论文编号:ZD229 论文字数:26914,页数:54
[摘要] 电参数检测技术作为电网自动化控制的基础,在电网安全经济运行方面具有极其重要的作用。本设计实现基于单片机的综合电量变送器测量系统,无论是数据采集还是数据处理都是由单片机控制及完成。硬件部分中设计了交流电压、交流电流输入电路、A/D转换回路、锁相倍频电路、通信接口电路和显示和键盘接口电路。软件部分则是以一周期内采集的数据为检测对象,用数字信号处理技术对采样的数据进行分析,用单片机进行编程,实现交流电参量和直流电参量分析及显示功能。谐波分析则采用了傅立叶算法,可以滤除10次以下的整次谐波,对高频的非整次谐波也有较好的滤波作用。该设计能够保证较高的精度和运算速度,同时具有良好的性能和抗干扰能力,可直接实时检测、控制现场生产过程中强电装置,同时可进行网络通信,对发电检测和用电管理有着重要的作用。
[关键词]电量 智能变送器 检测 单片机 同步采样 算法 串口通信
Examination terminal of low voltage distribution
system’s electricity parameters research
Abstract: The electrical parameter examination technology, as the foundation of the electrical network automation control, plays an extremely vital role in the electrical network security economy movement aspect. The design is realized complex electric parameter transducer based on single chip, no matter of signal sampling or data handling are all fulfilled by single chip. The hardware design have completed altering current and altering voltage input circuit, analog to digital conversion circuit, phase-lock doubling circuit and communication interface, display interface , keyboard circuit. Meanwhile, the part of software has realized the function of the alternating electricity parameter analysis, the directing electricity parameter analysis and the demonstration, which is taking the sampled data in a sampling cycle as the examination object, and carrying on the analysis with the digital signal processing technology to the sampling data, and then programming with single chip. Finally, the harmonic analysis, using the Forier Transform Algorithm, filter the whole time harmonics which are less than 10 order and have a good effect on the filtration of the high frequency non-whole time harmonics. This intelligent transducer has high computation precision and velocity, outstanding capability and the facility of counter interference. This intelligent transducer, realizes the real-time examination and control the directly connecting strong electricity equipment in the local production processing, simultaneously communication through the system network, play an important role in the generate electricity examination and using electricity supervision.
Key words: quantity of electricity, intelligent transducer, measurement, Single chip, synchronized sampling, algorithm, serial communication
目 录
引言 1
1绪论 2
1.1现代电气参数检测技术 2
1.2电参量检测技术在电力系统中的地位和作用 3
1.3研究的目的和意义 3
1.4本文研究的主要内容 4
2系统总体结构和系统功能规划 5
2.1系统功能要求 5
2.2变送器工作原理及发展回顾 5
2.3智能变送器的原理及特点 6
2.4参数检测系统方案论证 7
2.5方案比较 8
2.4.1方案一与方案三比较 8
2.4.2方案二与方案三比较 8
2.6方案的确立 9
3系统硬件部分设计 10
3.1系统原理框图 10
3.2单片机的选择 10
3.3交流电压、交流电流输入电路 10
3.4A/D转换电路 11
3.5A/D转换启动及锁相倍频电路 12
3.6RS-485通讯接口电路原理图 13
3.7显示器接口电路设计 14
3.8键盘接口电路设计 15
3.9电源 16
4系统软件部分设计 17
4.1算法的确定 17
4.1.1直流量算法 17
4.1.1交流量算法 18
4.2综合电量变送器的主体软件框图 21
4.3监控程序模块 22
4.4数据采集和处理模块 23
4.5通信模块 24
4.6软件抗干扰的设计 28
5实验调试及结果分析 29
5.1硬件调试 29
5.1.1测试准备工作 29
5.1.2互感器及I/U转换电路调试 29
5.1.3A/D转换器调试 29
5.1.4锁相倍频电路调试 30
5.2软件调试 30
5.2.1计算程序的调试 30
5.2.2通信调试 30
5.2.3系统校准 30
5.3联机调试 31
5.4测试结果分析 31
5.4.1测试结果 31
5.4.2误差分析 32
总结 34
致谢 35
参考文献 36
附录A芯片MAX180介绍 37
附录B锁相环CD4046介绍 38
附录CRS-485总线介绍 40
附录D程序清单 42
英文文献原文 46
英文文献翻译 48