【作者】 杨敏；

【导师】 滕召胜；

【作者基本信息】 湖南大学 ， 控制科学与工程， 2009， 硕士

【摘要】 电子分析天平是高精度质量计量仪器,广泛应用于国防、科研、贸易、化工、医药、电子、冶金等领域,具有称量准确度高、响应速度快、稳定性好、自动校准、操作方便等特点。本文设计的电子分析天平以低功耗单片机MSP430F449为信息处理核心,以24位高精度Δ-Σ型A/D转换器CS5532为信号采集单元,利用数据预处理、非线性校正、温漂自动补偿、智能零点跟踪等技术提高其工作的准确度和稳定性。首先,简单介绍电子分析天平的发展历史、分类、国内外发展状况及趋势,指出本课题研究的意义。分析电子分析天平的系统构成和电磁力平衡传感器的工作原理,给出电子分析天平系统的传感器与模拟电路、数据采集电路以及单片机系统电路的设计。其次,系统分析电子分析天平的软件设计,包括功能需求分析和软件的模块化设计,详细给出信号输入、人机接口以及数据处理等模块的程序设计方法。设计出具有去皮、称量、校准、数据存储、通信、零点自动跟踪、故障自诊断、性能测试等功能的电子分析天平,并实现了上位机虚拟面板的操作功能。然后,研究电子分析天平的信息处理方法。提出自适应均值滤波算法和多级阈值判别算法,提高了电子分析天平的灵敏度和稳定性;采用牛顿插值与LSM相结合的非线性校正方法,有效地改善了系统的非线性;建立温漂补偿模型,实现温漂自动补偿,并利用定时校准和零点跟踪技术,实现时漂自动补偿。最后,在室温条件下,结合电子分析天平的计量性能要求和技术指标,对电子分析天平进行整机实验测试,检验电子分析天平偏载误差、重复性和示值误差的性能指标。实验结果表明,采用上述方案设计的电子分析天平在室温条件下完全满足量程为210g、感量为0.1mg、最大允许误差≤0.3mg的设计要求,而且稳定性好、灵敏度高、可靠性好。更多还原

【Abstract】 Electronic analytical balance is the high-precision instruments for mass measurement and it is widely used in national defense, scientific research, trade, chemical, pharmaceutical, electronics, metallurgy and other fields. Electronic analytical balance is weighing with high accuracy and fast response, good stability, automatic calibration, easy to operate and so on.In this thesis, the electronic analytical balance is designed by using low-power single-chip MSP430F449 as the information processing core and high-precision 24-bitΔ-ΣA/D converter CS5532 for signal acquisition unit. The technology of data pre-processing, non-linear correction, automatic temperature compensation and smart zero-tracking is adopted to enhance its accuracy and stability.Firstly, a brief introduction is given, including the development history, the classification and the development trend at home and abroad of the electronic analytical balance. The significance of this research is indicated. The system composition and the electromagnetic force balance sensor of the working principle of electronic analytical balance are analyzed, The design of electronic analytical balance system sensor and analog circuits, data acquisition circuit and the circuit design of single-chip microcomputer system was introduced.Secondly, the system analysis of electronic analytical balance software design was discussed, which includes functional requirements and modular software design. The methods of Modular programming for signal input module, man-machine interface and data-processing module are given in details.The electronic analytical balance is designed with tare, weighing, calibration, data storage, communications, automatic zero-tracking, fault self-diagnosis, performance testing and other functions.And also the virtual PC operation panel function is completed.Thirdly, the information processing methods of electronic analytical balance are studied. Adaptive average filtering algorithm and the threshold level multi-discriminant algorithm are presented, which could enhance the sensitivity and stability of electronic analytical balance; the method of Newton interpolation with LSM(least squares method) combined is applied to improve the nonlinearity of system; and the temperature drift compensation models is established to realize the temperature drift automatic compensation of electronic analytical balance, with the use of regular calibration and zero-tracking technology, the time drift automatic compensation is realized.Finally, according to the measurement of performance requirements and technical specifications of electronic analytical balance, we have completed the experiment test to examine the partial load error, repeatability error and indication error in room temperature.The experimental results show that the above-mentioned design of electronic analytical balance meets the design requirements with scale range of 210g, accuracy of 0.1mg, the maximum allowable error≤0.3mg in room temperature. And it has good stability, high sensitivity and high reliability.更多还原