三相异步电动机缺相分析及其保护电路的设计

电气自动化论文编号:ZD733    论文字数:12534,页数:30

目  录
摘  要 I
Abstract II
第一章   绪论 1
第二章 三相异步电动机缺相运行分析 3
2.1 缺相情况概述 3
2.2 三相异步电动机缺相运行 3
2.3 缺相的各种原因 3
2.4判断缺相的正确分析方法 4
2.5星型接法电动机的缺相分析 5
2.5.1 星型电动机起动前某电源线或绕组相断开 5
2.5.2 星型电动机起动后某电源线或绕组相断开 6
2.6三角形接法电动机的缺相分析 7
2.6.1起动前某绕组相断开 7
2.6.2起动前某电源线断开 7
2.6.3起动后某绕组相断开 7
2.6.4起动后某电源线断开 8
第三章  三相异步电动机缺相保护方案 11
3.1电流传感型缺相保护 11
3.1.1根据热继电器的特有性能来保护电动机 11
3.1.2速饱和零序电流传感器来保护电动机——三倍频电压 11
3.1.3负序电流过滤器保护法 12
3.1.4不平衡时零序电流的缺相保护法 14
3.1.5欠电流或过电流信号的缺相保护法 15
3.2电压传感型缺相保护 17
3.2.1简单可靠的电机缺相保护电路——(声光报警) 17
3.2.2采样中性点电压的缺相保护法 18
3.2.3可控硅的开关特性缺相保护法 19
3.2.4负序电压过滤器的缺相保护法 20
3.2.5熔断电压控制的缺相保护电路 21
设计总结 23
参考文献 25
致 谢 26

摘  要
 根据电动机缺相运行的各种情况,研究设计出符合生产要求的保护电路。我们知道,三相异步电动机三相绕组通入三相交流电时产生均衡的旋转磁场。这是三相异步电动机运行的基本条件。所谓缺相,即三相供电电源中缺少一相(如三根相线中的任何一根断开)或三相绕组中有任何一相断开。发生上叙任何一种情况，都不具备三相异步电动机运行的基本条件,统称为缺相运行。而在工矿企业生产运行中,异步电动机因缺相而烧毁的数量惊人。故本设计就缺相原因,断相运行时的理论分析进行探讨,以此作为寻求与评定合理的缺相保护措施的基础, 在此次设计中,我们采用对称分量法分析缺相运行,并分电动机起动前就缺相和电动机起动后发生缺相两种情况进行分析。另外对于电动机的主要控制电路,缺相故障信号提取电路等等都加以分析,选择。力求做到最经济实用,安全有效，并进一步设计出适合实际生产的保护电路。
 
 关键词：三相异步电动机；对称分量法；保护电路；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