【正文】 I 摘要 作為電網(wǎng)中重要的設(shè)備之一，電力變壓器的正常工作與否直接影響電網(wǎng)的安全穩(wěn)定運(yùn)行。本論文首先闡述了電力變壓器在線監(jiān)測系統(tǒng)的研究目的和意義、國內(nèi)外研究動態(tài)和發(fā)展趨勢，然后進(jìn)行了深入地分析。 本文其次介紹了鐵心接地電流、電壓、溫度在線監(jiān)測系統(tǒng)。該系統(tǒng)能夠?qū)崿F(xiàn)對變壓器鐵心接地電流、電壓、溫度的實(shí)時(shí)或定時(shí)監(jiān)測和歷史數(shù)據(jù)的存儲，并在接地線電流、電壓、溫度超過國家標(biāo)準(zhǔn)后能夠發(fā)出信號和實(shí)現(xiàn)限流電阻的自動投切，將接地電流、電壓、溫度限制在規(guī)程要求的范圍之內(nèi)。變壓器鐵心電流、電壓、溫度的在線監(jiān)測，必須確保采集到的 信號真實(shí)可靠，同時(shí)應(yīng)保證監(jiān)測裝置最小限度的改變變壓器的運(yùn)行接線狀態(tài)。作為一種工作在電流大范圍內(nèi)變化的設(shè)備，必須具備較好的量程自動轉(zhuǎn)換及保護(hù)電路。在變壓器所處的惡劣的電磁環(huán)境中，設(shè)備要能夠穩(wěn)定可靠的工作，抗電磁干擾是難點(diǎn)。作為便攜式設(shè)備，應(yīng)保證信號所測得的數(shù)據(jù)能夠方便的上傳給控制人員，通訊方式最好采用無線方式。盡可能實(shí)現(xiàn)多點(diǎn)接地故障的自動處理。 關(guān)鍵字：電力變壓器；鐵芯接地電流；電壓；變壓器油溫；在線監(jiān)測 II Abstract As one of the important equipment in the power grid, power transformer works or not directly affect the safe and stable operation of power grids. This paper first provides power transformer online monitoring system of purpose and meaning, research and development trends at home and abroad, and then make a thorough analysis. This second article describes core earth currents, voltages, temperature online monitoring system. The system can be realized on earth current, voltage and temperature of transformer core storage or regularly monitored in real time and historical data, And on the ground, current, voltage, temperature exceeds the national standards will be able to send a signal and automatic switching of current limiting resistor, to limit the earth current, voltage and temperature within the scope of the code requirements. Current, voltage and temperature on line monitoring of transformer core, you must ensure that collected signals are true and correct, should ensure that monitoring devices at the same time minimise change the running of transformer connection state. As a change in the current scope of work equipment must have a good Automatic Range conversion and protection circuit. In adverse electromagic environment of the transformers, stable and reliable equipment to be able to work, EMI is difficult. As a portable device, make sure the signal measured it easy to upload data to the control of personnel, means of munication the best use of wireless processing for multi point earthing fault as much as possible. Key words: power transformer。 Core earth current。 Voltage。 Transformer oil temperature。 Online monitoring 目錄 0 引言 ................................................................................................................................... 1 1 緒論 ................................................................................................................................... 2 目的和意義 .................................................................................................................. 2 國內(nèi)外發(fā)展現(xiàn)狀 ......................................................................................................... 3 變壓器原理 .................................................................................................................. 4 2 10kV 電力變壓器狀態(tài)參量監(jiān)測系統(tǒng)總體設(shè)計(jì)方案 .......................................... 5 在線監(jiān)測系統(tǒng)的組成 ............................................................................................... 5 功能設(shè)計(jì)方案 ............................................................................................................. 6 3 10kV 電力變壓器狀態(tài)參量監(jiān)測系統(tǒng)硬件電路設(shè)計(jì) .......................................... 8 電流信號的提取部分 ............................................................................................... 9 電壓電流互感器原理和使用 ................................................................................. 9 ...........................................................................................10 ........................................................................................... 11 電壓互感器的選擇和采樣電路設(shè)計(jì) .................................................................12 JDZW10型電壓互感器的性能和特性概述 ....................................... 12 ....................................................... 13 電流互感器的選擇和電路設(shè)計(jì) ...........................................................................14 LBZ10 型電流互感器技術(shù)指標(biāo) ......................................................................14 ..........................................................15 DS18B20 溫度檢測系統(tǒng)設(shè)計(jì) ................................................................................16 限流電阻單元 ........................................................................................................... 18 ADC0832 采樣電路設(shè)計(jì) ........................................................................................ 19 外部引腳及其說明 ............................................................................................... 20 ADC0832 的控制原理 .................................................................... 20 ADC0832典型應(yīng)用 .............................................................................................. 22 LCD1602 液晶顯示部分 ........................................................................................ 24 抗電磁干擾 ................................................................................................................. 26 單片機(jī)最小系統(tǒng)設(shè)計(jì) ............................................................................................ 26 ................................................................................................................ 29 STC89C52的并 行 I/O口詳細(xì)說明 .............................................................. 30 鍵盤操作部分 .......................................................................................................... 31 ......................................................................................................................... 31 信號傳輸部分 .......................................................................................................... 33 SIM300C 模塊 ....................................................................................... 33 SIM 卡接口 ......................................................................................................