基于单片机的直流电机PWM控制系统.docVIP

摘 要 本文主要设计一个基于单片机的直流电机PWM控制系统。PWM控制提高了调速范围，提高了调速精度，改善了快速性能、功率和功率因数。系统在设计中被控对象采用5V的直流电机，以MCS-51单片机为控制核心，采用LCD1602液晶作为显示元件，进行软硬件的设计。硬件电路由protel设计制作，主要设计了液晶显示电路、键盘控制电路、时钟电路、复位电路、霍尔测速电路和驱动电路。软件设计在Keil开发平台用C语言编写，程序采用模块化设计方案，包括液初始化程序、晶显示程序、键盘控制程序、时钟中断程序。 本系统PWM控制直流电机采用调压调速的方法，整体设计包括软件和硬件两个部分。通过利用单片机产生PWM控制信号控制直流电机，详细介绍脉宽调制（PWM）控制原理，直流电机的工作原理和数学模型以及用H型桥电路基本原理设计的驱动电路。通过硬件电路的模拟情况，说明系统运行正常，各个功能模块实现是可行的，控制精度比较高，能够满足系统的基本要求。 关键字：单片机；PWM；直流电机 Abstract In this paper, it is designed by using PWM speed control system to control the speed of DC-motor based microcontroller. PWM speed control system can improve the speed range and speed accuracy, it also can improved speed performance, power and power factor. Controlled object in the design of the system is a 5V DC-motor controlled by MCS-51 microcontroller as the core, using LCD1602 as the display device. Based which we can begin the hardware and software design. The hardware circuit is designed by the software of Protel which contains the circuit design of the liquid crystal display, the keyboard control circuit, clock circuit and reset circuit, the Hall-speed circuit and drive circuit. Software development platform used in the Keil C language, the program is modular in design, including liquid crystal display program, the keyboard control program and clock interrupt routine. The system uses voltage DC-motor PWM speed control method. Overall design includes two parts of software and hardware design. The DC-motor is controlled through the use of single chip PWM control signal, and detailed pulse-width modulation (PWM) control theory, the working principle of DC-motor and mathematical models and H-bridge circuit with the basic principles of design of the drive circuit. Hardware circuit simulations, indicates that the system is operating normally and each functional module is feasible, especially control precision is relatively high. The system can meet the basic requirements.  Key words： Single Chip Microcontroller；PWM；DC-motor 目