【作者】 许锦；

【导师】 李敏远；

【作者基本信息】 西安理工大学 ， 模式识别与智能系统， 2008， 硕士

【摘要】 本文研究设计了一个电参量智能测量仪,分别从硬件、软件两方面介绍了智能电参量测量仪的实现思想。系统的核心采用了单片机MSP430F449,研究主要内容包括:信号采样、数据处理、上下位机通信以及相关接口电路设计。测量仪在测量时能够自动选择合适的测量方法及量程进行测量,从而提高了测量精度并缩短了测量时间。在数据采集处理方面,采用了准同步法,去掉了同步环节从而减小了同步误差对测量值准确度的影响,同时采用一次加权复化梯形法减少了计算量。特别在针对高频信号测量时,采用等效-准同步采样法,实现了使用低速率A/D对高频率信号采样。还讨论了被测信号测量频率、相位差、电压/电流有效值、有功功率、功率因数等电参量的原理及方法,并通过理论分析所用方法产生的相对误差的大小以及影响相对误差的因素,再通过仿真验证后,提出相应措施,对硬、软件进行改进。采用Visual Basic开发了上位计算机的通信界面。将Modbus-RTU通信协议,嵌入于智能仪表中,实现上,下位机数据交换,便于实现远程测量和控制。另外为了适应现场测量便于携带,本仪表采用铅酸电池供电,并且完成了系统充电电路,使得仪表能够根据电池电量状态,自动进行充电或充电满断电。更多还原

【Abstract】 This text designed an the intelligence meter for electricity parameter,the both side from the hardware design and software design introduced an intelligence electricity parameter a test an instrument of design thought.The heart of the system is MSP430 single chip micyoco . They are mainly as follows:signal sample, data analysis, communicating module and peripheral interface circuit.Because of a wide frequency range and Amplitude with a wide range,we want to satisfy to measure accuracy higher and measure time as far as possible short,meust achieves auto-gearing.This mere collects processing aspect in the data, using quasi-synchronous sampling,throwing away synchronous link to let up synchronous error margin to the influence which measures an accurate degree, It throughs the use of composite trapezoidal integration,reduced the amount of computation.Adopt equivalent time-quasi-synchronous sampling while measuring to high frequency signal specially, carried out to use the low speed rate A/D to sample to the high frequency signal.It gives the measuring principle of some electric parameters as frequency/period,effective value of voltage and current,and power factor.It analyzes the main reasons that cause the measuring accuracy and gives the solutions to the specific problems on the high frequency.The simulation and experimental validation test the feasibility of its.Besides,it develops the communication interface on computer and the communication program developed by Modbus protocol .In order to facilitate the carrying another,it adoptions rechargeable sealed lead-acid battery,and design charging circuit,according to battery status, automatic recharge, or cut the power.更多还原