【正文】 電能損耗和電壓損失，同時(shí)提高了供電電壓的質(zhì)量。特別對(duì)主接線(xiàn)的選擇,變壓器的選擇,還有一些電氣設(shè)備如斷路器、電流互感器、電壓互感器等的選擇校驗(yàn)作了詳細(xì)的說(shuō)明和分析。本次設(shè)計(jì)的內(nèi)容緊密結(jié)合實(shí)際，通過(guò)查找大量相關(guān)資料，設(shè)計(jì)出符合當(dāng)前要求的變電所。通過(guò)本次設(shè)計(jì)，使我對(duì)電氣工程及其自動(dòng)化專(zhuān)業(yè)的主干課程有一個(gè)較為全面，系統(tǒng)的掌握，增強(qiáng)了理論聯(lián)系實(shí)際的能力，提高了工程意識(shí)，鍛煉了我獨(dú)立分析和解決電力工程設(shè)計(jì)問(wèn)題的能力，為未來(lái)的實(shí)際工作奠定了必要的基礎(chǔ)。關(guān)鍵詞：電力負(fù)荷；功率補(bǔ)償；短路電流；電氣設(shè)備；主接線(xiàn)INTRODUCTIONThis paper mainly introduces the design of 35kV substation in a prehensive Metallurgy design idea, to power supply reliability, economic demand according to the electric power system of steel plant, have made overall and prehensive analysis to the electric power system of our factory according to the distribution situation of the load nature , size of load and load of the steel plant, have explained the theoretical foundation realized in transformer substation.In the design, based on the scope and basis for the design of information, and set up a production and development suited to their own needs electricity power system of the enterprise was offered by two independent sources, each with their own power back to a 35 KV overhead electricity lines to the factory. The Primary Side in substations power supply system adopted the connection with single bus with a tie, each bus was connected to a Secondaryside of power supply system adopted the connection with single bus with a tie too. In addition to improving the reliability of power supply,join in a automatic input device of spare power on 6KV bus so that the two transformers can backup each other. Aiming to the features of the load variation of Metallurgical Enterprise installed pensation capacitor on the 6KV bus with the way of High Voltage Concentrating Workless Compensation to reduce the loss of electric energy by improving the natural power actor of supply work in Metallurgical Enterprise.It discusses the choice of main wiring, high pressure equipment and all kinds of the protection of relay, the calculation of load, short current and so on in detail, especially, the choice of main wiring, transformer and some electric equipment such as circuit breaker, current and Voltage sensor. It shows main wiring of substation, the distribution of plane and some protection equipment of high and low Voltage by the graphics of CAD.This design is closely related to reality in order to design the suitable