前言城市中低壓配電網是電力系統的重要組成部分,是城市建設的重要基礎設施。為滿足城市建設、經濟發展和人民生活用電的需要,指導全國城市中低壓配電網改造工作,使之達到安全可靠、技術先進、經濟合理的要求,根據原能源部司局電供[1991]131號文和原能源部電力司提出的《關于加強城市中低壓配電網改造的若干意見》,由全國電力系統城市供電專業工作網負責,在廣泛征求意見的基礎上,總結了北京、上海、長沙、南京、沈陽、廣州、武漢、福州、重慶、昆明、烏魯木齊、遼陽、包頭供電局(電業局)城市中低壓配電網改造方面的經驗,由北京供電局具體起草了本技術導則。本標準由電力工業部安全監察及生產協調司提出并歸口。本標準由全國電力系統城市供電專業工作網、北京供電局起草。本標準主要起草人:寧岐、陳光華、關誠、伍秋熹、牛益民。
上傳時間: 2013-10-28
上傳用戶:水口鴻勝電器
高壓配電網的保護措施有:一、電網相間短路的電流保護。正常運行時輸電線路上流過負荷電流,母線電壓約為額定電壓。當輸電線路發生短路時,故障相電流增大。根據這一特征,可以構成反應故障時電流增大而動作的電流保護。對于輸電線路相間短路通常采用三段式電流保護即無時限電流速斷保護(電流I段),限時電流速斷保護(電流II段),和定時限過電流保護(電流III段)。其中電流I段、II段共同構成線跌的主保護。III段為后備保護。1、無時限電流速斷保護。在保證選擇性和可靠性的前提下,根據對繼電保護快速性的要求,原則上應裝設快速動作的保護裝置,使切除故障的時間盡可能短。反應電流增加,且不帶時限動作的電流保護稱為無時限電流速斷保護。在單側電源輻射形電網為切除線路故障,需在每條線跌電源側裝設斷路器和相應的保護。假設線路L1、L2分別裝有電流速斷保護1和保護2,當線路L1上發生短路時,希望保護1能瞬時動作。但從選擇要求出發,在下一條線路即L2首端K2點短路時,保護1能瞬時動作。但從選擇性要求出發,在下一條線路L2首端K2點短路時,保護1不應動作,而應由保護2動作切除故障,為使保護1在K2點短路時不起動,必須使它的動作電流大于K2點短路時的最大短路電流,又稱作按躲過一下條線路出口處短路的條件整定。
上傳時間: 2013-11-16
上傳用戶:zhengjian
基于單片機可編程低通濾波器設計
上傳時間: 2013-11-10
上傳用戶:xinzhch
《單片機基礎外設 九日通》
上傳時間: 2013-10-15
上傳用戶:墻角有棵樹
PIC單片機特殊指令助記符
上傳時間: 2013-10-22
上傳用戶:jhksyghr
摘要:“網絡通”是基于普通單片機的廉價以太網測控網關。它可以將具有RS-232、RS-485等接口的測控設備簡單而且直接地連接在以太網(因特網)上,利用豐富的現成的以太網資源,組成一系列以太網的分布式測控系統。關鍵詞:以太網分布式測控系統 以太網測控網關 網關 網絡通
上傳時間: 2014-12-27
上傳用戶:xg262122
PCI總線是Pentium主機最常見的總線,基于PCI總線形成的CompactPCI和PXI總線廣泛地應用在儀器和自動化領域。PCI適配卡的接口設計變得越來越重要。本文對PCI專用接口電路PCI9052的功能進行了研究與分析,并給出了一個應用實例設計。
上傳時間: 2013-11-02
上傳用戶:unmwq
PIC特殊指令助記符
上傳時間: 2014-12-27
上傳用戶:天空說我在
I/O 型單片機使用手冊 目錄 間接尋址寄存器 – IAR, IAR0, IAR1 .............................................35間接尋址指針 – MP, MP0, MP1 ......................................................35存儲區指針 – BP .........................................................................36累加器 – ACC...................................................................................37程序計數器低字節寄存器 – PCL....................................................37表格寄存器 – TBLP,TBHP,TBLH....................................................37看門狗定時寄存器 – WDTS............................................................38狀態寄存器 – STATUS.....................................................................38中斷控制寄存器 – INTC,INTC0,INTC1 .........................................39定時/計數寄存器...............................................................................39輸入/輸出端口和控制寄存器...........................................................40UART 寄存器 .USR,UCR1,UCR2,TXR/RXR,BRG.......................40輸入/輸出端口..........................................................................................41上拉電阻............................................................................................41PA 口的喚醒......................................................................................41輸入/輸出端口控制寄存器...............................................................41引腳共享功能....................................................................................42編程注意事項....................................................................................45定時/計數器..............................................................................................46配置定時/計數器輸入時鐘源...........................................................47定時/計數寄存器 – TMR, TMR0,TMR0L/TMR0H,TMR1L/TMR1H,TMR2.....................................................................49定時/計數控制寄存器 – TMRC,TMR0C,TMR1C,TMR2C............50定時器模式........................................................................................53事件計數器模式................................................................................53脈沖寬度測量模式............................................................................54可編程分頻器(PFD)和蜂鳴器的應用..............................................55預分頻器(Prescaler)...........................................................................56輸入/輸出接口...................................................................................56編程注意事項....................................................................................57定時/計數器應用范例.......................................................................57中斷............................................................................................................59中斷寄存器........................................................................................59中斷優先權........................................................................................62外部中斷............................................................................................63定時/計數器中斷...............................................................................64UART 中斷........................................................................................64編程注意事項....................................................................................65復位和初始化............................................................................................66復位....................................................................................................66目錄iii異步串行口——UART............................................................................74UART 特性..........................................................................................74UART 外部引腳..................................................................................74數據發送.............................................................................................75UART 狀態控制寄存器......................................................................75波特率發生器.....................................................................................79UART 設置與控制..............................................................................81UART 發送器......................................................................................83UART 接收器......................................................................................84接收錯誤處理.....................................................................................85接收中斷圖解.....................................................................................86地址檢測模式.....................................................................................86暫停模式下的UART 功能.................................................................87UART 應用范例.................................................................................87振蕩器........................................................................................................89系統時鐘配置....................................................................................89系統晶體/陶瓷振蕩器.......................................................................89系統電阻電容振蕩器........................................................................90內部系統電阻電容振蕩器................................................................90RTC 