49. Online Monitoring System of the Grounding Status of Transmission Line Towers

The grounding status of transmission line towers is very important to the security and stability of the transmission line. Nevertheless, it is unfeasible and hard to carry out periodical manual checking of the grounding status in field conditions of the transmission line tower so as to find the grounding fault in time. Aiming at the problems, an online monitoring system in terms of the grounding status of transmission line towers is established. The system is composed of the measure device and the server, in which the measure device is based on the clamp meter method to send the tower grounding status to the server automatically and periodically. The measurement principle is simulated and analyzed in this chapter. Moreover, the prototype is tested in the laboratory environment, and the monitoring system is practically tested on the transmission towers. The result shows that the accuracy of the measure device is no less than 93.96 % when grounding resistance is between 0.3 and 100Ω. Furthermore, the practical application shows that the system is effective and can be useful in the application of lightning protection.