基于AT89C51单片机控制的双闭环直流调速系统设计毕业设计论文（可编辑）.doc

基于AT89C51单片机控制的双闭环直流调速系统设计毕业设计论文 Abstract With the progress of the times and the development of science and technology, motor speed control system in the industrial and agricultural production, transportation and daily life plays an increasingly important role, therefore, the study of motor speed has a positive meaning. Long-term since, the DC motor is widely used in the control system, and has been in control field to dominate The design is based on the single chip microcomputer control of PWM DC motor speed control system, the system uses STC89C51 single chip microcomputer as the core, with 130small DC motor as control object, with L298N H bridge driver chip to realize the motor speed feedback control. Regulation of the PWM duty cycle to control the motor voltage at both ends, so as to achieve the purpose of speed. With 4*4 keyboard input control signal and parameters, and in 12864LED real-time display input parameters and dynamic speed. System hardware design part comprises a key module, motor drive module, STC89C51 singlechip system, photoelectric door gun module, protection circuit, power supply and a DC motor. System software includes keyboard control program design, program design, main control program design. The entire system to achieve the single-chip microcomputer to control the motor start and brake, reverse, speed regulating effect. Keywords :STC89C51 single chip microcomputer;DC motor;PWM;Duty ratio 目 录 摘 要 I Abstract II 1 引言 1 1.1 直流调速系统概况 1 1.2 设计目的和意义 2 1.3 国内外发展现状 3 1.4 设计要求和内容 3 2 直流调速原理分析与方案确定 4 2.1 直流PWM调速系统原理分析 4 2.2 方案论证和选择 6 3 系统硬件设计 10 3.1 按键控制模块 10 3.2 电动机驱动模块 11 3.4 STC89C51单片机系统 16 3.5 光电门测速模块 17 3.6 保护电路 18 3.7 供电电源 18 3.8 直流电动机的说明 18 3.9 系统总体设计电路图 19 4 系统软件设计 21 4.1 键盘控制程序设计 21 4.2 显示程序设计 23 4.3 主控程序设计 25 5 实物的直流调速实现与调试 29 结 论 33 参考文献 34 致 谢 35 1 引言 1.1 直流调速系统概况 现代工业的电力拖动一般都要求局部或全部的自动化,因此必然要与各种控制元件组成的自动控制系统联系起来,而电力拖动则可视为自动化电力拖动系统的简称。在这一系统中可对生产机械进行自动控制。 随着近代电力电子技术和计算机技术的发展以及现代控制理论的应用,自动化电力拖动正朝着计算机控制的生产过程自动化的方向迈进。以达到高速、优质、高效率地生