【作者】 黄锦华；

【导师】 陈若珠； 骆东松；

【作者基本信息】 兰州理工大学 ， 系统工程， 2010， 硕士

【摘要】 随着电力电子技术的发展,越来越多的非线性设备应用到电力系统中,电网中的谐波污染日益严重,危及电力系统安全,增加了运行的损耗,影响用户的正常工作。因此,为了保证供电系统安全经济运行和维护用户人身和设备安全,对电力系统的谐波进行实时检测、分析和监控具有重要的意义。传统的电能质量分析和监控系统中一般用普通单片机作为核心部件,但由于普通单片机运算速度有限,无法进行高频率采样和实时分析数据,因此在实际测量中的采样点数被严重限制,数据分析的精度降低。近年来数字信号处理器(DSP)的发展使得高速采样、存储和实时处理数据成为现实。DSP采用先进的改进型哈佛结构,其程序存储器和数据存储器具有各自的总线结构,可以同时处理指令和数据,大大提高谐波测量的精度。在谐波测量算法和电子技术进步基础上,市场上谐波测量设备越来越多。国外研制的仪器精度高,功能强大,但是价格普遍偏高。国内的仪器大多精度较低,且功能不全。本课题参照相关国家谐波测量的相关标准、市场所上同类产品的技术指标和实际应用的要求,研制了一种基于高速DSP和快速傅里叶变换算法的谐波测量仪。它具有精度高、功能齐全、价格低廉等优点。本课题首先在对现有的谐波测量算法比较的基础上,选择最常用的快速傅里叶变换谐波变换(FFT)算法并对其进行了较详细的研究,明确了FFT的优缺点,并针对其缺点运用加窗插值方法加以改善。其次,了解市场上同类产品的技术指标和实际应用的要求,选择合适的电子元器件,设计了谐波测量仪的硬件结构。测量仪硬件的组成部分包括：信号采集模块、谐波测量模块、人机接口模块和串口通信模块等。再次,设计了测量仪的软件。软件分为几个子程序：数据采集子程序、数据处理子程序、通信子程序和上位机软件等。通过合理地调用各个子程序完成信号采集、数据处理及存储、通信和测量结果的显示等功能。最后,用谐波产生仪器产生多次谐波,并用设计出来的测量仪进行测量,分析测量结果,找出误差产生的原因,对系统进行调整,最后测量结果达到了预期效果。试验表明,本文提出的基于DSP的谐波测量仪具有较高的测量速度和测量精度。它具有速度快、精度高和运行稳定等优点,是一个能运用于电力系统谐波测量的有效装置。更多还原

【Abstract】 With the development of power electronic technology, more and more non-linear devices are applied to the power system. Power network harmonic pollution is increasing. So the security of power system is threatened. The operating loss is increasing. The user’s normal work is affected. Therefore, anglicizing and monitoring power system harmonics is very useful to make sure power system running safely.The traditional power quality anglicizing and monitoring systems generally use MCU as code, but an MCU is not fast enough to sample highly and real-time analysis. So the sample data is not enough, and the accuracy of data is low. In recent years, digital signal processor (DSP) is used, so that high-speed sampling, high-speed data storaging and real-time processing of data can be finished perfectly. The DSP uses advanced Harvard architecture. The program memory and data storage has their own bus. It can process program and data at the same time. So it greatly improves the accuracy of harmonic anglicizing. With the method of anglicizing harmonic and electronics developing, more and more harmonic anglicizing equipment is used. Harmonic anglicizing equipments made in abroad are powerful, high precision but expensive. Harmonic anglicizing equipments made at home is opposite. The subject introduces a harmonic anglicizing equipment based on high-speed DSP and FFT, which is high-speed, powerful and cheap.Firstly, variety of harmonic anglicizing algorithm is compared in the subject. The FFT is choosed and studied deeply. Windows and interpolation is used to improve FFT. Secondly, appropriate electronic components are choosed to design a harmonic anglicizing equipment. The paper introduces the hardware of harmonic anglicizing equipment that includes sample module, harmonic anglicizing module, man-machine interface module and serial interface module, etc. Thirdly, the software of harmonic anglicizing equipment is designed, which includes program of sampling data, processing data, communication and upper monitor, etc. Finally, the harmonic anglicizing equipment is used to anglicize harmonic that produced by another equipment. The paper introduces reason of anglicizing error and the way of reduced error is introduced. The result achieves the desired results. The final result is as good as expected.The anglicizing result indicates that the harmonic anglicizing equipment based on DSP is high-speed and high-accuracy. It can be used in power system.更多还原