单片机直流伺服控制系统设计方案.docx
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单片机直流伺服控制系统设计方案
单片机直流电机伺服控制系统设计摘要：
随着电子技术、功率元件技术和高性能的磁性材料制造技术的发展，伺服控制直流电动机利用电子换向器取代了机械电刷和机械换向器。
在各个领域得到了广泛的应用。
本文介绍了伺服控制直流电动机的发展及应用简况，全面分析伺服控制直流电动机的组成和原理。
着重点介绍伺服控制直流电动机调速系统硬件电路设计的同时详细介绍了PWM功率转换电路的设计、PWM系统驱动电路的设计及其相关的保护电路。
计算机控制已成为社会发展的趋势，在此还介绍了单片机系统的设计及其在调速系统中的应用。
关键词：
伺服控制直流电动机；AT80C51；单片机；调速系统设计
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Abstract：
Withthedevelopmentofelectronictechnology,powercomponenttechnologyandhigh-performancemagnetisablematerialmanufacturingtechnology,brushingthedirectcurrentmotorutilizesthereversingdeviceofelectrontoreplacethemechanicalelectricbrushandreversingdeviceofmachinery.Anditiswidelyusedineachfield.Thetextintroducesthedevelopmentanduseofthedirectcurrentmotorandtheoverview,analyseinanall-roundwaythattherearenotcompositionandprinciplewhichbrushesthedirectcurrentmotor.EmphasispointintroductionisitbrushdirectcurrentmotortransferspeedsystematichardwarecircuitrecommendPWMpowerchangethedesignofthecircuitindetailwhilethedesigntohave,PWMsystemdrivesthedesignofthecircuitandrelevantprotectioncircuit.Computerisitbecomesocialdevelopmenttrendalreadytocontrol,recommenddesign,one-chipcomputerofsystemandinapplicationinbeingsystematictotransferspeedalsohere.Keywords:
HavenotbrushedthedirectcurrentmotorAdjustthespeedtodesignsystematically8051single-chipcomputer
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目录1章伺服控制直流电动机概述·······································································51.1伺服控制直流电动机的特点·····················································································51.2伺服控制直流电动机的发展历史及研究应用现状·················································61.3本论文的主要内容·····································································································82章伺服控制直流电动机结构及工作原理····················································92.1伺服控制直流电动机的基本组成·············································································92.1.1电动机本体······································································································92.1.2位置传感器····································································································102.1.3电子换向线路································································································112.2伺服控制直流电动机的运行特性···········································································112.3机械特性和调速特性·······························································································132.4伺服控制直流电动机的脉宽调速···········································································143章伺服控制直流电动机的硬件设计··························································153.1系统组成····················································································································153.2单片机及接口电路设计···························································································163.2.1AT80C51的引脚及功能·················································································163.3电动机PWM的设计···································································································183.4电动机换相················································································································203.4.1电动机的换相原理·························································