变频器调速设计（毕业设计论文doc）.doc

摘要
三相交流异步电动机是工农业中最重要的拖动设备之一,因为其结构简单、维修容易而得到了广泛的应用,而随着社会进一步的发展,交流电机已经不仅仅局限于简单的恒速控制,在更多的现代工业生产中,很多设备需要根据不同的工作环境,要调节到一个特定的转速。从而对三相交流异步电动机的速度提出要求,希望能对电机运行速度进行调节,并能稳定运行。
电机交流变频调速技术是当今节电、改善工艺流程以提高产品质量和改善环境、推动技术进步的一种主要手段。三相交流异步电动机变频技术有调速时平滑性好,效率高;低速时,特性静关率高,相对稳定性好,调速范围大,精度高等特点和优点。变频器不但在传统的电力拖动系统中得到了广泛的应用,而且几乎已经扩展到了工业生产的所有领域,尤其在空调、洗衣机、电冰箱等家电产品中的应用。为了实现在恶劣的工作环境中对三相交流异步电动机进行远程控制,引入PLC(Programmable Logic Controller,可编程逻辑控制器)控制单元,实现了对变频调速系统的智能控制,使得该调速系统性能更加优越,满足了现代工业化生产的需要。
本次设计就是基于PLC的变频器调速系统,将现在应用最广泛的PLC和变频器综合起来实现电机的正反转,加减速以及快速制动等。
关键词:变频器;PLC;交流电机;调速
ABSTRACT
AC induction motor is one of the most important industrial and agricultural drag equipment. It has been widely used because of its simple structure and easy maintenance. With the further development of society, AC motor is not limited to simple constant speed control, in the more modern industrial production. Many devices need to be adjusted to a specific speed according to different working environments. For AC motor speed proposed requirements. The realization of operation speed regulation and stable operation.
AC variable frequency technology is energy saving, a major means to improve the process to improve product quality and improve the environment, promoting technological progress. AC motor frequency conversion technology are speed smooth and good, high efficiency; low speed characteristics, static clearance rate high, relatively good stability, wide speed range, high precision advantages and characteristics. Variable-frequency Drive has been widely used not only in traditional electric drive system, and almost has been extended to all areas of industrial production. Especially in air conditioners, washing machines, refrigerators and other appliances. In order to achieve the remote control in poor working conditions in the motor, the introduction of the PLC (Programmable Logic Controller ) control unit, realize the variable frequency speed regulation system of intelligent control, makes the speed regulation