【正文】
.............................. 72 第一節(jié) 繼電保護(hù)配置 ................................................................................................. 73 第二節(jié) 自動(dòng)裝置配置 ................................................................................................. 76 第八章 防雷與接地的設(shè)計(jì) .................................................................................................... 83 第一節(jié) 防雷設(shè)計(jì) ........................................................................................................ 83 第二節(jié) 接地裝置 ........................................................................................................ 92 專題:繼電保護(hù)新技術(shù)研究 ........................................................................................................ 93 致 謝 ................................................................................................................................ 98 參考文獻(xiàn) ............................................................................................................................. 99 第 1 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 第一章 設(shè)計(jì)任務(wù)介紹 第一節(jié) 原始資料 一、電氣一次部分的設(shè)計(jì)情況 該變電所為 110/,所內(nèi)設(shè)計(jì) MVA 及40MVA 主變各一臺, 2 回 110kV 架空進(jìn)線, 4 回 35kV 出線及 8 回 10kV 出線。 Abstract: Power system planning, design to construction, to operation and management is a huge content and skills covered in this course is the theoretical basis of this huge system engineering in order to ensure the 第 3 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) safe operation of the power system, reliability of supply, we conducted the course design includes the general principles of the power system, the contents of the program, must short circuit calculation, reactive power pensation and protection. Substation is an important ponent of the power system, which directly affects the safety and economic operation of the entire power system, contact the power plants and the middle section of the user plays a role in the transformation and distribution of electric energy, power equipment and power distribution work according to a electricity from the power system, through its transformation, distribution, transmission and protection functions, and then to electrical energy safe, reliable, economic transportation to the conversion of electrical equipment substation must change the traditional design and control mode, to adapt to the modern power system, the development of modern power industrial production and social main electrical wiring is the main part of power plant substation electrical equipment, the formulation of the main electrical connection is directly related to the whole plant (The) to select the layout of power distribution equipment, relay protection and automatic devices to determine part of the investment of the electrical substationThe size of the decisive factors. This design is the construction of a 110KV stepdown substation, First of all, according to the main wiring economical and reliable, run flexible asked to select the voltage level of the wiring in the technical aspects and economic aspects, select