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繼電保護外文翻譯-其他專業(yè)-展示頁

2025-01-31 02:57本頁面
  

【正文】 院研制的微機線路保護裝置也于 1991 年通過鑒定。至此,不同原理、不同機型的微機線路和主設(shè)備保護各具特色,為電力系統(tǒng)提供了一批新一代性能優(yōu)良、功能齊全、工作可靠的繼電保護裝置??梢哉f從 90年代開始我國繼電保護技術(shù)已進入了微機保護的時代。 隨著計算機硬件的迅猛發(fā)展,微機保護硬件也在不斷發(fā)展。華中理工大學(xué)研制的微機保護也是從 8位 cpu,發(fā)展到以工控機核心部分為基 礎(chǔ)的 32 位微機保護。東南大學(xué)研制的微機主設(shè)備保護的硬件也經(jīng)過了多次改進和提高。采用 32位微機芯片并非只著眼于精度,因為精度受 a/d轉(zhuǎn)換器分辨率的限 制,超過 16位時在轉(zhuǎn)換速度和成本方面都是難以接受的;更重要的是 32位微機芯片具有很高的集成度,很高的工作頻率和計算速度,很大的尋址空間,豐富的指令系統(tǒng)和較多的輸入輸出口。 電力系統(tǒng)對微機保護的要求不斷提高,除了保護的基本功能外,還應(yīng)具有大容量故障信息和數(shù)據(jù)的長期存放空間,快速的數(shù)據(jù)處理功能,強大的通信能力,與其它保護、控制裝置和調(diào)度聯(lián)網(wǎng)以共享全系統(tǒng)數(shù)據(jù)、信 息和網(wǎng)絡(luò)資源的能力,高級語言編程等。在計算機保護發(fā)展初期,曾設(shè)想過用一臺小型計算機作成繼電保護裝置?,F(xiàn)在,同微機保護裝置大小相似的工控機的功能、速度、存儲容量大大超過了當年的小型機,因此,用成套工控機作成繼電保護的時機已經(jīng)成熟,這將是微機保護的發(fā)展方向之一。這種裝置的優(yōu)點有: (1)具有 486pc機的全部功能,能滿足對當 前和未來微機保護的各種功能要求。 (3)采用 std總線或 pc總線,硬件模塊化,對于不同的保護可任意選用不同模塊,配置靈活、容易擴展。但對如何更好地滿足電力系統(tǒng)要求,如何進一步提高繼電保護的可靠性,如何取得更大的經(jīng)濟效益和社會效益,尚須進行具體深入的研究。它深刻影響著各個工業(yè)領(lǐng)域,也為各個工業(yè)領(lǐng)域提供了強有力的通信手段。繼電保護的作用也只限于切除故障元件,縮小事故影響范圍。國外早已提出過系統(tǒng)保護的概念,這在當時主要指安全自動裝置。這就要求每個保護單元都能共享全系統(tǒng)的運行和故障信息的數(shù)據(jù),各個保護單元與重合 閘裝置在分析這些信息和數(shù)據(jù)的基礎(chǔ)上協(xié)調(diào)動作,確保系統(tǒng)的安全穩(wěn)定運行。這在當前的技術(shù)條件下是完全可能的。繼電保護裝置能夠得到的系統(tǒng)故障信息愈多,則對故障性質(zhì)、故障位置的判斷和故障距離的檢測愈準確。 對于某些保護裝置實現(xiàn)計算機聯(lián)網(wǎng),也能提高保護的可靠性。其原理是將傳統(tǒng)的集中式母線保護分散成若干個 (與被保護母線的回路數(shù)相同 )母線保護單元,分散裝設(shè)在各回路保護屏上,各保護單元用計算機網(wǎng)絡(luò)聯(lián)接起來,每個保護單元只輸入本回路的電流量,將其轉(zhuǎn)換成數(shù)字量后,通過計算機網(wǎng)絡(luò)傳送給其它所有回路的保護單元,各保護單元根據(jù)本回路的電流量和從計 算機網(wǎng)絡(luò)上獲得的其它所有回路的電流量,進行母線差動保護的計算,如果計算結(jié)果證明是母線內(nèi)部故障則只跳開本回路斷路器,將故障的母線隔離。這種用計算機網(wǎng)絡(luò)實現(xiàn)的分布式母線保護原理,比傳統(tǒng)的集中式母線保護原理有較高的可靠性。 由上述可知,微機保護裝置網(wǎng)絡(luò)化可大大提高保護性能和可靠性,這是微機保護發(fā)展的必然趨勢。它可從網(wǎng)上獲取電力系統(tǒng)運行和故障的任何信息和數(shù)據(jù),也可將它所獲得的被保護元件的任何信息和數(shù)據(jù)傳送給網(wǎng)絡(luò)控制中心或任一終端。 4 目前,為了測量、保護和控制的需要,室外變電 站的所有設(shè)備,如變壓器、線路等的二次電壓、電流都必須用控制電纜引到主控室。但是如果將上述的保護、控制、測量、數(shù)據(jù)通信一體化的計算機裝置,就地安裝在室外變電站的被保護設(shè)備旁,將被保護設(shè)備的電壓、電流量在此裝置內(nèi)轉(zhuǎn)換成數(shù)字量后,通過計算機網(wǎng)絡(luò)送到主控室,則可免除大量的控制電纜?,F(xiàn)在光電流互感器 (ota)和光電壓互感器 (otv)已在研究試驗階段,將來必然在電力系統(tǒng)中得到應(yīng)用。 ota 和 otv 的光信號輸入到此一體化裝置中并轉(zhuǎn)換成電信號后,一方面用作保護的計算判斷;另一方面作為測量量,通過網(wǎng)絡(luò)送到主控室。 1992 年天津大學(xué)提出了保護、控制、測量、通信一體化問題,并研制了以 tms320c25 數(shù)字信號處理器 (dsp)為基礎(chǔ)的一個保護、控制、測量、數(shù)據(jù)通信一體化裝置。神經(jīng)網(wǎng)絡(luò)是一種非線性映射的方法,很多難以列出方程式或難以求解的復(fù)雜的非線性問題,應(yīng)用神經(jīng)網(wǎng)絡(luò)方法則可迎刃而解。其它如遺傳算法、進化規(guī)劃等也都有其獨特的求解復(fù)雜問題的能力。天津大學(xué)從 1996 年起進行神經(jīng)網(wǎng)絡(luò)式繼電保護的研究,已取得初步成果。 三 總結(jié) 建國以來,我國電力系統(tǒng)繼電保護技術(shù)經(jīng)歷了 4 個時代。國內(nèi)外繼電保護技術(shù)發(fā)展的趨勢為:計算機化,網(wǎng)絡(luò)化,保護、控制、測量、數(shù)據(jù)通信一體化和人工智能化,這對繼電保護工作者提出了艱巨的任務(wù),也開辟了活動的廣闊天地。s, our country engineers and technicians creatively absorption, the digestion, have grasped the overseas advanced relay protection equipment performance and the movement technology , pleted to have the deep relay protection theory attainments and the rich movement experience relay protection technical team, and grew the instruction function to the national relay protection technical team39。