机电一体化毕业设计(论文)

机电一体化毕业设计（论文）

毕业设计任务书毕业设计题目：单片机控制直流电机的变速设计专业：机电一体化毕业设计的内容要求： 1. 有利于自动化，减少投资，提高生产率，稳定产品质量 2. 功能更强、性能更好 3.了解应用整机连接及性能测试。指导教师：系主任：年月日目录第一章总体设计方案·································································································1 方案选取······················································································································1 方案一：PWM波调速················································

(1)

方案二：晶闸管调速 (2)

第二章单元模块设计·································································································3 H桥电路方案设计······································································································3 调速设计方案···········································································································4 系统硬件电路设计······································································································5 电源电路···········································································································5 H桥驱动电路···································································································

...........5 2．5基于霍尔传感器的测速模块....................................................................................6 2．6 LCD 显示模块............................................................................................................7 调速设计模块...........................................................................................................8 测速软件设计............................................................................................................10 第三章系统功能调试. (1)

1 调试软件介绍············································································································11 直流电机的调速功能仿真························································································1

2 电机速度的测量并显示功能仿

真....................................................................................................13 系统的电路原理图....................................................................................................................................13 设计总结 (14)

山东华宇职业技术学院毕业设计用纸采用闸流管或汞弧整流器的离子拖动系统是最早应用静止式变流装置供电的直流方案二：晶闸管调速电动机调速系统。1957年，晶闸管问世，到了60年代，已生产出成套的晶闸管整流装置，并应用于直流电动机调速系统，即晶闸管可控整流器供电的直流调速系统。如图1-3，VT 是晶闸管可控整流器，通过调节触发装置GT的控制电压Uc来移动触发脉冲的相位，即可改变整流电压Ud，从而实现平滑调速。晶闸管整流装置不仅在经济

性和可靠性上都有很大提高，而且在技术性能上也显示出较大的优越性；晶闸管可控整流器的功率放大倍数在104以上，其门极电流可以直接用晶体管来控制，不再像直流发电机那样需要较大功率的放大器。因此，在60年代到70年代，晶闸管可控整流器供电的直流调速系统代替旋转变流机组直流电动机调速系统，得到了广泛的应用。但是于晶闸管的单向导电性，它不允许电流反向，给系统的可逆运行造成困难；晶闸管对过电压、过电流和过高的dudt与didt都十分敏感，若超过允许值会在很短的时间内损坏器件。另外，谐波与无功功率引起电网电压波形畸变，殃及附近的用电设备，造成“电力公害”，因此必须添置无功补偿和谐波滤波装置。图1-3 晶闸管可控整流器供电的直流调速系统兼于方案一调速特性优良、调整平滑、调速范围广、过载能力大，因此本设计采用方案一。 2 山东华宇职业技术学院毕业设计用纸