雷电流全参数及避雷器状态在线监测研究

为给分析判断雷击线路杆塔号、雷击形式及实现快速定位提供充分的依据,研究了一种雷击输电线路和避雷针的雷电流全参数在线监测系统,采用罗氏电流传感器和前置机,配合GPRS公共平台远端传输接收数据,首次得到了雷击杆塔的电流波形、幅值、极性和雷击点位置。此外,还研究了线路用带间隙避雷器的运行寿命和配网避雷器运行状态的在线监测指示器,其中采用大电流通过次数的计数方法以确定带间隙避雷器的剩余寿命,设计的状态指示器的起始动作电流<100A,大电流时能可靠动作,告警和吊牌复位机构满足可靠性要求。配网避雷器采用阻性电流分量作为检测对象,当检测到的阻性电流达到设定阈值时,装置将自动发出双重故障指示。在多个变电站实际运行的结果表明:该装置动作可靠、标识明确、使用方便,减少了检修和停电导致的经济损失,提高了配电网的供电可靠性。

Research on Whole Parameters of Lightning Current Waveform and On-line Monitoring of Arresters

The basic composition principle and application of an on-line monitoring system are introduced.By the uses of a Roche electronic current sensor and an advanced signal-processor,and receiving data from remote commission of GPRS public platform,this system firstly records the waveform parameters,amplitude,polarity of the lightning current and position that lightning strikes.On the basis of the recorded data,line towers suffering from lightning stroke and forms of lightning are analyzed and judged.Furthermore,the system involves two kinds of on-line indicators.One can monitor life time of arresters with series gap applied in transmission lines by the way of counting the times of lightning currents release.This indicator,with the less than 100A start action current,operates reliably when large amplitude lightning current releases,and is still reliable on alarm and drop mechanisms.Aother is to monitor operation conditions of arresters of distribution lines by monitoring the object of resistive of leakage current,once the detected object reaches pre-installed threshold,the indicator will automatically give dual breakdown instructions.The practical applications in several substations show that the indicator has reliable action and clear mark,and is convenient to use.Therefore,the indicators decrease financial cost due to undesirable maintenance outage and improve the reliability of power supply.