基于AT89C2051的TDS水质测试仪设计.doc

毕 业 设 计（论文） 2013 届 题 目 基于AT89C2051的TDS水质测试仪 专 业 电子信息工程 学生姓名 学 号 指导教师 论文字数 完成日期 2012-12-20 基于AT89C2051的TDS水质测试仪 摘 要：近些年来水环境的污染使得人们对水质越来越关注。水质检测仪对帮助人们了解水质情况起到了重要的作用。TDS水质检测仪以其结构简单，精巧实用，精度高，成本低，反应快等优点备受关注。TDS水质测试仪由于探头极化现象，寄生电容，温度对测量精度的影响, 使其存在测量精度低、温度补偿不够的缺点。针对这些现象，为了能够更精确测量水质，本研究分析了TDS测量的原理，对各种测量方法进行比较论证，设计了一款基于电导率测量原理和温度补偿误差的TDS水质测量仪。该电路设计以AT89C2051 单片机为核心，由传感器探头、电导率信号采集电路、温度补偿电路、控制电路、数码管显示电路和报警电路组成。系统引入了温度测量环节，通过软件算法补偿因温度变化引起的测量误差。 关键字： TDS , 水质检测 , 单片机 , 温度补偿 TDS Quality Dosimeters Based on AT89C2051 Abstract：In recent years water environmental pollution makes it increasingly concerned about water quality. Water quality testing instruments played an important role in helping people to understand the water quality. TDS water quality tester concern its structure is simple, compact, high-precision, low cost, fast response. TDS water tester due to the polarization of the probe, the parasitic capacitance, the temperature on the measurement accuracy, it exists the disadvantage of low measurement accuracy, the temperature compensation is not enough. For these phenomena, in order to be able to more accurately measure the water quality, this study analyzed the TDS measurement principle, a comparative demonstration of various methods of measurement, design a TDS water quality measuring instrument based on conductivity measurement principle and temperature compensation error. The circuit design AT89C2051 microcontroller as the core, the probe by the sensor, the conductivity signal acquisition circuit, temperature compensation circuit, control circuit, digital display and alarm circuits composed. The system introduces aspects of temperature measurement, the measurement error due to temperature changes caused by the software algorithm compensation. Key words：TDSWater quality testing MCU