摘要:本設計是一個小型火力發電廠電氣部分的設計，針對一個發電廠電氣部分設計而言，電氣主接線在發電廠電氣設計中扮演著重要的角色，因為主接線的確定對整個電力系統的運行以及發電廠、變電所運行的可靠性、靈活性和經濟性有著密切的關聯。同時，電氣主接線的設計對選擇各種電氣設備的型號也至關重要，電氣設備的合理選擇能確保各種繼電保護得以實現，從而保證電網的安全運行。

　　　本次設計主要是針對一個新建小型凝汽式火力發電廠，主要裝設1臺QF-25-2型發電機和1臺QFQ-50-2型發電機，所發出的額定電壓都為10.5KV,規定出線回路數為4回，輸送的距離分別為：25km、50km、75km、100km。此次設計的主要內容是給定一份原始資料，然后通過分析原始資料，對主變壓器進行選擇，最終設計出相對較為合理的電氣主接線連接方式。然后根據電氣主接線進行相應的短路電流的計算、各種電氣設備的選擇與校驗，同時對發電機、變壓器、輸電線路做出相應的繼電保護及對整個電廠采取防雷保護的初步設計，最后根據自己的設計畫出與之相對應的主接線圖。

關鍵詞：電氣主接線；電氣設備；繼電保護；防雷保護

Abstract:This is a design of the electric parts to small coal-fired power plants , according to this part, the main electrical wiring plays an important role in electrical design, because the determine of main wiring are closely related to the operation of the power system and reliability, flexibility and economy in power plants, substation operation. At the same time, it is the also important for main electrical wiring design to choose the type of electrical equipment, the reasonable selection of electrical equipment can ensure all kinds of relay protection can be realized, so as to ensure the safe operation of the power grid.

　　　This design is mainly aimed at a new small condensing coal-fired power plants, mainly installed a generator QF-25-type 2 and a generator QFQ-50-type 2, rated voltage is 10.5 KV, loop number is four which was ruled, the transmission distance respectively is: 25 km, 50 km and 75 km and 100 km. The main content of the design is given a raw material, and then I analyze the original material and choice main transformer, and design a relatively reasonable the main electrical wiring connection. Then I make the corresponding the calculation of short-circuit current according to the main electrical wiring, and chose and checkout if all kinds of electrical equipment is reasonable, at the same time, I protect the generator, transformer, transmission line accordingly and make the preliminary design of lightning protection for the whole power plant. Finally, I draw the corresponding main hookup accordingly to my own design.

Key words:  The main electrical wiring；electric equipment；relay protection；lightning protectio