单片机控制的PWM直流电机调速系统的设计

论文编号:JD530 论文字数:19928,页数:51，附电路图

摘   要
本课题是对双闭环PWM直流调速系统的研究，主要实现对电动机的数字化控制。因此在设计中，对直流调速的原理，直流调速控制方式及调速特性，PWM基本原理及实现方式进行了全面阐述。
为实现系统的微机数字化控制，在设计中，采用了8051单片机作为整个控制系统的控制电路的核心部分，配以各种显示、驱动、测量对模块，实现对电动机转速参数的显示和测量；主电路由整流电路、滤波电路、即功率变换模块组成，控制电路以单片微机为核心,组成包括电流检测模块、转速检测模块、保护模块。在设计中，采用PWM调速方式，通过改变PWM的占空比从而改变电动机的电枢电压，进而实现对电动机的调速。为了提高控制系统的性能和可靠性，设计中，对电流环和转速环采用PID调节器。在软件实现中，本人采用位置式PID控制算法来实现对系统PID参数的整定，得到PID调节器的比例、积分、饱和积分修正系数、积分时间等参数，由于篇幅原因计算过程未列如本论文内容中，只是在最后程序中直接赋予各值。设计的整个控制系统，在硬件结构上采用了大量的集成电路模块，大大简化了硬件电路，提高了系统的稳定性和可靠性，使整个系统的性能得到提高。
关键词：8051单片机；  PWM；  直流调速系统

Abstract
The subject of double-loop DC PWM speed control system, the main motor of the digital control. Therefore the design of the DC converter principle DC converter control and speed characteristics, PWM basic principles and ways for a full explanation.
To achieve the computer digital control, in terms of design, used 8051 as a whole control system of the control circuit core, and with all that driving, Measurement of modules to achieve the parameters of the motor speed display and measurement; rectifier circuit by circuit, the filter circuit, that the power conversion module components, the control circuit for a microcomputer core consists of current detection module, speed detection module, protection module. In the design, using PWM speed control mode by changing the duty cycle of the PWM thus changing the motor armature voltage, thereby realizing the right motor speed control. In order to improve the control system performance and reliability, and design, the current loop and speed loop PID regulator. In software, I used location PID control algorithm to achieve the right system PID tuning parameters, PID controller is the ratio of integrals, integral saturation correction factor, the parameters such as integration time, Due to reasons of space calculation unmanifested as if this thesis, it is in the final process directly give the value. Design of the entire control system, the hardware structure using a large number of IC module greatly simplifies the hardware circuit, improve the system's stability and reliability of the whole system performance is improved.
Keywords ： 8051;  PWM;  DC converter system

                                   目     录
1 概论......................................................................1
1.1 直流电机调速原理.........................................................1
1.2 直流电动机的调速性能指标.................................................2
1.2.1 调速系统的稳态指标.....................................................2
1.2.2 调速系统的动态指标.....................................................3
2 闭环控制直流调速系统整体方案设计...........................................4
2.1 直流电动机的PWM控制原理..................................................4
2.2 直流电动机可逆PWM系统....................................................5
2.2.1 可逆PWM系统的原理.....................................................5
2.2.2 用单片机实现受限单极性控制.............................................7
2.38051 单片机对电动机控制的支持.............................................8
2.3.1  MCS-51单片机的基本组成................................................8
2.3.2 存储器................................................................8
2.3.3 I/O 接口.............................................................9
2.4 单片机系统扩展及接口电路................................................10
2.4.1 EPROM的扩展..........................................................10
2.4.2 8051与ADC0809接口....................................................11
3 单片机控制PWM直流调速系统的硬件设计.......................................14
3.1系统方案介绍.............................................................14
3.2单片机控制PWM直流调速系统的电路设计......................................15
3.2.1主电路................................................................15
3.2.2驱动电路...............................................................16
3.2.3检测回路...............................................................21
3.2.4保护电路设计...........................................................23
3.3 显示模块的设计与实现....................................................24
3.4 参数计算与元器件选择....................................................24
4电流环和转速环的设计.......................................................27
4.1电流环的设计.............................................................27
4.2转速环的设计.............................................................27
5数字滤波与数字PID控制器设计................................................29
5.1数字滤波.................................................................29
5.2 PID控制原理.............................................................30
5.3位置式PID控制算法........................................................31
5.4增量式PID控制算法........................................................32
5.5数字PID控制器的参数及采样周期选择........................................33
5.5.1 PID参数选择...........................................................33
5.5.2采样周期的选择.........................................................33
6系统软件设计...............................................................35
结束语......................................................................38
致谢.......................................................................39
参考文献....................................................................40
附录 原理图及程序 ..........................................................41