substation by studying a lot of materials. The design not only adopts some stableform and general protections but also Thinking of the introduction of automatic control. The synthetical automation system of electric power superVision, which can make workers on duty control the situation of substation timely, operate the equipments directly, know the breakdown and deal with it without delay, so that the system of power supply is scientific and standard in management. What’s more, it can exchange data with other automatic systems and giVe full play to whole adVantage in order to manage information in all systems as a whole.Through this design, so that I electrical engineering and automation professional courses are the backbone of a more prehensive and systematic control and enhanced the ability to integrate theory with practice, raising awareness of the project, I tempered the independent analysis and engineering design to solve the power problem Capacity, the actual work for the future lay the necessary foundation.KEYWORDS: Electric load。Short out in the electric current。Mainly wire某冶金機(jī)電設(shè)備制造廠總降壓變電所的設(shè)計(jì)電氣工程及其自動(dòng)化 方澤川 202211331107指導(dǎo)老師：王筱珍第 1 章 緒論電是最基本的能源，不僅人民生活需要電，企業(yè)生產(chǎn)需要電，整個(gè)人類(lèi)社會(huì)的進(jìn)步更需要電。電力工業(yè)的發(fā)展水平，是一個(gè)國(guó)家經(jīng)濟(jì)發(fā)達(dá)程度的重要標(biāo)志。我國(guó)的電力工業(yè)已居世界前列，但與發(fā)達(dá)國(guó)家相比還是有一定的差距，我們?nèi)司娏克竭€很低，電力工業(yè)分布也不均勻，還不能滿(mǎn)足國(guó)民經(jīng)濟(jì)發(fā)展的需要。為了使我國(guó)電力工業(yè)趕上世界電力技術(shù)的發(fā)展水平，從 21 世紀(jì)一開(kāi)始，我國(guó)就進(jìn)一步加強(qiáng)在電網(wǎng)安全、穩(wěn)定、經(jīng)濟(jì)運(yùn)行、電力系統(tǒng)的自動(dòng)化調(diào)度與管理、電力通信、網(wǎng)絡(luò)技術(shù)、繼電保護(hù)等領(lǐng)域開(kāi)展研究，尤其注意完善電力市場(chǎng)，研究電力市場(chǎng)的技術(shù)支持系統(tǒng)，促進(jìn)我們的電力工業(yè)不斷前進(jìn)。我們知道,電能是現(xiàn)代工業(yè)生產(chǎn)的主要能源和動(dòng)力，工業(yè)生產(chǎn)應(yīng)用電能和實(shí)現(xiàn)電氣化以后,能大大增加產(chǎn)量,提高產(chǎn)品質(zhì)量,提高勞動(dòng)生產(chǎn)率,降低生產(chǎn)成本,減輕工人的勞動(dòng)強(qiáng),改善工人的勞動(dòng)條件,有利于實(shí)現(xiàn)生產(chǎn)過(guò)程自動(dòng)化。 第 2 章 負(fù)荷計(jì)算及無(wú)功功率補(bǔ)償設(shè)計(jì)計(jì)算計(jì)算負(fù)荷是根據(jù)已知的工廠的用電設(shè)備安裝容量確定的、預(yù)期不變的最大假想負(fù)荷。負(fù)荷計(jì)算過(guò)小,則依此選用的設(shè)備和載流部份有過(guò)熱危險(xiǎn),輕者使線(xiàn)路和配電設(shè)備壽命降低,重,則造成設(shè)備的浪費(fèi)和投資的增大。 負(fù)荷計(jì)算目前負(fù)荷計(jì)算常用需要系數(shù)法、二項(xiàng)式法、利用系數(shù)法,前二種方法在國(guó)內(nèi)設(shè)計(jì)單位的使用最為普遍。本設(shè)計(jì)mK選用需用系數(shù)法。 