單片機控制的PWM直流電機調速系統的設計

電子機電論文編號:JD530 論文字數:19928,頁數:51

                                   目     錄
1 概論......................................................................1
1.1 直流電機調速原理.........................................................1
1.2 直流電動機的調速性能指標.................................................2
1.2.1 調速系統的穩態指標.....................................................2
1.2.2 調速系統的動態指標.....................................................3
2 閉環控制直流調速系統整體方案設計...........................................4
2.1 直流電動機的PWM控制原理..................................................4
2.2 直流電動機可逆PWM系統....................................................5
2.2.1 可逆PWM系統的原理.....................................................5
2.2.2 用單片機實現受限單極性控制.............................................7
2.38051 單片機對電動機控制的支持.............................................8
2.3.1  MCS-51單片機的基本組成................................................8
2.3.2 存儲器................................................................8
2.3.3 I/O 接口.............................................................9
2.4 單片機系統擴展及接口電路................................................10
2.4.1 EPROM的擴展..........................................................10
2.4.2 8051與ADC0809接口....................................................11
3 單片機控制PWM直流調速系統的硬件設計.......................................14
3.1系統方案介紹.............................................................14
3.2單片機控制PWM直流調速系統的電路設計......................................15
3.2.1主電路................................................................15
3.2.2驅動電路...............................................................16
3.2.3檢測回路...............................................................21
3.2.4保護電路設計...........................................................23
3.3 顯示模塊的設計與實現....................................................24
3.4 參數計算與元器件選擇....................................................24
4電流環和轉速環的設計.......................................................27
4.1電流環的設計.............................................................27
4.2轉速環的設計.............................................................27
5數字濾波與數字PID控制器設計................................................29
5.1數字濾波.................................................................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數字PID控制器的參數及采樣周期選擇........................................33
5.5.1 PID參數選擇...........................................................33
5.5.2采樣周期的選擇.........................................................33
6系統軟件設計...............................................................35
結束語......................................................................38
致謝.......................................................................39
參考文獻....................................................................40
附錄 原理圖及程序 ..........................................................41

摘   要
本課題是對雙閉環PWM直流調速系統的研究，主要實現對電動機的數字化控制。因此在設計中，對直流調速的原理，直流調速控制方式及調速特性，PWM基本原理及實現方式進行了全面闡述。
為實現系統的微機數字化控制，在設計中，采用了8051單片機作為整個控制系統的控制電路的核心部分，配以各種顯示、驅動、測量對模塊，實現對電動機轉速參數的顯示和測量；主電路由整流電路、濾波電路、即功率變換模塊組成，控制電路以單片微機為核心,組成包括電流檢測模塊、轉速檢測模塊、保護模塊。在設計中，采用PWM調速方式，通過改變PWM的占空比從而改變電動機的電樞電壓，進而實現對電動機的調速。為了提高控制系統的性能和可靠性，設計中，對電流環和轉速環采用PID調節器。在軟件實現中，本人采用位置式PID控制算法來實現對系統PID參數的整定，得到PID調節器的比例、積分、飽和積分修正系數、積分時間等參數，由于篇幅原因計算過程未列如本論文內容中，只是在最后程序中直接賦予各值。設計的整個控制系統，在硬件結構上采用了大量的集成電路模塊，大大簡化了硬件電路，提高了系統的穩定性和可靠性，使整個系統的性能得到提高。
關鍵詞：8051單片機；  PWM；  直流調速系統

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