A Comparative Study of Abnormal Heating Composite Insulators

Abstract

The abnormal heating of composite insulators on transmission lines frequently occurs, seriously threatening the power grid’s safe and stable operation. For different types of abnormal heating composite insulators, undifferentiated replacement wastes a lot of labor and material resources. This study explores the abnormal heating composite insulators under different environmental humidity and wind speed conditions. The heating and discharge of composite insulators are observed, and the heating range, heating shape, and temperature rise (ΔT) are analyzed. The abnormal heating of the sheath-aging composite insulator is related to the aging of the silicone rubber and the environmental humidity. The partial discharge caused by the core rod’s defect is the primary source of the temperature rise in the decay-like insulator. The heating range of the contaminated insulator is connected to the environmental humidity, and the ΔT increases with the salt density. The ΔT and heating range of the three types of abnormal heating increase with the ambient humidity. The heating phenomenon under low humidity is an important characteristic that distinguishes decay-like and contaminated insulators from sheath-aging insulators. Therefore, the on-site infrared inspection should be carried out in sunny and windless weather to prevent the impact of high humidity and wind speed on infrared temperature measurement.

Study on the Mechanism Effect of Bending Loads on the Decay-like Degradation of Composite Insulator GFRP Core Rod

“…Different composite insulator samples subected to varying alternating load cycles were tested for electrical temperature rise. To make the heating phenomenon more pronounced, the composite insulator samples were placed in a constant temperature and humidity chamber at 20 • C and 75% RH for 150 h before the test to ensure saturated moisture absorption [25,26]. Afterward, a 64 kV, 50 Hz AC voltage was applied to the high-voltage end fittings of the composite insulator while grounding the low-voltage end fittings.…”

“…were tested for electrical temperature rise. To make the heating phenomenon m nounced, the composite insulator samples were placed in a constant temperature midity chamber at 20 °C and 75% RH for 150 h before the test to ensure saturated absorption [25,26]. Afterward, a 64 kV, 50 Hz AC voltage was applied to the high end fi ings of the composite insulator while grounding the low-voltage end fi i hour after applying the AC voltage, the temperature rise images of the composit tor were recorded using a FLIR T1040 handheld thermal imaging camera prod Teledyne FLIR in Wilsonville, OR, USA.…”