【作者】 郭军杰；

【导师】 丁汉；

【作者基本信息】 上海交通大学 ， Mechanical and Electronics Engineering， 2008， 硕士

【摘要】 本文主要阐述了以Master MCU(ARM9 S3C2410)与Slave MCU(ARM7 ADuC7022)为核心处理器设计的一款基于嵌入式Linux操作系统的多通道三相/单相交流网络电参数测量仪,用其可以同时监测多个用电设备的电压、电流、有功功率、功率因素、累积功等参数,并实现了通过网络远程监测电参数,历史数据自动保存等功能。通过优化常用采样电路的方案设计,采用了电流分段采样的方法,提高了测量精度和扩大了测量范围。改进了常用的周期中断信号产生电路,软件上合理安排中断优先级,通过调整电流、电压采样瞬时值对应关系,软件补偿了电流、电压输入到A/D转换电路造成的不同位差偏移,提高了功率和功率因数的精度。根据电流、电压和功率的计算原理使瞬时值采样发生在等间隔区域时间的中点,利用了ADuC7022高速采样的特性,合理分布采样点数,极大地减少了非同步采样原理性误差,降低了对信号频率的敏感性。通过采用平均采样值算法,在现有硬件噪声干扰较重的条件下消除多种随机误差,大幅提高了测量结果的稳定性和精度。SD卡存储器的设计使其能在不连接计算机的情况下独立工作并自动保存历史数据。通过软件仿真和大量的实验加以验证本设计方案,最终使其达到预定的指标。通过多通道测量和SD卡存储器的设计,硬件电路和软件程序的优化,可增强电参数测量仪的使用便利性。在设备的状态远程监测和自动化系统中有很广泛的应用前景。更多还原

【Abstract】 This paper presents an embedded multi-channel IP Power Meter which could be used to measure key parameters of single-phase or three-phase AC through network. Using the ARM9 S3C2410 and the ARM7 ADuC7022 as the master MCU and slave MCU respectively and the embedded Linux OS as the operating system, the power meter could be used to measure electric parameters such as the voltage, current, power and power factor for multiple instruments simultaneously. In the mean time, the system can be monitored via network and display, analyze the electric parameters, save the history data in SD card automatically. In order to improve the accuracy and enlarge range of the measurement, the sampling circuit scheme is optimized by removing the sample-and-holder and sampling the current with the two different amplifiers. Moreover, the circuit for periodic interruption is improved to debase the noise in the low-cost hardware scheme, and the interruption priority has been assigned reasonably to get precise watt and power factor result. Random errors are reduced by the algorithm averaging the sample values, and phase difference is compensated by adjusting the relative relationship of the sampled voltage and current value. The performance of the IP power meter is verified by software simulation and sufficient experiments.With the design of multi-channel measurement and SD memory cards, the optimization of hardware and firmware, the power meter which is proved to be low-cost,convenient,accurate is believed to be useful in the remote monitoring and automated systems.更多还原