基于单片机的自动调温风扇系统设计 -外文翻译.doc

本科毕业设计 （外文翻译）题 目 基于单片机的自动调 温风扇系统设计 姓 名 丁蒙恩 专 业 电子科学与技术 学 号 200931003 指导教师 张 军 郑州科技学院电气工程学院 二一三年五月外文翻译外文翻译原文：System design based on single chip microcomputer automatic temperature adjustment fan Temperature control fan in the modern social production and Peoples Daily life have a wide range of applications, such as industrial production and large mechanical cooling fan in the system, now widely used on laptops smart CPU fan, etc. Design based on single chip microcomputer temperature control fan system, this paper adopts the single chip microcomputer as controller, using temperature sensor DS18B20 as temperature gathering element, and according to the collected temperature through a darlington reverse drive driven ULN2803 fan motor. According to the detected temperature was compared with the system set the temperature of the implementation of the fan motor start and stop automatically, and can root temperature changes automatically changes the speed of the fan motor, at the same time with eight digital tube LED display temperature and setting temperature is detected.I. IntroductionWith the wide application of microcontroller in various fields, many of the temperature control system using single chip microcomputer as control also arises at the historic moment, such as system based on single chip microcomputer temperature control fan. It makes the fan according to the change of environmental temperature automatic start-stop, the fan speed changes with the change of environmental temperature, fan intelligent control is realized. Its design for the modern society has brought many convenient peoples life and production, to improve peoples quality of life, the production efficiency but also can save the energy for the fan operation. This paper was designed by the ATMEL company 8052 series single-chip computer AT89C52 as the controller, the temperature sensor by DALLAS company DS18B20 as temperature gathering element, and through a darlington reverse drive the rotation of the fan motor driven ULN2803. At the same time, make the system detected ambient temperature as well as the system default temperature dynamic display on LED digital tube. According to the system detects the ambient temperature and the comparison of the preset temperature, realize automatic start-stop of the fan motor and speed automatic adjustment. II. System Overall Structure Design Is the overall train of thought of this design: using temperature sensor DS18B20 testing environment temperature and directly output digital signals to single chip microcomputer AT89C52, on the LED digital tube display the current environment temperature and the preset temperature. The preset temperature can form as an integer, detects the current environment temperature can be accurate to one decimal place. At the same time adopts the PWM pulse width modulation method to change the dc fan motor speed. And through the two buttons to change the default value, a preset temperature, another reduce the preset temperature. III. the unit modules hardware design System mainly includes device DS18B20 temperature sensor, and AT89C52 single-chip microcomputer and five LED digital tube, fan Yin reverse drive dc motor, darlington ULN2803. Auxiliary components include resistors capacitors, crystal vibration, power supplies, buttons, dial the code switch, etc.3.1 part of the system devices A.DS18B20 single line digital temperature sensor DS18B20 digital temperature sensor, is using the American DALLAS semiconductor