基于STCC量程自动转换电压表设计说明书.docVIP

毕业设计说明书 基于量程自动转换电压表的设计 专业 自动化 学生姓名 班级 B自动化0 学号 指导教师 张胜超 完成日期 20年6月日 基于STC89C52量程自动转换电压表的设计 电工参数一般包括电流电压、功率、功率频率因数等。在电网调度自动化的设备中需要配置多只显示上述电工参数的面板表，如电表、电表、功率表等等，其一般为指针式面板表，精度，可视距离近，需要人工抄录数据，浪费人力资源，数据管理不便。近年，随着微电子技术的迅发展和大规模集成电路的出现，特别是单片机的出现，正在引起测量控制仪表领域的技术革命。 设计基于STC89C52 微控制器的量程自动转换电压表被测信号经输入阻抗分压衰减后得到与输入的被测电压成比例的电压值，并由运算放大器LM324按比例将其放大，最后经整流滤波得到与输入电压成比例的直流电压值。实现电压表量程的切换只需要改变放大电路的放大倍数即可。运算放大器是用电压负反馈比例放大由CD4051模拟开关进行Rf的选择，从而实现放大倍数的控制。再由单片机对A/D转换的结果进行，得到被测电压数值，通过单片机显示结果。 关键词：单片机；量程自动转换；A/D Design of Measuring Range Automatic Conversion Voltage Meter Based on STC89C52 Single Chip Computer Abstract: Electrical measuring parameters generally include current, voltage, power, power factor, frequency, etc. In the process of power grid dispatching automation equipment need to configure the display only the electrical parameters of the panel table, such as ammeter, voltage meter, power meter, its general table of pointer type panel, low precision, visual distance, and the need to manually transcribing data, not only waste of human resources, but also for data management of inconvenience. In recent years, with the rapid development of microelectronics technology and the emergence of large scale integrated circuit, particularly the emergence of single chip microcomputer, It is caused by the new technological revolution in the field of measuring control instrument. Based on STC89C52 microcontroller automatic conversion voltage meter range. Measured signal after input impedance differential pressure attenuation is proportional to input voltage being measured voltage value, and by the operational amplifier LM324 to enlarge it to scale, finally by the rectifier filter to get dc voltage is proportional to the input voltage value. Realize the voltmeter range switch you just need to change the magnification of amplifier circuit. Operational amplifier is proportion with voltage negative feedback amplifier by CD4051 for Rf analog switch selection, so as to realize the control of ma