设计简介
『摘要』大型货车在丘陵地带或坡道上行驶时需频繁或长时间刹车，会造成刹车鼓（盘）、制动蹄温度骤升，轮毂温度聚增，在剧烈高温下最终会导致刹车失灵，以及温度过高至使轮胎气压过高而出现爆胎现象而造成安全事故，通过对国内外刹车过热问题采取的解决方法的研究,最好的解决方案是设计出了一套大型货车制动过热自动控制系统装置,该系统由温度检测单元、液位检测单元、人机接口单元以及单片机控制单元等部分组成。该系统是以铂电阻PT100作为温度传感器，采用恒流测温的方法，通过单片机进行控制，用放大器、A/D转换器进行温度信号的采集。另外，还设计了时钟电路模块，能实现对温度的实时测量。本设计采用了两线制铂电阻温度测量电路，通过对电路的设计，减小了测量电路及PT100自身的误差，使温控精度在0℃～100℃范围内达到±0.1℃。本文采用AT89S51单片机，TLC2543 A/D转换器，DS1302时钟芯片，AD620放大器，铂电阻PT100及6位数码管组成系统，编写了相应的软件程序,使其实现温度的实时显示。该系统点是：使用简便；测量精确、稳定、可靠；测量范围大；使用对象广。主控芯片根据设定的温度条件输出控制信号,启动喷水设备对刹车系统降温;在手动方式下,也可以控制单片机启动喷水设备，降低刹车系统的温度。本课题对系统的硬件和软件进行分析说明，通过绘制相关的硬件连接图和软件流程图,建立系统软硬件模型，证明该系统可以实现对大型货车制动过热自动控制的功能。
『关键词』PT100，单片机，温度测量，DS1302
Abstract
Required frequent or prolonged braking when large Vehicles with goods driving on hills or ramps ,it will cause the brake drum (disk) , brake shoe temperature leapt hub ,at the same time, it will increase the truck skid system in the high temperature , eventually ,the result will cause severe brake failure, and the high tire pressure temperature is too high to make the phenomenon appear flat tire and caused accidents, according to research the solutions of overheated brakes in abroad, the best way solution is designing a new set of device .the set of device with the temperature self-control of the truck skid system inclusions the temperature detection unit, the level detection unit,the man-machine interface unit and the MCU control unit and other components. The system is based on a PT100 platinum resistance as temperature sensor, using the constant-current temperature method, through the single-chip microcomputer control, amplifier, A/D converter, temperature signal acquisition. In addition, also designed the clock circuit module, can realize the real-time measurement of temperature. This design adopts two wire platinum resistance temperature measurement circuit, the design of circuit, reduces the error of the measurement circuit and its PT100, the precision of temperature is 0 ℃ ~ 100 ℃ reach ± 0.1 ℃. This paper uses the AT89S51 microcontroller, TLC2543 A/D converter, DS1302 clock chip, AD620 amplifier, platinum resistance PT100 and the 6 digital tube system, compiled the corresponding software program, so as to realize the real-time display of temperature. The system is simple: use; measurement accuracy, stability, reliability; measurement range; widely used object.The main chip export the output control signal according to the main chip set temperature, to start to spraying equipment to cool the braking system; in the manual mode, you can start spraying equipment to reduce the temperature of the truck skid system. The topic of the device need hardware and software analysis ,it need establish the system hardware and software model by drawing the relevant hardware connection diagram and software flow chart , in order to prove that the device can realize the function of reducing the temperature of the truck skid system..
Keywords: PT100 MCU temperature measurement DS1302
中文摘要 Ⅵ
外文摘要 Ⅶ
1 绪论 5
1.1研究背景及意义 5
1.2国内外研究现状 6
1.3研究内容 6
2 温度测控系统设计方案 7
2.1温度测控系统的结构 7
2.2温度控制器功能设计 10
2.3执行机构 11
3 电路硬件设计 12
3.1PT100温度传感器特性和测温原理 12
3.2恒流源电路 13
3.3放大电路的设计 14
3.4A/D转换器的选择与设计电路 16
3.5DS1302时钟电路设计 18
3.6单片机控制电路 20
3.7按键和显示电路 24
3.8其他设备的选用 25
4 电路软件设计 28
4.1系统的软件程序流程图 29
4.2功能分析跟算法的选用 33
5 实验方案 34
5.1实验室模拟 36
5.2现场模拟 37
6 结论 38
参考文献 39
致谢 40
『关键词』PT100，单片机，温度测量，DS1302
Abstract
Required frequent or prolonged braking when large Vehicles with goods driving on hills or ramps ,it will cause the brake drum (disk) , brake shoe temperature leapt hub ,at the same time, it will increase the truck skid system in the high temperature , eventually ,the result will cause severe brake failure, and the high tire pressure temperature is too high to make the phenomenon appear flat tire and caused accidents, according to research the solutions of overheated brakes in abroad, the best way solution is designing a new set of device .the set of device with the temperature self-control of the truck skid system inclusions the temperature detection unit, the level detection unit,the man-machine interface unit and the MCU control unit and other components. The system is based on a PT100 platinum resistance as temperature sensor, using the constant-current temperature method, through the single-chip microcomputer control, amplifier, A/D converter, temperature signal acquisition. In addition, also designed the clock circuit module, can realize the real-time measurement of temperature. This design adopts two wire platinum resistance temperature measurement circuit, the design of circuit, reduces the error of the measurement circuit and its PT100, the precision of temperature is 0 ℃ ~ 100 ℃ reach ± 0.1 ℃. This paper uses the AT89S51 microcontroller, TLC2543 A/D converter, DS1302 clock chip, AD620 amplifier, platinum resistance PT100 and the 6 digital tube system, compiled the corresponding software program, so as to realize the real-time display of temperature. The system is simple: use; measurement accuracy, stability, reliability; measurement range; widely used object.The main chip export the output control signal according to the main chip set temperature, to start to spraying equipment to cool the braking system; in the manual mode, you can start spraying equipment to reduce the temperature of the truck skid system. The topic of the device need hardware and software analysis ,it need establish the system hardware and software model by drawing the relevant hardware connection diagram and software flow chart , in order to prove that the device can realize the function of reducing the temperature of the truck skid system..
Keywords: PT100 MCU temperature measurement DS1302
中文摘要 Ⅵ
外文摘要 Ⅶ
1 绪论 5
1.1研究背景及意义 5
1.2国内外研究现状 6
1.3研究内容 6
2 温度测控系统设计方案 7
2.1温度测控系统的结构 7
2.2温度控制器功能设计 10
2.3执行机构 11
3 电路硬件设计 12
3.1PT100温度传感器特性和测温原理 12
3.2恒流源电路 13
3.3放大电路的设计 14
3.4A/D转换器的选择与设计电路 16
3.5DS1302时钟电路设计 18
3.6单片机控制电路 20
3.7按键和显示电路 24
3.8其他设备的选用 25
4 电路软件设计 28
4.1系统的软件程序流程图 29
4.2功能分析跟算法的选用 33
5 实验方案 34
5.1实验室模拟 36
5.2现场模拟 37
6 结论 38
参考文献 39
致谢 40
