【作者】 刘琳霞；

【导师】 沈安文；

【作者基本信息】 华中科技大学 ， 控制理论与控制工程， 2005， 硕士

【摘要】 用来计量电能的电能表,其精度十分重要。于是,检测和校验该类仪表准确度的电量计量校验仪应运而生,成为计量单位和供电部门重要的测试仪器。电能计量校验仪自身要能准确的检测各种电力参数,还要能够对其他电能表进行校验。在分析了目前国内外同类产品的设计方案之后,采用了专用电能计量芯片来实现系统的电参数测量部分,简化了系统的软硬件设计。专用芯片采样电流电压值并在其内部运算得出各参数值,微控制器从中读取数值并进行数据处理。基于CS5460A 开发的电能计量校验仪可以测得电流电压有效值及有功功率、功率因数; 基于ADE7758开发的功能更完善的电能计量校验仪还能实现无功功率、视在功率和频率的测量。通过扫描按键状态转入相应的操作流程来执行参数的显示、存储,对其他电能表的校验以及与上位机的通讯等功能。在分析了如何采用传统的前后台系统方式完成软件设计之后,选择了小型实时操作系统μC/OS-Ⅱ。首先完成了μC/OS-Ⅱ向ARM 微控制器的移植,随后针对各具体模块进行了驱动程序的开发,然后将系统功能划分为多个任务,并确定了各任务的优先级完成了应用程序的开发。两种编程方式对比之后,更深刻的理解了嵌入式实时操作系统的任务调度机理,并总结出了在检测仪表中引入小型实时操作系统的优点。实时操作系统的引入,使得系统的实时性、稳定性得以提高,增添新的功能也很方便。本文的最后给出了实验结果和误差分析,从实验结果可以看出,本设计方案基本达到了系统所要求的精度,具有一定的实用价值。更多还原

【Abstract】 The precision of power meters is very important. So calibration instrument of power measurement which to test precisions of this kind of instruments emerges as the time require. It’s very important for the power test and power supply departments. The calibration instrument of power measurement should have the ability to measure electrical parameters and vefify other power meters. After analyzing the design schemes of this kind of products demestic and abroad, special power chip is adopted to measure electrical parameters and the hardware and software design become compact. Special chip samples voltage and current and calculate electrical parameters. Mcu reads these parameters from it and does data processing. The calibration instrument based on CS5460A can measure the virtual value of voltage and current, active power and power factor. The enganced one based on ADE7758 can measure reactive power, visual power and frequency yet. Through scaning the key state, the program switch to the corresponding subprogram to display and save these parameters, calibrate other power meters and communicate with host computer. We select small real-time operation system μC/OS-Ⅱafter analyzing how to design program in foreground and background system. Firstly, μC/OS-Ⅱis ported to ARM mcu and then driver for each module are designed. At last, prioritiy for each task are confirmed and application programme is designed. After the compare of the two different ways, the task scheduling method of real-time operation system is understood clearly. And advantages of using real-time operation system in design of instruments are summed up. The characteristic of real time and stability of the system is enhanced, and new functions are easily enlarged. At last, error analyses and experiment results are provided. From the results, we can see the system achieve the expected request and have practicality.更多还原