摘 要:随着变频调速技术的发展与广泛的应用,对变频调速系统的控制精度也越来越高。目前。许多变频调速装置属于开环控制方式,不能满足较高精度的要求。为提高调速系统的精度,一般都需要进行闭环控制。被广泛应用的交流电机,由于其数学模型和运算较为复杂,其控制特性会受对象内部参数变化的影响,因而用固定的调节器去控制时,往往难以得到较理想的静动态特性[1]。采取可靠的PLC和变频器控制交流异步电机方法,把模糊控制算法引入到控制系统中,提高了系统的静动态特性。
本文结合异步电动机速度闭环控制,提出了一种基于PLC的模糊逻辑控制实现方法。首先对模糊控制变频调速系统进行总体设计,其次再进行PLC、变频器与上位机通信程序设计。在此基础上,论述模糊控制器的工作原理及其结构,用PLC编程实现了模糊控制器的设计。此设计系统将模糊控制与PLC相结合,有效的解决了传统的调节器超调大的缺点,提高了系统控制的精确度。结果表明,该系统能对电机转速实现精确控制,实用性强,具有很好的推广价值。6411
关键词:模糊控制;变频器;PLC
Intelligence control application in variable frequency speed regulation system
Abstract:With the increasing applications of variable frequency speed control technology,the accuracy of variable frequency speed control system generally require closed loop control.However,the Asynchronous motor’s models are more complex,and its control identity will be subject to the impact of changes in internal parameters,thus it is often difficult to obtain better conditions dynamic character by using fixed regulator to control. Hence a speed control system with PLC based on fuzzy control is provided.
In this paper,a fuzzy control method applied to the system with PLC is presented and the fuzzy control algorithm to be realized with PLC is given according to conditions of variable frequency speed control system. We firstly research into the design of variable frequency speed control system ,and then the communication between PLC and computer and the communication between inverter and PLC are discussed .Furthermore ,it pays more attention to introduce the comprising of fuzzy
controller and the methods how to realize. The system overcomes weakness of traditional regulator,it has advantages increases the accuracy of the system.The results show the system has good performance and applicable value.
Key words: fuzzy control;inverter;PLC
目录
1 引言1
1.1 国内外变频技术的发展现状.1
1.1.1 国内变频调速技术的发展概况1
1.1.2 国外变频调速技术的发展概况1
1.2 模糊控制理论概况.2
1.3 可编程控制器技术的发展及应用.3
1.4 选题的依据.6
2 模糊控制变频调速系统的总体设计7
2.1 变频调速系统模糊控制策略.7
2.2 变频调速系统组成.7
3 PLC与变频器、上位机通信程序设计.10
3.1 PLC与上位机通信.10
3.1.1 概述10
3.1.2 通信原理.10
3.1.3 变频器与PLC通信11
3.1.4 通信参数设置11
3.1.5 建立计算机与PLC的通信连接.12
3.2 变频器与上位机通信13
3.2.1 系统硬件组成与连结13
3.2.2 变频器参数的设置15
3.2.3 PLC与变频器之间的通信16
3.2.4 软件编程18
4 模糊控制原理及控制器的设计实现.20
4.1 模糊控制的原理20
4.1.1 模糊控制的基本思想20
4.1.2 模糊控制器的基本结构20
4.1.3 模糊控制的特点22 PLC模糊控制变频调速系统总体设计+源程序:http://www.751com.cn/zidonghua/lunwen_3943.html