電壓無功補償綜合控制裝置

電子機電論文編號:JD084    包括大圖,字數:31854,頁數:79

目 錄
摘要........................................................... I
Abstract .......................................................II

第1章緒論......................................................1
1.1無功補償的定義與作用 ........................................1
1.2課題背景.....................................................2
1.3國內外研究現狀...............................................3
1.4本文研究的主要內容 ..........................................4
第2章無功補償原理及調節判據 ...................................5
2.1無功補償的原理...............................................5
2.1.1電壓損耗與電壓損失率的計算................................ 5
2.1.2并聯電容器補償.............................................7
2.2并聯補償電容器的配置原則 ...................................11
2.3調節判據的選擇..............................................11
第3章 主系統設計...............................................15
3.1主電路......................................................15
3.2電容器組投切及晶閘管過零電路比較 ...........................17
3.2.1電容器組投切方式..........................................17
3.2.2晶閘管電壓過零觸發電路 ...................................19
3.3器件的選型..................................................21
第4章 TSC控制裝置的硬件電路設計................................24
4.1電壓電流的轉換..............................................25
4.2數據采集電路................................................28
4.3單片機及其擴展電路 .........................................33
4.4鍵盤及顯示電路 .............................................39
4.5投切控制電路................................................42
第5章軟件設計 ................................................46
社會經濟效益分析...............................................50
結論.........................................................  51
致  謝 ....................................................... 52
參考文獻...................................................... 53
附錄1 ........................................................ 55
附錄2 ........................................................ 61
附錄3...................................................... .. 69

摘 要
無功補償的方法多種多樣，最常見的就是并聯電容器補償。低壓動態無功補償裝置是采用交流采樣的方法對三相電壓和電流分別采樣，每周期測出20個瞬時值，經AD574把模擬量轉換為12位數字量，由有效值計算公式算出每相電壓、電流和無功功率Q，利用電壓和無功構成的綜合判據通常規定了電壓和無功的上下限，并把電壓和無功平面分成9個區，根據電壓和無功的綜合控制方法，通過晶閘管控制電容器的投切對電壓和無功實行綜合調節，以保證電壓在合格范圍內，同時實現無功的基本平衡。。
本裝置對三相無功分別補償，采用晶閘管作為無觸點開關，利用過零比較器可實現對電容器組的無過渡過程的快速投切，避免了合閘時產生沖擊電流損壞電器元件。電容器組的投切方式采用編碼投切，三組電容器按容量比1：2：4即可組合成7個容量等級，投切控制方便，經濟效益顯著。
控制電路主要由交流采樣單元、外部擴展單元、顯示單元、控制單元等組成，硬件緊湊，編程容易，控制簡單。本裝置對電網參數實時檢測，對系統無功實行跟蹤補償。補償效果快速、準確、安全、易于控制，應用前景十分廣闊。

關鍵詞   無功補償    綜合控制    晶閘管開關

Abstract
    Reactive compensation variety of ways, the most common is the shunt capacitor compensation. LV dynamic reactive compensation devices is the use of sampling methods for three-phase voltage and current, respectively sampling, week period measured 20 instantaneous value, AD574 conversion from analog to digital 12. RMS calculated by the formula calculated for each phase voltage, current and reactive power Q, the use of voltage and reactive composition of the criteria usually provides the voltage and reactive power of the lower and upper limits and voltage and reactive plane divided into nine districts, according to the voltage and reactive power integrated control method, thyristor controlled by the switching capacitor pair of voltage and reactive power integrated regulate in order to ensure that qualified voltage range, Reactive while achieving the basic balance.
The device respectively compensation three-phase reactive, using thyristor as a non-contact switch, Comparing the use of zero for the capacitors can be realized without the group's rapid transition to the top, Closing avoid the shocks arising from the current damage to the electrical components. The capacitor switching is used for encoding all three groups capacitor capacity by more than 1 : 2 : 4 will be combined into seven levels of capacity, switching control convenience, significant economic benefits.
Control circuit mainly include the exchange of sampling unit, the external expansion unit, display units, the control unit and other components, compact hardware, Programming easy, simple control. The device to real-time detection of network parameters, the system implemented tracking reactive compensation. Compensation results fast, accurate, safe and easy to control, very broad application prospects.

Key  words  reactive compensation   comprehensive control   thyristor switches