物料搅拌系统的PLC控制变频调速系统设计

辽宁科技大学本科生毕业设计（论文）第I页物料搅拌系统的PLC控制变频调速系统设计摘要随着电力电子技术以及控制技术的发展，使得交流变频调速在工业电机拖动领域得到了广泛应用。搅拌作为工艺过程的基础操作单元,广泛应用于石油、化工、医药、食品、油漆、涂料等许多行业。所以，基于PLC可靠性高、抗干扰能力强、系统的设计和建造工作量小、维护方便、容易改造的特点,设计以PLC作为控制核心,结合变频器等完成物料搅拌的自动控制系统。在本系统中，为了实现能源的充分利用和生产的需要，需要对电机进行转速调节，考虑到电机的启动、运行、调速和制动的特性，采用髙功能性的通用变频器西门子MICROMASTER420，能很好的解决转速之间的切换和启动问题。系统中由PLC完成数据的采集和对变频器、电机等设备的控制任务。本文首先介绍了课题的意义，综述了PLC技术、变频调速技术的发展概况。第二章详细的介绍了变频器的结构及其控制算法、变频调速的基本原理和变频调速的优点，然后介绍了西门子公司MM420变频器。第三章详细的介绍了PLC的基本构成和数据处理流程，然后详细的介绍了西门子公司S7-300PLC及其编程特点。第四章详细的介绍了系统的结构，硬件配置和软件实现。关键词：PLC；变频器；变频调速辽宁科技大学本科生毕业设计（论文）第II页DesignofACFrequencyConversionforSpeedadjustmentControlledbyPLCInMaterialsmixingsystemAbstractWiththedevelopmentofelectricelectrontechnologyandcontrollingtechnology,ACfrequencyconversionforspeedadjustmenttechnologyisusedwidelyinmanyfields.Materialsmixingarewidelyusedinpetroleum,chemical,pharmaceutical,food,paints,coatingsandmanyotherindustriesasthebasisfortheoperatingunit.PLCishighreliability,stronganti-jammingcapabilityandsmallconstructionworkload,maintainedandtransformedcharacteristicseasily,therefore,asthecontrolcoredesign,combinedwithinverter,automaticcontrolsystemofmaterialsmixingiscompleted.Inthissystem,inordertoachievefullutilizationofenergyandproductionneeds,adjustingthemotorspeedisneeded,withtakingintoaccountthemotorstart,run,speedandbrakingcharacteristics.WeusetheMM420ofSiemenstransducerwhosefunctionsofaddingordecreasingspeeding.Inthissystem,PLCisusedtocollectdatafromfieldsandcontrolequipment’ssuchaselectromotorandtransducer.Thispaperfirstlyintroducethemeaningofsubjects’summarizethedevelopmentofPLCtechnologyandACfrequencyconversionforspeedadjustment.Inthesecondchapter，weintroducethestructureoftransducerarithmeticofcontrolling,Basicprinciple,theadvantageofACfrequencyconversionforspeedadjustmentandMM420transducer.Inthethirdchapter,weintroducethestructure,characteristicflowchartofdatadisposalofconfigurationsoftwareindetailandparticularlyintroducetheSiemensS7-300PLCandcharacteristicsofsoftwaredesign.Inthefourthchapter,weintroducethestructureandtheimplementofsoftwareinthissystem.Keywords:PLC,Transducer,ACfrequencyconversionforspeedadjustment辽宁科技大学本科生毕业设计（论文）第III页目录摘要....................................................................................................................IAbstract.................................................................................................................II1绪论...................................................................................................................11.1概论...........................................................................................................11.2问题的提出及其解决方案.........................................................................................11.3论文的主要内容.........................................................................................................21.4相关技术发展概况.....................................................................................................21.4.1交流调速的发展概况......................................................................................21.4.2PLC技术的发展概况.......................................................................................42变频调速原理...................................................................................................62.1变频器的基本结构.....................................................................................................62.1.1变频器的主电路..............................................................................................62.1.2变频器的控制电路..........................................................................................72.2变频调速的基本原理.................................................................................................82.3变频调速的优点.......................................................................................................112.4西门子MM420变频器简介....................................................................................112.4.1MM420变频器的BOP操作面板.................................................................112.4.2MM420变频器的参数设置...........................................................................113PLC技术..........................................................................................................163.1PLC概述....................................................................................................................163.2PLC的基本组成与各部分的作用............................................................................163.2.1PLC的基本组成.............................................................................................163.2.2PLC各部分的作用.........................................................................................163.3A/D和D/A转换概念...............................................................................................183.3.1A/D和D/A原理.........................................................................................183.3.2模拟量输入输出系统....................................................................................18辽宁科技大学本科生毕业设计（论文）第IV页3.3.3输入输出数据的处