10kV避雷器在线监测装置研制

Design of On-line Monitoring Device for MOA Used in 10kV Distribution Network

由于价格低廉,事故影响较小,10 kV线路避雷器的监测一直被忽略,但此类避雷器使用量大、分布广、故障点查找困难,为此研制了一种简单实用的10 kV线路避雷器在线监测装置。该装置采用阻性电流分量作为检测对象,当阻性电流达到设定阈值时,发光二级管闪亮,阻性电流达到损坏值时,装置自动掉牌指示;装置还备有过电压和误动防护措施。现场实际运行状况表明,该装置可实现配网避雷器的在线监测,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。

Due to the low cost and small impact on the distributed network, the monitor of metallic oxide arrester （MOA） used in 10kV distribution network is always ignored. However, with a massive application, wide distribution, and difficulties in fault location, it is necessary to development on line monitoring device of MOA used in 10kV distribution network. Based on the present monitoring condition of MOA in China, a kind of practical on-line monitoring device for MOA used in 10kV distribution network was conducted. Because the thermal degradation of MOA is mainly brought about by the watt loss of resistive current, this device is oriented to the resistive component of leakage current, and the reliability and precision of this means is remarkably improved compared to the method based on total current detecting. When the detected resistive component of leakage current reaches the setting threshold, the device will give a reliable sign of both mechanic motion and luminescence indicating the failure. In this device, protective measures against over-voltage and mis-operation are taken into account as well. This device has been applied in the site of 10 kV distribution network. From the site operation results, it can be illuminated that this device can effectively realize the on-line monitoring of MOA used in 10kV distribution network, decrease the economic loss caused by overhauls and black-outs, and improve the power-supply reliability of distribution network.