直流电机PWM控制实现打印.doc

直流电机PWM控制实现
摘要
本文介绍了一种基于单片机控制的PWM直流电机调速系统,系统以89C51单片机为核心,以小型直流电机为控制对象,实现双闭环PI控制。系统包括转速给定、转速显示、转速检测、电流检测、PWM脉宽信号产生电路以及直流电机驱动电路。从直流调速系统原理出发,逐步建立了双闭环直流PWM调速系统的数学模型,给出了该系统的详细设计思路、软硬件设计、电路结构和采用PI控制算法的控制程序流程。在芯片选择方面,以89C51为控制核心,分别采用了AD574电流模/数转换、8253转速M/T法测量、8279转速设定/显示、DAC1208/TL494PWM波形产生、LDM18200电机驱动等芯片与一些外围电路。该系统具有较好的控制精度,可以在中小功率直流电动机上广泛应用。
关键词单片机;直流电机;调速系统;PWM;双闭环控制
Abstract
A kind of PWM direct current motor speeding control system by this paper is introduced based on Single-puter this system, taking the single- puter89C51 as the core part and the small-type of DC motor as the control double closed-loop PI control is system consists of rotation setting,display and detection, current sensing, PWM pulse signals generator circuit and the DC drive with the theory of the DC timing system,this article has built up the maths model of the reversible DC-PWM timing system with a dual-converter and dual-closed-loop,Given the details of the system design, software and hardware design, circuit structure and control algorithms using the PI process control proce- dures. In the chip selection, to 89C51 for the control of the core,By using the AD574 current A/D converter, 8253 Speed M/T measurement, 8279 speed settings/Show, DAC1208/TL494PWM waveform generator, LDM18200 motor drive, such as chips and some external system has better control accuracy, in small and medium-sized power on the wider use of DC motor.
Key words single-puter;DC motor; adjustment speed system;PWM;double closed-loop control
目录
摘要 I
Abstract II
目录 III
第1章绪论 1
序言 1
直流调速系统发展概况 1
第2章直流脉宽调速系统的理论研究 2
直流电动机的调速方案 2
直流电机PWM调速原理 2
双闭环可逆直流PWM调速系统原理 4
转速、电流双闭环调速系统的组成 4
稳态结构图和静特性 5
双闭环脉宽调速系统的动态性能 6
第3章双闭环可逆直流PWM调速系统的硬件设计 9
单片机的选择 10
电流检测电路 13
AD574的工作原理 14
AD574与89C51单片机的接口电路 14
15
M/T法测速原理 15
转速测量硬件电路 17
转速设定/显示电路 17
8279可编程键盘、显示接口芯片 17