基于飞思卡尔单片机电阻炉温度控制系统设计

I摘要在工业控制中，温度是一个很重要的参数。特别在冶金、机械、食品、化工等工业中，对工件的处理温度都要求严格控制，对于温度的精确度和稳定性均有较高的要求。随着大规模集成电路的发展，传统的模拟式温度控制器已逐渐被以微控制器如单片机、ARM、DSP和FPGA等为核心的数字控制器所替代。微控制器的出现不但使温度的控制方式由模拟式转变为数字式，而且其测量环节、滤波环节以及核心控制环节均变得易于设计和实现。本课题设计并开发了一款以飞思卡尔16位单片机为核心的温度控制器系统。控制系统包括核心控制器和外围电路两部分。其中外围电路包括传感器和变送器部分、执行器部分和被控对象部分。该控制系统使用的微控制器是Freescale公司推出的S12系列单片机中具有增强型的16位单片机MC9S12XS128，控制器采用PID控制算法。传感器和变送器部分采用铂热电阻对温度进行检测并用放大器进行放大，执行器受单片机输出的PWM控制。本控制系统的设计过程包括总体设计、硬件设计、软件设计和实验调试四大部分。关键字：飞思卡尔；PID；温度控制；Pt100IIAbstractIntheindustrialcontrol,thetemperatureisaveryimportantparameter.Thetemperatureaccuracyandstabilityhavehigherrequirements,especiallyinmetallurgy,machinery,food,chemicalindustry,whichrequirestrictcontrolontemperature.Withthedevelopmentoflarge-scaleintegratedcircuits,thetraditionalanalogtemperaturecontrollerhasgraduallybeenreplacedofMicrocontroller,suchasdigitalcontroller,ARM,DSPandFPGA.TheappearanceofMicrocontrollernotonlychangesthecontrolmodefromanalogtodigital,butalsomakesiteasiertorealizethedesignationonmeasuringelement,thefilterelementandthecorecontrolpart.Thisthesisistodesignatemperaturecontrolsystembasedona16Freescalemicrocontroller.Thetemperaturecontrolsystemcontainsacorecontrollerandperipheralcircuit.Theperipheralcircuitcomprisesasensorandtransmitter,actuatorandthecontrolledobjectpart.Thecontrollerusedinthecontrolsystemisthe16bitMCUMC9S12XS128withenhancedS12SeriesMCUproducedbyFreescalecompany,andthecontrollerappliesthePIDcontrolalgorithm.Sensorandtransmitterpartadoptsplatinumthermalresistancetodetecttemperatureandappliesamplifiertoamplifytheinputsignal.theactuatoriscontrolledbythesinglechipPWMoutput.Thecontrolsystemiscomprisedoftheoveralldesign,thehardwaredesign,thesoftwaredesignandthedebugging.Keywords:Freescale;PID;Temperaturecontrol;Pt100III目录1引言....................................................................................................................................11.1课题的研究背景及意义.........................................................................................11.2国内外研究现状.....................................................................................................21.3论文的整体结构.....................................................................................................32总体设计............................................................................................................................42.1温度控制器实现的功能.........................................................................................42.2结构框图.................................................................................................................42.3系统构成.................................................................................................................52.4被控对象分析.........................................................................................................52.5PID原理..................................................................................................................73硬件设计..........................................................................................................................103.1Protel简述..........................................................................................................103.2主控模块...............................................................................................................113.3通信模块...............................................................................................................133.4人机交互模块.......................................................................................................143.5电源模块...............................................................................................................163.6温度检测模块.......................................................................................................183.7调功调压模块设计...............................................................................................194软件设计..........................................................................................................................204.1软件开发环境——CodeWarrior简述................................................................204.2温度采集与处理程序...........................................................................................214.3人机交互程序.......................................................................................................234.4键盘处理程序.......................................................................................................264.5PID控制程序........................................................................................................335实验调试..........................................................................................................................355.1接线操作...............................................................................................................355.2功能介绍...............................................................................................................365.3温度控制器的基本功能测试...............................................................................375