表 21 原始負(fù)荷數(shù)據(jù)表變電所 車(chē)間或用電單位 設(shè)備容量KVA 需要系數(shù) ?costan一號(hào)變電所 鑄鋼車(chē)間 2022 鑄鐵車(chē)間 1000 沙庫(kù) 110 鎦焊車(chē)間 1200 1 號(hào)水泵房 28 空壓站 390 鍛造車(chē)間 320 模型車(chē)間 192 料場(chǎng) 35 綜合樓 30 1 1四號(hào)變電所廠區(qū)照明 20 1 1鍋爐房 300 2 號(hào)水泵房 28 倉(cāng)庫(kù) 88 污水提升站 14 六號(hào)變電所 變壓器修造車(chē)間 680 七號(hào)變電所 電氣裝配車(chē)間 350 電弧爐 2*125 工頻爐 2*300 空壓機(jī) 2*250 各車(chē)間高壓負(fù)荷試驗(yàn)變壓器 2*100 負(fù)荷計(jì)算過(guò)程如下： （2edcaPK?1）為同時(shí)系數(shù)，由表格提供 dK （ 2?tanP= Qc2） osSca?（23）， 也由表格提供?tancos將各變電所各自的數(shù)據(jù)填上，得到表 22。用電設(shè)備組的計(jì)算負(fù)荷，是指用電設(shè)備組從供電系統(tǒng)中取用的半個(gè)小時(shí)最大負(fù)荷 。因此在確定多組用電設(shè)備的計(jì)算負(fù)荷時(shí)，應(yīng)結(jié)合具體情況對(duì)其有功負(fù)荷和無(wú)功負(fù)荷分別計(jì)入一個(gè)同時(shí)系數(shù) 和 PK?q在此，先小計(jì)一下表 22 用電設(shè)備的有功負(fù)載和無(wú)功負(fù)載，得到 =4122 KW , =4109 Kvar，caP?caQ取 和 都為 ?q所以 P= =4109=3698 KvarQ KV因此，變電所需裝設(shè)無(wú)功補(bǔ)償裝置，對(duì)功率因數(shù)進(jìn)行人工補(bǔ)償。按 GB8022795《并聯(lián)電容裝置設(shè)計(jì)規(guī)范》規(guī)定：高壓電容器組宜采用單星形接線(xiàn)或雙星形結(jié)線(xiàn)。補(bǔ)償后總降壓變電所主變壓器二次母線(xiàn)上的計(jì)算負(fù)荷為 2c2)(PS??? = 4016 kV對(duì)供有大量一、二級(jí)負(fù)荷的變電所宜采用兩臺(tái)變壓器，以便當(dāng)一臺(tái)變壓器發(fā)生故障或檢修時(shí)，另一臺(tái)變壓器能對(duì)一、二級(jí)負(fù)荷繼續(xù)供電。（2）對(duì)季節(jié)性負(fù)荷或晝夜負(fù)荷變動(dòng)較大而宜采用經(jīng)濟(jì)運(yùn)行方式的變電所，也可考慮采用兩臺(tái)變壓器。但是負(fù)荷集中而容量相當(dāng)大的變電所，為三級(jí)負(fù)荷，也可以采用兩臺(tái)或以上變壓器。本設(shè)計(jì)的實(shí)際情況是，工廠設(shè)備全部為二級(jí)負(fù)荷，并且集中負(fù)荷較大。 主變壓器容量的確定為提高供電的可靠性，本設(shè)計(jì)在 6KV 側(cè)的分段母線(xiàn)上安裝備用電源自動(dòng)投入裝置，使兩臺(tái)變壓器互為備用。這種方案能滿(mǎn)足正常工作時(shí)經(jīng)濟(jì)運(yùn)行的要求，又能在故障情況下承擔(dān)全部負(fù)荷，提高了供電系統(tǒng)的可靠性，是比較合理的備用方式。變電所的環(huán)境為一般環(huán)境，可選用油浸式變壓器。變壓器的數(shù)據(jù)見(jiàn)表 31。它由各種電力設(shè)備(隔離開(kāi)關(guān)、避雷器、斷路器、互感器、變壓器等)及其連接線(xiàn)組成。主接線(xiàn)是否合理,對(duì)變電所設(shè)備選擇和布置,運(yùn)行的靈活性、安全性、可靠性和經(jīng)濟(jì)性,以及繼. 在圖上所有電器均以新的國(guó)家標(biāo)準(zhǔn)圖形符號(hào)表示，按它們的正常狀態(tài)畫(huà)出。對(duì)于圖中的斷路器和隔離開(kāi)關(guān)，是畫(huà)出它們的斷開(kāi)位置。從主接線(xiàn)圖上我們可了解變電所設(shè)備的電壓、電流的流向、設(shè)備的型號(hào)和數(shù)量、變電所的規(guī)模及設(shè)備間的連接方式等，因此，主接線(xiàn)圖是變電所的最主要的圖紙之一。變電所不管是樞紐變電所、地區(qū)變電所、終端變電所、企業(yè)變電所還是分支變電所，由于它們?cè)陔娏ο到y(tǒng)中的地位和作用不同，對(duì)主接線(xiàn)的可靠性、靈活性、經(jīng)濟(jì)性的要求也不同。應(yīng)根據(jù)負(fù)荷的大小及分布負(fù)荷增長(zhǎng)速度和潮流分布，并分析各種可能的運(yùn)行方式，來(lái)確定主接線(xiàn)的形式以及所連接電源數(shù)和出線(xiàn)回?cái)?shù)。(4) 考慮主變臺(tái)數(shù)對(duì)主接線(xiàn)的影響變電所主變的容量和臺(tái)數(shù)，對(duì)變電所主接線(xiàn)的選擇將會(huì)產(chǎn)生直接的影響。而容量小的變電所，其傳輸容量小，對(duì)主接線(xiàn)的可靠性、靈活性的要求低。電氣主接線(xiàn)的設(shè)計(jì)要根據(jù)備用容量的有無(wú)而有所不同，例如，當(dāng)斷路器或母線(xiàn)檢修時(shí)，是否允許線(xiàn)路、變壓器停運(yùn)；當(dāng)線(xiàn)路故障時(shí)否允切除線(xiàn)路、變壓器的數(shù)量等，都直接影響主接線(xiàn)的形式。并應(yīng)綜合考慮供電可靠、運(yùn)行靈活、操作檢修方便、投資節(jié)約和便于過(guò)渡或