《(徐爱荣)交流电动机减压软启动系统的设计_定稿.pdf》由会员分享，可在线阅读，更多相关《(徐爱荣)交流电动机减压软启动系统的设计_定稿.pdf（14页珍藏版）》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、浙江大学远程教育学院本 科 生 毕 业 论 文 学习中心洛阳姓名徐爱荣学号 D20505320011 指导教师屈稳太2007 年12 月4 日I/14 交流电动机减压软启动系统的设计摘 要从交流电机发展至今，三相交流异步电动机得到了广泛的应用，其性能和功率在不断的提高，电压从低压发展到高压。随着三相交流异步电动机功率的提高，其启动过程也出现诸多弊端，如三相交流异步电动机直接启动时，启动电流一般可达5-8 倍的额定电流，较大的启动电流流过电机绕组，产生大量热量，加速绝缘老化，影响电机寿命。在三相交流异步电动机不宜采用直接启动的时候，可考虑采用电动机降压启动或其它启动方式。三相晶闸管调压软启动是近
2、年来发展的新技术，采用反并联接线的晶闸管接在电动机的三相绕组上，在电动机启动过程中通过控制晶闸管导通角的大小，使电动机的启动电流可根据工作要求设定的规律变化。本文详细分析了调压软启动的原理并且建立了相应的仿真模型并对其进行了验证。关键字：直接启动启动电流软启动仿真文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码
3、:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4
4、HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 Z
5、S10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档
6、编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V
7、4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7
8、 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3
9、II/14 目 录一交流电动机传统启动技术1一）三相交流异步电动机的直接启动及其存在的问题11三相交流异步电动机的简化数学模型12直接启动所存在的问题2二）三相交流异步电动机的传统启动技术及其存在的问题2二交流电动机降压软启动技术3一）降压软启动器调节原理3二）降压软启动器的主电路结构4三）晶闸管调压原理4四）降压软启动的启动方式及其控制策略51限流软启动 52电压斜坡启动53转矩控制启动54转矩加突跳控制启动55停车方式 6三系统仿真及结果6一）Matlab/Simulink 工具简介 6二）异步电动机直接启动仿真6三）异步电动机降压软启动仿真71功能模块设计82仿真实验 9四毕业设计小结1
10、0五致谢 10参考文献 11文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S
11、3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7
12、R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P
13、1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H
14、2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2
15、E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M
16、4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S31/14 交流电动机减压软启动系统的设计一交流电动机传统启动技术从交流电机发展至今，三相交流异步电动机得到了广泛的应用，其性能和功率也不断的提高，电压也从低压发展到高压。随着三相交流异步电动机功率的提高，其启动过程也出现诸多弊端。在本章
17、中我们将对电机的启动问题进行简要分析和论述。一）三相交流异步电动机的直接启动及其存在的问题1三相交流异步电动机的简化数学模型为了研究异步电动机的启动和制动时的电压、电流、转矩等变量的关系，要先从三相异步电动机的运行状态和生产机械的负载特性出发。异步电动机的简化T型等效电路如图 1所示。其中、分别为定子的电阻和漏抗，、分别为折算后转子的电阻和漏抗，、分别为励磁电阻和励磁电抗，s为转差率。图1 异步电动机简化 T型等值电路由异步电动机简化等值电路可以求出三相异步电动机的转子电流：因为电机启动时，转子转速n=0，转差 s=1，此时的启动电流为：由上式可知，电机启动电流和电压成正比。由异步电动机的功率
18、平衡及转矩平衡关系可知，异步电动机的电磁转矩为：UI1jXmjX1RmR2jX2RS文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7
19、R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P
20、1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H
21、2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2
22、E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M
23、4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W
24、5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S32/14 式中：为旋转磁场的同步角速度将代入T中可得：由上式可知，当频率不变时，同步角速度及电机参数为常数，电磁转矩T是定子电压和转差率 s的函数。在电动机启动瞬间，s=1，则启动
25、转矩为：由此可知，在电机参数一定的情况下，启动转矩只和有关，两者为平方的关系。综上所述，当电源的频率和电动机参数都不变的情况下，启动转矩和成平方关系，启动电流和成正比，即在降低启动电压的情况下，启动电流和启动转矩都相应降低。因此，可以通过控制定子电压对启动转矩和启动电流进行控制，这即是大部分启动方式所采用的理论依据。2直接启动所存在的问题如果全电压直接启动，由1 中所分析的结论可知，启动转矩较大，而冲击电流也很大。我们首先来看一下较大的启动电流对电动机本身的影响。对于频繁启动的异步电动机，频繁出现短时大电流会使电动机内部过热，会对电动机产生不良影响。再来看启动电流对供电变压器的影响。配电变压器
26、的容量是按照其供电的负载总容量来设计的，正常运行条件下由于电流不超过额定电流，其输出的电压比较稳定。三相异步电动机启动时，如变压器相对容量不是很大，电动机短时较大的启动电流会使变压器输出的电压短时下降幅度很大，超出正常允许的范围，这时就会产生如下影响：错误!启动电动机本身由于电压太低，使启动转矩下降很大，当负载较重时，有可能启动不了；错误!会对同一变压器供电的其他负载产生不良影响，如电灯变暗，重载电动机停转等。由以上分析可知，异步电动机直接启动有其突出的缺陷，所以对容量较大的电动机都采用一些特殊的技术来进行启动。二）三相交流异步电动机的传统启动技术及其存在的问题在三相交流异步电动机不宜采用直接