································203.4.2电动机的可逆换相························································································203.5转速环及电流环电路的设计····················································································213.5.1位置传感器·····································································································213.5.2转速环的设计································································································233.5.3电流传感器及电流环的设计········································································243.6系统保护环节的设计·······························································································253.6.1过压保护电路的设计····················································································253.6.2过流保护电路的设计··················································································263.7.3利用保护信号产生中断信号······································································273.8D/A转换电路的设计································································································273.8.1D/A芯片选择·································································································273.8.2DAC0832芯片介绍·······················································································293.8.3DAC0832芯片与单片机硬件接口设计·······················································313.8.4放大整形········································································································313.9显示电路及显示接口芯片选择···············································································323.9.1显示器的选择································································································323.9.2显示器工作方式的选择················································································343.9.3LED与单片机的接口电路设计····································································343.9.4按键电路的设计····························································································354章系统软件设计························································································374.1系统总程序···············································································································374.2D/A转换·················································································································384.3键扫描程序设计·······································································································394.4显示程序设计···········································································································40系统的调试······································································································425.1硬件的调试···············································································································42
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5.2软硬件调试···············································································································42致谢··················································································································44参考文献··············································································································45
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第1章
1.1伺服控制直流电动机的特点
伺服控制直流电动机概述伺服控制直流电动机概述
传统的直流电机以其优良的转矩特性和调速性能在运动领域中有着广泛的应用，但机械电刷却是它的致命弱点。
伺服控制直流电动机就是为了既要保持有刷直流电动机的特性、又要革除电刷和换向器的目的研究开发的。
控制系统中的执行电动机应该具有下列优点:
快速性、可控性、可靠性、体积小、重量轻、节能、效率高、适应环境和经济性。
下面将就这些方面具体分析伺服控制直流电动机的优点所在。
为了实现快速的起、停、加速、减速，要求电动机具有小的转动惯量和大的起动转矩和最大转矩，伺服控制直流电动机的转子主要是由永磁材料构成的磁极体组成，电枢绕组在定子上，因而转子外径可以相对较小，转子惯量也就较小。
转矩方面，只有直流电动机才能达到大的起动转矩和大的最大转矩，而伺服控制直流电动机具有直流电动机的特性，起动转矩和最大转矩都较大。
这使得它具有快速性的特点。
在可控性方面，直流电动机的输出转矩和绕组流过的电流成线性关系，直流电动机的起动转矩又大，因此可控性最好、最方便。
伺服控制直流电动机具有一般有刷直流电动机的调速特性，只要简单地改变电动机的输入电压的大小就可以在广阔的范围内进行无级调速。
在可靠性方面，消除了电刷，也就消除故障的主要根源，伺服控制直流电动机的转子上没有绕组，因而在转子上没有电的损耗，又由于主磁场使恒定的，因此铁损也是极小的，总的来说，除了轴承旋转产生摩擦损耗外，转子方的损耗很小，进一步增加了伺服控制直流电动机工作的可靠性。
由此可知，和其它类型的电动机相比，伺服控制直流电动机不仅较为可靠而且损耗较小，它的电枢在定子上，直接和机壳相连，散热条件好，热传导系数大。
由于这样的关系，在相同的条件下，在相同的出力要求下，伺服控制直流电动机可以设计得体积更小，重量更轻。
不论是电机设计还是系统设计，提高效率、节约能量都具有重要意义，有着长远的社会、经济效益。
据报道，美国55%以上的电力是消耗在电动机的运行上，美国GE公司曾预测，仅在制冷器具的应用中，若用伺服控制电机取代传统的异步电动机，其效率可提高20%，全美国一年可节约用电2.2MkWh。
而异步电动机运行在轻载时功率因素低，增加线路和电网的损耗，根据有关报导我国消耗在电动机上的电力占整个电力的65%以上。
因此，提高电动机的效率，选择损耗最小、效率最高的电机是很重要的。
从以上的分析可以看出，相对于其他类型的电机，伺服控制直流电动机的损耗最小、节能效率最高。
一份资料作过对比分析，对于7.5kW的异步电动机系统效率可达86.4%，但是同样容量的伺服控制直流电动机效率可达92.4%。
在环境适应性方面，对于高性能系统，只能采用直流电动机，但在同时要求长寿命，免
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维修以及防爆、防燃的环境条件下，有刷直流电动机就无法适应，伺服控制直流电动机才是最好的选择。
在经济性方面，随着电子技术的发展，电子元器件的价格不断的下降，伺服控制直流电动机驱动、控制器的价格己经和异步机的变频器相差不多了，只是由于稀土永磁材料的价格较贵，伺服控制直流电动机的成本也较高.但是在考虑综合指标（系统性能、重量、能量消耗）之后，伺服控制直流电动机的应用仍呈上升趋势。
表1.1是对目前应用较广的几种类型电动机基本性能所做的比较:
表1.1基本性能比较表基本性能电机类型直流电动机较高小小低较低大较小好较好一般较好短长长长高高低低效率体积控制特性技术性能结寿构命成本（电机本体）
伺服控制直流电高动机交流电动机开关磁阻电动机
1.2伺服控制直流电动机的发展历史及研究应用现状为了解决传统的直流电动机采用机械电刷进行换向带来的种种问题，在1917年，博利根（Boligen）提出用整流管代替传统的机械电刷以实现换流的思想。
1955年美国D.Harison等人申请了用晶体管换向线路代替有刷直流电机机械电刷的专利，标志着现代伺服控制直流电机的诞生。
70年代末、80年代初，随着电机技术及其相关学科的迅猛发展，伺服控制直流电机进入了实用阶段，先后研究成功方波和正弦波伺服控制直流电机，并且在计算机外设等领域开始应用，“伺服控制直流电机”的概念已由最初的具有电子换向的直流电机发展到。
泛指一切具有传统直流电机外部特性的电子换向电机。
80年代以来，伺服控制直流电机得到了迅猛的发展和推广应用，主要是由于大功率开关器件和大规模专用集成电路技术的高速发展。
性能优良的、价格低廉的电子元器件加快了伺服控制直流电机的更新换代步伐:
80年代与70年代同类型伺服控制直流电机相比较，体积缩小到只有原来的1/10，价格只有原来的1/10，从而提高了伺服控制直流电机的性能价格比，为其大量应用创造了先决条件。
高性能永磁材料，如影钻、钦铁翻的应用，也使伺服控制直流电机的性能提高和成本降低，为其得到广泛应用奠定了坚实的基础。
它作为机电一体化的高科技产物，在各个领域得到了广泛的应用，如计算机中的磁
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盘、光盘驱动器、CD唱机的光盘主轴驱动、随身听的磁带主动轮驱动、数控加工设备、宇航自动机器、各种记录仪和绘图仪笔的驱动等等。
进入90年代以来，伺服控制直流电机伺服系统的逆变装置中的开关元件不仅成本降低，而且向高频化、大容量、小型化、智能化发展，同时，永磁材料的性能不断提高和完善，加上永磁电机研究和和开发经验的逐步成熟，稀土永磁伺服控制直流电机的应用和开发进入一个新的阶段，目前正向大功率化（高转速、高转矩）、高功能化和微型化方向发展。
如今伺服控制直流电机集特种电机、变速机构、检测元件、控制软件与硬件于一体，己形成为新一代电动伺服系统，体现着当今应用科学的许多最新成果。
在国外，伺服控制直流电机己得到了较为充分的发展。
目前，在工业先进的国家（如美国、英国、日本、德国等）里，在工业自动化领域中已经实现了以伺服控制直流电动机代替有刷电动机的转换。
伺服控制直流电机还在其它领域得到了应用，如办公自动化领域、视听领域、汽车和电动车辆中的应用、现代家用电器中的应用。
而随着人们对环境问题和能源问题的日益关注，伺服控制直流电机在电动汽车中的应用更是成为近年来研究的热点，如美国福特汽车公司率先把伺服控制直流电机应用于电动汽车，并于90年代初推出了第三代电动轿车:
日本四国电力株式会社设计的电动小客车PIVOT由四个单机为6.8kW的伺服控制直流电动机驱动。
针对家电（空调、洗衣机）、电动车的使用，需要较高转速和高转矩的要求，日本HONDA公司开发了一种车用的伺服控制直流电动机，其转子是用非导磁的不锈钢将稀土磁体包卷嵌入转子迭片中，具有坚固可靠、输出力矩大和效率高（超过85%）的特点。
在我国，伺服控制直流电机的研制始于70年代初期，作为高科技产品受到了我国基础工业落后的制约，其综合水平低于国际水平。
目前，国内高校、研究单位开展伺服控制直流电机的研究己有时日，积累了丰富的设计理论和设计经验，只是由于自身条件而没有达到规模化生产，大部分仍处于仿真或实验阶段因此，应加强与生产厂家的合作，开发此类高科技产品并使之产业化。
如今，随着微电子技术的迅速发展和微处理器技术的日益更新，高速微处理器和DSP的出现，还有专用的控制芯片的出现，使得伺服控制直流电动机控制系统的运行速度、处理能力提高很大。
将来，随着这些器件的普及和应用的扩大，器件成本将大幅度地降价，因此性能明显更优秀的正弦波电流驱动的电动机会比方波驱动的电动机更受欢迎。
但是，正弦波电流驱动的电动机需要带更高精度的位置传感器，成本会更高一些，所以这些替代不是在任何场合下都适用，而是在要求高的情况下。
另外，在某些要求不高的
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