s. This is a time which the mechanical and electrical relay protection prospers, was our country relay protection technology development has laid the solidfoundation. From the end of the 5039。s to the 8039。s, started based on the integration operational amplifier integrated circuit protection to study. Has formed the plete series to at the end of 8039。s still were in the dominant position, this was the integrated circuit protection time. The integrated electricity road work frequency conversion quantity direction develops which in this aspect Nanjing electric power automation research institute high frequency protected the vital role , the Tianjin University and the Nanjing electric power automation plant cooperation development integrated circuit phase voltage pensated the type direction high frequency protection also moves in multi strip 220kv and on the 500kv line. Our country namely started the puter relay protection research from the end of the 7039。s function. Huazhong University of Science and Technology, southeast the university, the North China electric power institute, the Xian Jiaotong University, the Tianjin University, Shanghai Jiaotong University, the Chongqing University and the Nanjing electric power automation research institute one after another has all developed the different principle, the different pattern microputer protective device. In 1984 the original North China electric power institute developed the transmission line microputer protective device first through the appraisal, and in the system the find application, had opened in our country relay protection history the new page, protected the promotion for the microputer to pave the way. In the host equipment protection aspect, the generator which southeast the university and Huazhong University of Science and Technology develops loses magism protection, the generator protection and the generator?Bank of transformers protection also one after another in 1989, in 1994 through appraisal, investment movement. The Nanjing electric power automation research institute develops microputer line protective device also in 1991 through appraisal. The Tianjin University and the Nanjing electric power automation plant cooperation development microputer phase voltage pensated the type direction high frequency protection, the Xian Jiaotong University and the Xu Chang relay factory cooperation development positive sequence breakdown ponent direction high frequency protection also one after another in 1993, in 1996 through the appraisal. Heres, the different principle, the different type microcomputer line and the host equipment protect unique, provided one batch of new generation of performance for the electrical power system fine, the function has been plete, the work reliable relay protection installment. Along with the microputer protective device research, in
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