company production of DS18B20 digital temperature sensor networking chip packaging, it has the miniaturization, low power consumption, high performance, strong anti-interference ability, easy to match advantage such as microprocessors, temperature can be directly converted to a serial digital signal processor for processing. The main characteristic of DS18B20: measuring results directly in the form of a digital signal output, with "1-wire bus" means serial port sent to the CPU, can send CRC check code at the same time, with strong ability of anti-interference error correction; Temperature measurement range between - 55 + 125 , at - 10 + 85 accuracy of plus or minus 0.5 ; Detects the temperature resolution for 9 12, corresponding distinguished temperature 0.5 , respectively, 0.25 , 0.125 and 0.0625 , which can realize high precision temperature measurement; The uniqueness of the single wire interface, it makes only a port when it is connected with the microprocessor line can be realized with the two-way communication of the microprocessor; Support more network function, that is, multiple DS18B20 can be parallel on only three lines, achieve network function of multipoint temperature measurement; Wide working voltage range, the range from 3.0 V to 5.5 V. DS18B20 internal structure mainly has four parts: a 64 - bit ROM, the temperature of the temperature sensors, nonvolatile alarm trigger TH and TL, the configuration register. The pin has three, the DQ for digital signal, GND for power supply, VDD power input end. B.Introduction to the AT89C52 single chip microcomputer Is one of the 51 series single chip microcomputer AT89C52 model, it is produced by the ATMEL company a low voltage, high-performance 8-bit microcontroller, on chip device adopts nonvolatile of ATMEL company, high-density storage technology production, compatible with standard of MCS - 51 command system, at the same time with general 8-bit CPU and 8 k bytes can be repeatedly wipe read-only program memory RAM, ROM and 256 gigabytes of data memory in many, many more complex control system is AT89C52 single chip microcomputer has been widely used. AT89C52 40 pin. 3.2 part of the circuit design A.Switch is reset and crystal oscillator circuit In microcomputer application system, in addition to the microcontroller itself needs to be reset, external expansion I/O interface circuit also need to be reset, so you need a system, including electricity and button to reset synchronous reset circuit. Single-chip microcomputer XTAL1 and XTAL2 for external quartz crystal and fine-tuning capacitor, which used to connect the MCU chip OSC time feedback loop. This switch is reset and crystal oscillator circuit in the design of as shown in the figure below, when press the button switch S1, system reset at a time. For 20 pf capacitor C1, C2, C3 is 10 uf, the 10 k resistor R2, and R3, crystals of 11.0592 MHz. B.Temperature acquisition circuit DS18B20 digital temperature sensor by counting its internal clock cycles to effect, achieve the function of peculiar temperature measurement. Low temperature coefficient of the clock oscillator output signal generated by high temperature coefficient of oscillators door was counting cycles, and counter with advance and 55 corresponding weights of a base. If counter count to zero, the high temperature coefficient of oscillation period is not over, said the measured temperature value is higher than 55 , were prepared in the register - 55 temperature increases, the value 1 , and the process repeats