27、启动的时候，可考虑采用电动机降压启动。传统的电动机降压启动方式有定子串电阻电抗器降压启动、转子串电阻降压启动、Y一降压启动、自偶变压器降压启动等。表1对这几种启动方式进行了比较。由表1可以看出，这些启动方式虽然在一定程度上解决了启动电流过大的问题，但是都是采取的有级调速方式；多数存在二次甚至多次冲击；同时启动设备带载切文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4
28、HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 Z
29、S10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档
30、编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V
31、4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7
32、 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3
33、文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R
34、3V4 HH7G3M4P1X7 ZS10R1W5H2S33/14 换容易拉弧损坏，设备维护量大等问题。随着电力电子技术的发展，一种新的启动技术软启动以其优良的启动、保护性能得到了广泛的关注。表1 异步电动机传统启动方式启动方式启动电流启动转矩优点缺点应用场合以直接启动为 1 直接启动1 1 启动设备简单启动冲击电流大，冲击力矩大中小功率电动机轻载或空载启动定子串电阻启动启动设备简单有级调速、启动转矩小适用于空载或轻载启动Y一启动1/3 1/3 启动设备简单，可频繁启动有极、有二次冲击正常运行为接法，空载或轻载启动自藕变压器降压启动启动转矩较大有极、设备体积大、不能频繁启动、多次冲击较大容量电机
35、、较大负载不频繁启动二交流电动机降压软启动技术降压软启动是近年来发展的新技术，采用反并联接线的晶闸管接在电动机的三相绕组上，在电动机启动过程中通过控制晶闸管导通角的大小，使电动机的启动电流可根据工作要求设定的规律变化。这样，电动机的启动电流大小、启动方式均可以任意调节和选择，可使电动机根据继电器保护特性而处于最佳的启动过程。一）降压软启动器调节原理利用交流电机的电压特性曲线来控制交流电机的启动，是电子软启动器的主要控图2 电子软启动系统框图制思想。采用三对反并联的晶闸管串联于电动机的三相供电电路上，利用晶闸管的电子开关特性，通过控制其触发脉冲、触发角的大小来改变晶闸管的开通时间，从而改变电动机
36、定子输入电压，以控制电动机的软启动过程。当电动机启动完成后，MU、V、W电压检测驱动电路电流检测控制单元指令和显示R、S、T文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10
37、R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:
38、CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 H
39、H7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS
40、10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编
41、码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4
42、 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S34/14 即端电压升至额定电压时，三相旁路接触器K吸合，使电动机直接并网运行。启动时，晶闸管的导通角从 0开始上升，逐渐增大，电动机的端电压
43、也从零开始上升，直至达到满足启动转矩要求，保证启动成功。电子软启动器的基本电路框图如图2所示。二）降压软启动器的主电路结构降压软启动器的电路原理如图3所示。在电机定子三相进线电路上串联六个反并联晶闸管 或三个双向晶闸管），可控制电压的双向通断。通过改变晶闸管的导通角来改变加到定子端的电压。由电机转矩和定子端电压的关系以及定子电流和定子端电压的关系可知，改变电压的有效值，即可改变交流电机启动时的冲击电流和转矩。图 3 晶闸管调压软启动主电路示意图三）晶闸管调压原理在工频电源和负载之间接入晶闸管调压器，就可以改变负载端的电压。用晶闸管调压的方法有两种：一种是相控调压，另一种是斩波调压，即用双向晶闸
44、管作为静止接触器，交替的接通与切断几个周波的电源电压，但是斩波调压用在异步电动机定子上，通断交替的频率不能太低。否则一方面会引起电动机转速的波动，另一方面每次接通电流相当于一次异步电动机重合闸的过程。当电源断开时，电动机气隙中的磁场将由转子中的瞬态电流来维持，并随转子而旋转，气隙磁场在定子绕组中感应的的电势频率将有所变化，当断流时间间隔稍长时，这个旋转磁场在定子中感应的电势和重新接通时的电源电压在相位上可能会有相当大的差别，这样就会出现较大的冲击电流。可能危及晶闸管的安全。如通断交替频率较高，每次通断时间间隔中交流电周波数较少，采用整周波斩波控制方法可能调速不够平滑，所以在异步电动机的调压控制
45、中多用相控技术。由于异步电动机是感性负载，所以当晶闸管调压时，只有当移相角大于感性负载的功率因数角时，才能起到调压作用，因为当时，电流导通的时间将始终为，其情况与时一样，相控不起任何作用，因此的下限取为额定运行时的值，而上限取。在调压时，负载上所得到的电压与电流波形在根据触发角的不同而改变，单相晶闸管电路的电压输出波形如图4所示，其中为触发角，为续流角，为导通角，由图 4可知，角决定了晶闸管的输出电压，故改变角的大小就可以调节电机的输入电压，并且有：。可见电机的输入电压与触发角和续流角都有关系。MUVW文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:
46、CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 H
47、H7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS
48、10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编
49、码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4
50、 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7 ZS10R1W5H2S3文档编码:CK2W2E7R3V4 HH7G3M4P1X7