the flexible optimal by a shortcircuit current calculation, according to shortcircuit point to calculate the shortcircuit steadystate current and shortcircuit impulse current when short circuit occurs, the voltage level of the bus, the shortcircuit steadystate current and the impact of current from the threephase shortcircuit selection, then the voltage level of the rated voltage and maximum continuous operating current carefully read the original material, analysis of materials, reference reading power plant electrical part of the course design reference, the power grid and power system, once the power plant wiring and electrical equipment and High Voltage 35 ~110kV unattended substation typical design reference books and under the guidance of the instructor, after careful calculation, plete the graduation project. 第 4 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 關(guān) 鍵詞:電力系統(tǒng),短路計(jì)算,繼電保護(hù),變電站,電氣主接線, 110KV降壓變 Keywords: power system, short circuit calculations, relay protection, substation, electrical wiring, 110KV stepdown change 前 言 電力事業(yè)的日益發(fā)展緊系著國計(jì)民生。 變電站是電力系統(tǒng)的一個(gè)重要組成部分, 它直接影響整個(gè)電力系統(tǒng)的安全與經(jīng)濟(jì)運(yùn)行,是聯(lián)系發(fā)電廠和用戶的中間 節(jié)起著變換和分配電能的作用, 由電力設(shè)備及配電網(wǎng)絡(luò)按一定的接線方式所組成。他從電力系統(tǒng)中取得電能,通過其變換、分配、輸送與保護(hù)等功能,然后將電能安全、可靠、經(jīng)濟(jì)的輸送到每個(gè)用電設(shè)備的轉(zhuǎn)換場所。它的發(fā)展水平和電氣的程度是衡量一個(gè)國家的國民經(jīng)濟(jì)發(fā)展水平及其社會現(xiàn)代化水平高低的一個(gè)重要標(biāo)志。 主接可以考慮 110kV 側(cè)采用內(nèi)橋、外僑、單母分段接線, 35kV 可以考慮單母分段、雙母線接線, 10kV 可以考慮單母分段、雙母線接線。 %/177。 要求: 1) 熟悉國家能源開發(fā)策略和有關(guān)的技術(shù)規(guī)程、規(guī)定、導(dǎo)則等,樹立供電必 第 5 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 須安全、可靠、經(jīng)濟(jì)的觀點(diǎn); 2) 掌握變電站初步設(shè)計(jì)的基本方法和主要內(nèi)容; 3) 熟練電力系統(tǒng)的基本計(jì)算; 4) 學(xué)習(xí)工程設(shè)計(jì)說明書的撰寫。 優(yōu)點(diǎn): 1 .用斷路器把 母線分段后,對重要的用戶可以從不同段引出兩個(gè)回路,有兩個(gè)電源供電; 2 .任一段母線或母線隔離開關(guān)檢修,只停該段,其他段可繼續(xù)供電,減小了停電范圍。當(dāng)有雙回架空線路時(shí),可以順序布置,致使連接不同段的母線不會出現(xiàn)向單母分段那樣出線導(dǎo)致交叉跨越現(xiàn)象; 4. 便于試驗(yàn)。 缺點(diǎn): ( 1)其中一回線路檢修或故障時(shí),有一臺變壓器短時(shí)停運(yùn),操作較復(fù)雜; ( 2)變壓器側(cè)斷路器檢修時(shí),變壓器需較長時(shí)間停運(yùn)。 第 11 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 五、設(shè)計(jì)標(biāo)準(zhǔn)化 同類型變電所采用相同的主接線形式 ,可使主接線規(guī)范化、標(biāo)準(zhǔn)化 ,有利于系統(tǒng)運(yùn)行和設(shè)備檢修。 方案三 110kV 采用外橋接線; 35kV 采用雙母接線; 10kV 采用單母分段接線。 第 16 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 方案四 110kV采用內(nèi)橋接線; 35kV采用單母分段接線; 10kV采用雙母線接線。 35kV和 10kV 側(cè)采用單母分段接線,母線、隔離開關(guān)檢修僅停一半,提高了其靈活性。 35kV 和10kV 側(cè)的靈活性優(yōu)點(diǎn)同方案一。 缺點(diǎn): 110kV 側(cè)和 10kV 側(cè)靈活性缺點(diǎn)各自同方案一所述。其中一回線路檢修或故障時(shí),其余部分不受影響,操作較簡單。 110kV 35kV 10kV Ⅱ Ⅰ Ⅰ Ⅱ 第 21 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 四、下面進(jìn)行經(jīng)濟(jì)性比較 35kV 的出線一般在 8 回,而任務(wù)書 35kV 的出線是 4 回,方案三采用的是雙母線接線,明顯增加了刀閘,投資較大,成本較高,具體比較如下: 110kV 10kV 35kV 方案一 一樣 高 一樣 方案三 低 五、 最終確定最佳方案是 方案一 110kV Ⅰ Ⅱ 35kV Ⅱ Ⅰ 10kV 1T2T 第 22 頁 共 100 頁 110kV 降壓變電站電氣部分畢業(yè)設(shè)計(jì) 第三章 短路計(jì)算 所謂短路,是指電力系統(tǒng)正常運(yùn)行情況以外的相與相之間或相與地之間的非正常連接。如電力系統(tǒng)中性點(diǎn)接地方式的選擇,變壓器接地點(diǎn)的位置和臺數(shù),對鄰近的通訊系統(tǒng)是否會產(chǎn)生較大的干擾,接地裝置的跨步電壓、接觸電壓的計(jì)算等都需要以多種運(yùn)行方式下的短路電流值為依據(jù)。 179。 =﹣ XT1Ⅲ =1001)(ⅢKU179。 1