振蕩器........................................................................................91看門狗定時振蕩器............................................................................91暫停和喚醒................................................................................................92暫停.....................................................................................................92進入暫停.............................................................................................92靜態電流.............................................................................................92喚醒....................................................................................................92看門狗定時器............................................................................................94掩膜選項....................................................................................................96應用電路....................................................................................................97第二部份 程序語言.....................................................................99第二章 指令集介紹.................................................................................101指令集......................................................................................................101指令周期..........................................................................................101數據的傳送......................................................................................101算術運算..........................................................................................102邏輯和移位運算..............................................................................102分支和控制的轉換..........................................................................102位運算..............................................................................................102查表運算..........................................................................................103其它運算..........................................................................................103指令設定一覽表......................................................................................104慣例..................................................................................................104I/O 型單片機使用手冊iv第三章 指令定義.....................................................................................107第四章 匯編語言和編譯器.....................................................................121常用符號..................................................................................................121語句語法..................................................................................................122名稱..................................................................................................122操作項..............................................................................................122操作數項..........................................................................................122注解..................................................................................................122編譯偽指令..............................................................................................123條件編譯偽指令..............................................................................123文件控制偽指令..............................................................................124程序偽指令......................................................................................126數據定義偽指令..............................................................................130宏指令..............................................................................................132匯編語言指令..........................................................................................136名稱..................................................................................................136助記符..............................................................................................136操作數、運算子和表達式..............................................................136其它..........................................................................................................139前置引用..........................................................................................139局部標號..........................................................................................139匯編語言保留字..............................................................................140編譯器選項..............................................................................................141編譯列表文件格式..................................................................................141源程序列表......................................................................................141編譯總結..........................................................................................142其它..................................................................................................142第三部份 開發工具................................................................... 145第五章 單片機開發工具.........................................................................147HT-IDE 集成開發環境............................................................................147盛群單片機仿真器(HT-ICE) ..................................................................149HT-ICE 接口卡.................................................................................149OTP 燒寫器.....................................................................................149OTP 適配卡.....................................................................................149系統配置..................................................................................................150HT-ICE 接口卡設置........................................................................151安裝..........................................................................................................153系統要求..........................................................................................153硬件安裝..........................................................................................153軟件安裝..........................................................................................154目錄v第六章 快速開始.....................................................................................159步驟一:建立一個新項目..............................................................159步驟二:將源程序文件加到項目中..............................................159步驟三:編譯項目..........................................................................159步驟四:燒寫OTP 單片機.............................................................160步驟五:傳送程序與掩膜選項單至Holtek ..................................160附錄............................................................................................... 161附錄A 特性曲線圖...................................................................................163附錄B 封裝信息.......................................................................................173
上傳時間: 2013-10-18
上傳用戶:blacklee
本文研究的低壓配電測量裝置是整套用電側電能管理系統中的最重要的一個環節,主要用于電網在線運行的設備的遠方監視和控制的網絡,對低壓電網運行狀態進行實時監測,及時掌握低壓配電網運行的情況,適時根據供電需求的增長調整電網負荷,及時發現和定位電網故障,發現異常供電和異常線損,杜絕供電隱患。該裝置能提供簡潔的人機接口界面、在線保護測量、記錄實時時間、對于采集的參數能實現在線存儲和斷電保存等功能。
上傳時間: 2013-10-18
上傳用戶:jackgao