富的實(shí)踐結(jié)果表明，以諧振接地方式為代表的小電流接地方式優(yōu)于其他接地方式，這是配電網(wǎng)的中性點(diǎn)接地方式發(fā)展的總趨勢(shì)，在今后的配電網(wǎng)接地

54、方式中應(yīng)推廣應(yīng)用。</p><p>　　本論文提出的思路、方案和結(jié)論不僅對(duì)于lOkV配電網(wǎng)中性點(diǎn)接地方式選擇研究、實(shí)際工程應(yīng)用具有實(shí)際的參考作用，對(duì)于其他電壓等級(jí)中性點(diǎn)接地方式選擇同樣具有借鑒的作用。</p><p>　　電力系統(tǒng)的基本功能是向用戶輸送電能。lOkV配電網(wǎng)是連接供電電源與工業(yè)、商業(yè)及生活用電的樞紐，其網(wǎng)絡(luò)龐大及復(fù)雜。對(duì)于所有用戶都期望以最低的價(jià)格買到具有高度可靠性的電能。然

55、而，經(jīng)濟(jì)性與可靠性這兩個(gè)因素是互相矛盾的。要提高供電網(wǎng)絡(luò)的可靠性就必須增加網(wǎng)絡(luò)建設(shè)投資成本。但是，如果提高可靠性使用戶停電損失的降低小于用于提高可靠性所增加的投資，那么這種建設(shè)投資就沒有價(jià)值了。通過計(jì)算電網(wǎng)的投資和用戶停電的損失，最終可找到一個(gè)平衡點(diǎn)，使投資和損失的綜合經(jīng)濟(jì)性最優(yōu)。論文針對(duì)配電網(wǎng)各種接線模式的特點(diǎn)，就各種接線模式的經(jīng)濟(jì)性和可靠性進(jìn)行了分析。</p><p><b>　　3 小結(jié)</

56、b></p><p>　　論文首先介紹lOkV配電網(wǎng)各種典型的接線模式和國(guó)外幾個(gè)國(guó)家的典型接線模式，然后確定配電網(wǎng)接線模式分析的思路，明確進(jìn)行分析的必要性和重要性。再提出最優(yōu)分段數(shù)計(jì)算的必要性，闡述最優(yōu)分段數(shù)對(duì)經(jīng)濟(jì)性和可靠性的影響，然后建立最優(yōu)分段數(shù)計(jì)算模型，并簡(jiǎn)單介紹各種接線模式的供電方案。而后對(duì)配電網(wǎng)各種接線模式的可靠性和經(jīng)濟(jì)性進(jìn)行了計(jì)算和分析，通過計(jì)算并描繪的各種圖表。并對(duì)最優(yōu)分段數(shù)作了分析和討論。文

57、章最后對(duì)各種接線模式的經(jīng)濟(jì)性和可靠性進(jìn)行總結(jié)，分析了各種接線模式各自的優(yōu)點(diǎn)和缺點(diǎn)，其適用情況。并結(jié)合實(shí)際情況針對(duì)lOkV配電網(wǎng)的規(guī)劃和建設(shè)提出有益的建議。為lOkV配電網(wǎng)的規(guī)劃設(shè)計(jì)及為建成網(wǎng)架堅(jiān)實(shí)、布局合理、管理科學(xué)、能夠安全、優(yōu)質(zhì)、高效運(yùn)行的配電網(wǎng)提供理論的依據(jù)和有益的指引。</p><p><b>　　參考文獻(xiàn)</b></p><p>　?。?］蘇文成.工廠供電[