氧化锌避雷器状态在线监测系统设计

发布时间：2018-07-29 21:21

【摘要】：氧化锌避雷器作为过电压保护装置,长期承受电网工频电压会产生老化受潮等问题,需要对其进行定期在线状态监测,当电网电压频率发生扰动时,传统避雷器在线监测方法存在频谱泄漏和栅栏效应,使得测量结果产生较大偏差。针对这一问题,提出了一种将相位测量法与加窗插值谐波分析法相结合的测量泄漏电流新方法。通过对经典余弦窗的仿真研究,选取了布莱克曼窗作为抑制频谱泄漏的余弦窗,同时将余弦窗与双峰插值算法相结合,通过仿真验证了布莱克曼窗双峰插值算法的优越性和有效性,并通过仿真选取了最优的硬件采样参数。结合国内避雷器分布式监测的现状,本文设计了基于RS485总线的氧化锌避雷器状态在线监测系统,设计的监测系统包括前端避雷监测器、中端数据采集器以及后台现场监控中心上位机。监测器以C8051F310增强型单片机为核心,能实现泄漏全电流、基波电流、三次谐波电流、阻性峰值电流以及容性峰值电流的测量。采集器以C8051F020单片机为核心,主要实现了485网络的扩展以及监测器数据的采集与传输工作。上位机设计包括了现场调试软件和现场监测软件,能实现监测器在线调试以及避雷器数据动态监测、历史查询、故障定位等功能。本文设计的避雷器在线监测系统在11KV避雷器测试中运行良好,测试结果表明本系统设计准确,能稳定可靠运行,有效监测避雷器状态。
[Abstract]:Zinc oxide arrester, as an overvoltage protection device, will cause aging and damp under power frequency voltage for a long time, so it needs to be monitored on line periodically, when the voltage frequency of power grid is disturbed, There are spectral leakage and fencing effect in the traditional on-line monitoring method of arrester, which results in a large deviation of measurement results. To solve this problem, a new method for measuring leakage current is proposed, which combines the phase measurement method with the windowed interpolation harmonic analysis method. Based on the simulation of the classical cosine window, the Blackman window is selected as the cosine window to suppress the spectrum leakage, and the cosine window is combined with the bimodal interpolation algorithm. The superiority and effectiveness of the Blackman window bimodal interpolation algorithm are verified by simulation, and the optimal hardware sampling parameters are selected by simulation. Combined with the present situation of distributed monitoring of lightning arresters in China, an on-line monitoring system of zinc oxide arresters based on RS485 bus is designed in this paper. The monitoring system includes front-end lightning arresters. The middle end data collector and the upper computer of the background field monitoring center. The core of the monitor is C8051F310 enhanced single chip computer, which can measure the leakage full current, the fundamental current, the third harmonic current, the resistance peak current and the capacitive peak current. The C8051F020 MCU is the core of the collector, which mainly realizes the expansion of 485 network and the acquisition and transmission of monitor data. The design of upper computer includes field debugging software and field monitoring software, which can realize on-line debugging of the monitor, dynamic monitoring of lightning arrester data, history query, fault location and so on. The on-line monitoring system of the arrester designed in this paper runs well in the 11KV arrester test. The test results show that the system is accurate, stable and reliable, and can effectively monitor the state of the arrester.
【学位授予单位】：南京信息工程大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM862

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