考虑外表面污秽影响的避雷器在线监测技术

On-line Monitoring Technology for Arresters ConsideringAffection of Filth on Their External Surface

避雷器是防止电力设备受到雷击损害的重要设备,其运行环境比较恶劣,原有的在线监测方法不考虑避雷器外表面污秽对监测效果的影响,测量精度低。基于避雷器外表面污秽的情况,设计了一种氧化锌避雷器在线监测装置。装置采用谐波分析法和双“AT”法结合的方法监测避雷器泄漏电流,并通过光纤传感器监测避雷器外表面的污秽度,通过污秽度修正泄漏电流,提高装置的测量精度。此外,通过遗传算法优化神经网络,使光纤传感器测量污秽度可以更准确地计算出等值盐密。

Arrester is an important device for preventing power equipment from lightning damage and it operates in quite severe environment.Existing on-line monitoring methods take no account of the affection of the filth on the external surface of the arrester upon monitoring effect,resulting in low measurement accuracy.An on-line monitoring device was designed for the zinc oxide arrester under consideration of filth on the external surface.Leakage current of the arrester was monitored in a combination of harmonic analysis method and double“AT”method.Contamination severity of the external surface of the arrester was monitored by an optical fiber sensor,and the leakage current was corrected through contamination severity so as to raise measurement accuracy of the device.Furthermore,if the neural network was optimized through genetic algorithm,equivalent salt deposit density could be calculated more accurately through contamination severity measured by the optical fiber sensor.