itself, until the end of the high temperature coefficient of oscillation cycle. Temperature register at this time of the measured temperature value, value is the value stored in memory in the form of a 16-bit binary, sent by the host memory read command to read the temperature value, when read in low, high,. Because of the influence of the temperature oscillator parabolic characteristics, which use the slope accumulator to compensate. C.Fan motor drive and control circuit Of MCU I/O mouth in the design of the PWM output pulse, through a darlington reverse drive driven ULN2803 12 v brushless dc fan motor and fan motor speed regulation. Keyboard set temperature control, through the software corresponding input to the MCU control instruction, by single-chip microcomputer through P1.7 port output and speed corresponding PWM pulse, after driven ULN2803 fan motor control circuit, realize automatic control of motor speed and the rev. Stop. When environment temperature, the dc motor speed will be in accordance with the corresponding set level increased; When environment temperature drop, the motor speed will accordingly decrease; When environment temperature is below the set temperature, the motor stop running, and the environment temperature is higher than the preset temperature, the motor is restarted. IV .The software design Software design includes application Settings, programming and software simulation. Program design part mainly includes the main program, DS18B20 initialization function, DS18B20 temperature conversion function, temperature reading functions, the keyboard scanning function, digital tube display, temperature processing function and control function of the motor. DS18B20 initialization function of DS18B20 initialization; DS18B20 temperature conversion function complete real-time collection of temperature; Temperature reading function complete host on the temperature sensor data reading and data conversion, keyboard scanning function is set according to the need to complete initial value and subtract; Temperature processing function to analyze the collected temperature, provide the conditions for motor speed changes; Fan motor control function was completed according to the temperature of the numerical control of motor speed and rev. Stop. With Proteus simulation Proteus has four function modules: the first smart principle diagram design, complete the circuit simulation function, unique collaborative simulation microcontroller and practical platform for the PCB design. Its internal components library contains rich components to support intelligent bus structure and attachment function; Support mainstream CPU (such as ARM, 8051/52, AVR) and its general real-time simulation model of the peripheral, etc., brings great convenience for the development and application of single-chip microcomputer, etc. Start the Proteus software and establish a project, and then according to the principle diagram of the corresponding original, again according to the request to change the original properties and connect various components according to the principle diagram. In the schematic drawing good connection and then loads the compiled program to them. According to the simulation system to realize the function step by step. CONCLUSIONthis system can be used in simple daily fan intelligent control, bring convenience for the life; In industrial production, can change the different input signal, the implementation of different control motor speed signal input, and then realize the production automation, such as in power system can achieve different according to different load voltage signal, again by the generator voltage signal to adjust different rotating speed, and then adjust the power, realize the automation of electric power system. To sum up, the system design and research has the important status in social production and life.