Experimental Study on Ultrasonic Detection Method of Ice Thickness for 10 kV Overhead Transmission Lines

Transmission-line icing is a serious threat to the security safe and stable operation of power systems. The icing monitoring of transmission lines is of significance for the prevention of freezing disasters in power systems. However, the lack of effective ice detection methods has brought great trouble to the safe operation of 10 kV overhead transmission lines in freezing weather. To tackle this problem, a method for detecting ice thickness for 10 kV overhead transmission lines based on an ultrasonic detecting technique is proposed in this article, in which the distance from the ultrasonic sensor to the line changed by transmission lines ice-coating and the distance difference before and after ice-coating detected by ultrasonic being the ice thickness. An ultrasonic detection platform for ice thickness on the steel rod to simulate the line icing is established. The calibration experiment with the effect of distance, temperature, and wind velocity on the ultrasonic is carried out, and the experiment with ice thickness on the steel rod detected by the ultrasonic is carried out. Furthermore, the effect of ice shape on the detection is studied, and the reason for the large error is analyzed when the number of bulges on the ice surface is large. The results show that the relative error of ice thickness obtained by the method proposed in this article is less than 10% under conditions of uniform ice and relatively smooth ice surface, compared with vernier caliper measurements. An improved method for ice thickness detection using the trough time as the ultrasonic echo signal time is proposed when the number of bulges on the ice surface is large, and the relative error value of the improved method is verified to be less than 5%.