Electric Transmission Line Insulator Flashover Predictor System

输电线路绝缘子闪络预测系统

• 批准号: 9523267
• 负责人: George Karady
• 金额: $ 10.01万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-10-01 至 1998-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9523267&HistoricalAwards=false
• 关键词: Electric; Transmission; Line; Insulator; Flashover

9523267 Karady Insulator contamination cases frequent flashovers near coastal and industrial areas. This problem occurs in transmission lines as well as in substations. Currently, there are no reliable methods available for monitoring pollution build-up and predicting imminent flashover. The aim of this project is to develop a sensor system that monitors pollution build-up and that would alert operators when there is danger of flashover. Preliminary laboratory studies were performed at ASU and discharge current signatures were analyzed using the Fast Fourier Transform (FFT). Visual manifestations were recorded simultaneously with the current signature. It was found that surface discharges have distinct stages of development. Although the amplitude of current changes continuously, the harmonic content (signature) consistently indicated the status of discharge. It was observed that approaching flashover modifies the harmonic content. These findings suggest that flashover can be predicted by signature analysis of the leakage current. The concept is to select an exposed insulator in each area and monitor the leakage current through the insulator. The leakage current will be digitized and signature analysis will be performed. A change in signature indicates approaching flashover. First, different signature analysis methods will be tested in a laboratory to determine which one produces reliable flashover indication. After the method is identified and tested, a sensor system will be built to perform this signature analysis continuously. It is foreseen that the system will include a broad-band (20Hz-100kHz) currently sensor, a microprocessor and a transmitter. Leakage current will be continuously digitized and 50-100 cycles will be put in temporary storage. The stored data will be analyzed and if no signature change occurs, the data will be discarded. A signature change will trigger a transmitter that will alert an operator. Different levels of ala rm will be used. ***

9523267 Karady绝缘子污染案例频繁发生在沿海和工业区附近的闪络。 这个问题发生在输电线路以及变电站。 目前，没有可靠的方法可用于监测污染积累和预测即将发生的闪络。 该项目的目的是开发一个传感器系统，监测污染的积累，并在有闪络危险时向操作人员发出警报。 在ASU进行了初步的实验室研究，并使用快速傅立叶变换（FFT）分析了放电电流特征。 视觉表现与当前签名同时记录。 结果发现，表面放电有不同的发展阶段。 虽然电流的幅值不断变化，但谐波含量（特征）始终指示放电状态。 据观察，接近闪络修改谐波含量。 这些研究结果表明，闪络可以预测的泄漏电流的签名分析。 其概念是在每个区域选择一个暴露的绝缘体，并监测通过绝缘体的泄漏电流。 漏电流将被数字化，并将进行签名分析。 信号的变化表明接近闪络。 首先，将在实验室中测试不同的特征分析方法，以确定哪一种产生可靠的闪络指示。 在确定和测试该方法后，将建立一个传感器系统，以持续进行这种特征分析。 可以预见，该系统将包括宽带（20 Hz-100 kHz）电流传感器，微处理器和发射机。 漏电流将被连续数字化，并将50-100个周期置于临时存储中。 将对存储的数据进行分析，如果未发生签名更改，则将丢弃数据。 信号的变化会触发一个发射器，向操作员发出警报。 将使用不同水平的alarm。 ***