三相異步電動機缺相分析及其保護電路的設計

電氣自動化論文編號:ZD733    論文字數:12534,頁數:30

目  錄
摘  要 I
Abstract II
第一章   緒論 1
第二章 三相異步電動機缺相運行分析 3
2.1 缺相情況概述 3
2.2 三相異步電動機缺相運行 3
2.3 缺相的各種原因 3
2.4判斷缺相的正確分析方法 4
2.5星型接法電動機的缺相分析 5
2.5.1 星型電動機起動前某電源線或繞組相斷開 5
2.5.2 星型電動機起動后某電源線或繞組相斷開 6
2.6三角形接法電動機的缺相分析 7
2.6.1起動前某繞組相斷開 7
2.6.2起動前某電源線斷開 7
2.6.3起動后某繞組相斷開 7
2.6.4起動后某電源線斷開 8
第三章  三相異步電動機缺相保護方案 11
3.1電流傳感型缺相保護 11
3.1.1根據熱繼電器的特有性能來保護電動機 11
3.1.2速飽和零序電流傳感器來保護電動機——三倍頻電壓 11
3.1.3負序電流過濾器保護法 12
3.1.4不平衡時零序電流的缺相保護法 14
3.1.5欠電流或過電流信號的缺相保護法 15
3.2電壓傳感型缺相保護 17
3.2.1簡單可靠的電機缺相保護電路——(聲光報警) 17
3.2.2采樣中性點電壓的缺相保護法 18
3.2.3可控硅的開關特性缺相保護法 19
3.2.4負序電壓過濾器的缺相保護法 20
3.2.5熔斷電壓控制的缺相保護電路 21
設計總結 23
參考文獻 25
致 謝 26

摘  要
 根據電動機缺相運行的各種情況,研究設計出符合生產要求的保護電路。我們知道,三相異步電動機三相繞組通入三相交流電時產生均衡的旋轉磁場。這是三相異步電動機運行的基本條件。所謂缺相,即三相供電電源中缺少一相(如三根相線中的任何一根斷開)或三相繞組中有任何一相斷開。發生上敘任何一種情況，都不具備三相異步電動機運行的基本條件,統稱為缺相運行。而在工礦企業生產運行中,異步電動機因缺相而燒毀的數量驚人。故本設計就缺相原因,斷相運行時的理論分析進行探討,以此作為尋求與評定合理的缺相保護措施的基礎, 在此次設計中,我們采用對稱分量法分析缺相運行,并分電動機起動前就缺相和電動機起動后發生缺相兩種情況進行分析。另外對于電動機的主要控制電路,缺相故障信號提取電路等等都加以分析,選擇。力求做到最經濟實用,安全有效，并進一步設計出適合實際生產的保護電路。
 
 關鍵詞：三相異步電動機；對稱分量法；保護電路；缺相
 
 Phase Motor Protection Circuit Analysis and Design
Abstract
 According to Phase motor running all the circumstances, research designs meet the production requirements of the protection circuit. We know that three-phase asynchronous motor three-phase winding access balanced three-phase alternating current generated when rotating magnetic field. This is the basic three-phase asynchronous motor running conditions. The so-called Phase that the lack of three-phase power supply in one phase (such as three-phase line in any one off) or three-phase windings have broken any one phase. Occurred on the Syrian any case, do not have the three-phase asynchronous motor running basic conditions, collectively known as the missing running. production operation in the industrial and mining enterprises, while the induction motor due to Phase alarming number burned. Therefore, this design causes the lack of phase, phase run-time analysis of the theory, Search and eva luation as a reasonable basis for phase protection measures, in this design, we use symmetry to analyze missing running, and the sub-motor starter motor before the start of Phase and Phase two cases occurring after the analysis. In addition to the main motor control circuit fault in the signal extraction circuit, etc. are analyzed and selected. Tried to be the most economical, safe and effective, and further design for the actual production of the protection circuit.

 Keywords:  Three-phase asynchronous motor；Symmetrical components；Protection circuit；Phase