译文：基于单片机的自动调温风扇系统设计温控风扇在现代社会中的生产以及人们的日常生活中都有广泛的应用，如工业生产中大型机械散热系统中的风扇、现在笔记本电脑上的广泛应用的智能CPU风扇等。本文设计了基于单片机的温控风扇系统，采用单片机作为控制器，利用温度传感器DS18B20作为温度采集元件，并根据采集到的温度，通过一个达林顿反向驱动器ULN2803驱动风扇电机。根据检测到的温度与系统设定的温度的比较实现风扇电机的自动启动和停止，并能根温度的变化自动改变风扇电机的转速，同时用LED八段数码管显示检测到的温度与设定的温度。1 简介随着单片机在各个领域的广泛应用，许多用单片机作控制的温度控制系统也应运而生，如基于单片机的温控风扇系统。它使风扇根据环境温度的变化实现自动启停，使风扇转速随着环境温度的变化而变化，实现了风扇的智能控制。它的设计为现代社会人们的生活以及生产带来了诸多便利，在提高人们的生活质量、生产效率的同时还能节省风扇运转所需的能量。本文设计了由ATMEL公司的8052系列单片机AT89C52作为控制器，采用DALLAS公司的温度传感器DS18B20作为温度采集元件，并通过一个达林顿反向驱动器ULN2803驱动风扇电机的转动。同时使系统检测到得环境温度以及系统预设的温度动态的显示在LED数码管上。根据系统检测到得环境温度与系统预设温度的比较，实现风扇电机的自动启停以及转速的自动调节。2 系统整体结构设计本设计的整体思路是：利用温度传感器DS18B20检测环境温度并直接输出数字温度信号给单片机AT89C52进行处理，在LED数码管上显示当前环境温度值以及预设温度值。其中预设温度值只能为整数形式，检测到的当前环境温度可精确到小数点后一位。同时采用PWM脉宽调制方式来改变直流风扇电机的转速。并通过两个按键改变预设温度值，一个提高预设温度，另一个降低预设温度值。3各单元模块的硬件设计系统主要器件包括DS18B20温度传感器、AT89C52单片机、五位LED共阴数码管、风扇直流电机、达林顿反向驱动器ULN2803。辅助元件包括电阻电容、晶振、电源、按键、拨码开关等。3.1部分系统器件简介(1) DS18B20单线数字温度传感器简介 DS18B20数字温度传感器，是采用美国DALLAS半导体公司生产的DS18B20可组网数字温度传感器芯片封装而成，它具有微型化、低功耗、高性能、抗干扰能力强、易配微处理器等优点，可直接将温度转化成串行数字信号供处理器处理。适用于各种狭小空间设备数字测温和控制领域。 DS18B20的主要特征：测量的结果直接以数字信号的形式输出，以“一线总线”方式串行传送给CPU，同时可传送CRC校验码，具有极强的抗干扰纠错能力；温度测量范围在-55+125之间，在-10+85时精度为0.5；可检测温度分辨率为912位，对应的可分辨温度分别为0.5，0.25，0.125和0.0625，可实现高精度测温；它单线接口的独特性，使它与微处理器连接时仅需一条端口线即可实现与微处理器的双向通信；支持多点组网功能，即多个DS18B20可以并联在唯一的三线上，实现组网多点测温的功能；工作电压范围宽，其范围在3.05.5V。 DS18B20内部结构主要有四部分：64位ROM、温度传感器、非挥发的温度报警触发器TH和TL、配置寄存器。其管脚有三个，其中DQ为数字信号端，GND为电源地，VDD为电源输入端。(2) AT89C52单片机简介 AT89C52是51系列单片机的一个型号，它是由ATMEL公司生产的一个低电压、高性能的8位单片机，片内器件采用ATMEL公司的非易失性、高密度存储技术生产，与标准的MCS-51指令系统兼容，同时片内置有通用8位中央处理器和8k 字节的可反复擦写的只读程序存储器ROM以及256 字节的数据存储器RAM，在许多许多较复杂的控制系统中AT89C52单片机得到了广泛的应用。AT89C52有40个引脚。3.2部分电路设计（1）开关复位与晶振电路 在单片机应用系统中，除单片机本身需要复位以外，外部扩展I/O接口电路也需要复位，因此需要一个包括上电和按钮复位在内的系统同步复位电路。单片机上的XTAL1和XTAL2用来外接石英晶体和微调电容，即用来连接单片机片内OSC的定时反馈回路。本设计中开关复位与晶振电路如下图所示，当按下按键开关S1时，系统复位一次。其中电容C1、C2为20pF，C3为10uF，电阻R2、R3为10k，晶振为11.0592MHz。（2）温度采集电路 DS18B20数字温度传感器通过其内部计数时钟周期来的作用，实现了特有的温度测量功能。低温系数振荡器输出的时钟信号通过由高温度系数振荡器产生的门周期而被计数，计数器预先置有与-55相对应的一个基权值。如果计数器计数到0时，高温度系数振荡周期还未结束，则表示测量的温度值高于-55，被预置在-55的温度寄存器中的值就增加1，然后这个过程不断重复，直到高温度系数振荡周期结束为止。此时温度寄存器中的值即为被测温度值，这个值以16位二进制形式存放在存储器中，通过主机发送存储器读命令可读出此温度值，读取时低位在前，高位在后，依次进行。由于温度振荡器的抛物线特性的影响，其内用斜率累加器进行补偿。（3）风扇电机驱动与调速电路本设计中由单片机的I/O口输出PWM脉冲，通过一个达林顿反向驱动器ULN2803驱动12V直流无刷风扇电机以及实现风扇电机速度的调节。键盘控制设置温度，通过软件向单片机输入相应控制指令，由单片机通过P1.7口输出与转速相应的PWM脉冲，经过ULN2803驱动风扇直流电机控制电路，实现电机转速与启停的自动控制。当环境温度升高时，直流电机的转速会相应按照设定的等级有所提高；当环境温度下降时，电机的转速会相应的下降；当环境温度低于设置温度时，电机停止转动，而环境温度又高于预设温度时，电机重新启动。4软件设计软件设计包括程序设置，编写程序以及软件仿真。程序设计部分主要包括主程序、DS18B20初始化函数、DS18B20温度转换函数、温度读取函数、键盘扫描函数、数码管显示函数、温度处理函数以及风扇电机控制函数。DS18B20初始化函数完成对DS18B20的初始化；DS18B20温度转换函数完成对环境温度的实时采集；温度读取函数完成主机对温度传感器数据的读取及数据换算，键盘扫描函数则根据需要完成初值的加减设定；温度处理函数对采集到的温度进行分析出理，为电机转速的变化提供条件；风扇电机控制函数则根据温度的数值完成对电机转速及启停的控制。 用Proteus进行仿真首先Proteus有4个功能模块：智能原理图设计、完善的电路仿真功能、独特的单片机协同仿真功能以及实用的PCB设计平台。其内部元件库含有丰富的元件，支持总线结构以及智能化的连线功能；支持主流CPU（如ARM、8051/52、AVR）及其通用外设模型的实时仿真等，为单片机的开发应用等带来极大的便利。启动Proteus软件并建立一工程，然后根据原理图调出相应的原件，再根据要求改变各原件的属性并把各个原件按原理图连接起来。在原理图绘制连接好后再把编译好的程序加载到其中。最后根据系统要实现的功能分步进行仿真。总结 本系统设计可推广到各种电动机的控制系统中，实现电动机的转速调节。在生产生活中，本系统可用于简单的日常风扇的智能控制，为生活带来便利；在工业生产中，可以改变不同的输入信号，实现对不同信号输入控制电机的转速，进而实现生产自动化，如在电力系统中可以根据不同的负荷达到不同的电压信号，再由电压信号调节不同的发电机转速，进而调节发电量，实现电力系统的自动化调节。综上所述，该系统的设计和研究在社会生产和生活中具有重要地位。9