42极双速异步电动机运行控制.doc

白城职业技术学院毕业设计说明书 4|2极双速异步电动机运行控制 学生姓名： 专业班级： 电气自动化 指导教师： 职 称： 教授 起止日期： 2011.3.5-2011.6.20 白 城 职 业 技 术 学 院  摘 要 本文首先分析了三相异步电动机的工作原理， 然后分析了三相异步电动机的星形” “三角形启动。所谓星-三角启动 即工作时通过改变电机的接线方式而改变起动电压，从而降低启动电流。 本设计用于控制电机定子绕组由“星形”至“三角形”的换接启动、运行及停止。采用星-三角启动方式时，电流特性很好，适用于无载或者轻载起动的场合。 同任何别的降压启动方式相比，其结构最简单，价格也最便宜。除此之外，星三角启动方式还有一个优点，即当负载较轻时，可以让电动机在星形接法下运行。 此时，额定转矩与负载可以匹配，这样能使电动机的效率有所提高。 本设计主要介绍了双速异步电动机的变极原理、绕组排列、绕组接法、以及双速电动机的， 关键词：，星-三角启动双速变极调速电动机Abstract 4\2Double Speed Asynchronous Motor This paper firstly analyzes the three-phase asynchronous motors basic structure and operating principle of three-phase asynchronous motor, and then the Star triangle start working principle. The so-called star delta starting that work by changing the electrical wiring mode and change the start voltage, thereby reducing starting current. This design is used to control the motor stator winding consists of a Star to triangular transfer start, operation and stop. The star delta starting mode, current characteristics of good, applicable to the no load or light load. As any other reduced voltage starting means photograph is compared, its structure simple, the price is the cheapest. In addition, the star delta starting mode still has an advantage, namely when the load is light, can make motor run in star-shaped connection method. At this time, rated torque and the load can be matched, which can make the motor efficiency improvement. This paper introduces the design of the 4|2pole double speed asynchronous motor pole-changing principle, winding arrangement, winding and double speed motor, low speed operation control, achieve triangle speed, Star high speed operation Key words: high and low speed operation, star delta starting, two-speed pole-changing adjustable-speed motor 目 录 摘 要 I Abstract II 第一章 绪论 1 第二章4|2极异步电动机的运行设计 2 2.1技术要求 2 2.2各元器件的选择 2 2.2.1熔断器(FU)的选择 2 2.2.2接触器（KM1，KM2，KM3）的选择 2 2.2.3热继电器（FR）的选择 2 2.2.4时间继电器（ＫＴ）的选择 3 2.