Evaluating the contamination level of polluted insulators based on the characteristics of leakage current

Abstract

SUMMARYEffective prediction of the contamination level of insulators is an important approach to the prevention of pollution flashover accidents, and the leakage current (LC) is an efficient factor to analyze and detect the contamination level of insulators. In order to predict how severe the contamination level of insulators is and prevent pollution flashover accidents, firstly, some artificial pollution tests have been investigated under different contamination levels, relative humidity (RH), and ambient temperature (T). Secondly, based on the experimental data, the three characteristics of LC, namely the maximum pulse amplitude (I h ), the energy ratio (K), and the energy (E), have been extracted. They reflect jointly the LC from different perspectives. Thirdly, the variation laws between the three characteristics and the contamination level, RH and T, have been obtained. Fourthly, the prediction of the contamination level by using least squares support vector machine (LS-SVM) model has been presented, in which the three characteristics, RH and T are used as the inputs of model, and the contamination level is used as the output of model. Finally, this model has been verified with the test data obtained in the artificial climate chamber, and the prediction results are consistent with the test results. Therefore, the LS-SVM model is acceptable to predict the contamination level of insulators and is of significance for the prevention of pollution flashover accidents.

Application of UHF-based partial discharge detection and analysis of tar-polluted insulator of a wet ESP unit

“…Each current pulse of a discharge has a unique rise time and carries a unique amount of charge that can be gathered by measuring indirectly or directly the cur rent pulse in an electrical circuit [28][29][30]. Furthermore, each discharge event causes in parallel emissions of sound waves and photons, providing an alternative possibility to gather the information by wideband-, acoustic-, optical-and UHF-based PD measurement procedures [29][30][31][32][33][34][35][36]. These PD events appear as fast current pulses of rise time in nanoseconds and comprise tremendous information which can be analyzed using conventional and non-conventional PD methods.…”

“…The currently available diagnostic test methods may provide altogether the possibility of an early detection of the surface degradation of the insulator [6,10,[19][20][21][22][23][32][33][34][35]. Naturally, a clear discrimination between wet and dry surface deposition becomes possible [6,19,20].…”

Hybrid K Based Influential Parameter Determination and Design Optimization of 220 kV High Voltage Insulator

“…The insulator contour design is of prime importance as well, in order to have minimal tangential force on the insulator [6]. Genetic algorithm is used for contour optimization of a suspension type insulator with the aim to Manuscript received 5 December, 2018; accepted 8 April, 2019. minimize the electrical stress [7], [8]. For operation of composite insulators the electric stress on the surface of the insulator is a major factor [9], [10].…”

Reconsidering insulation coordination and simulation under the effect of pollution due to climate change

“…Insulators of transmission lines crossing specific areas can be subject to pollution. The type of pollution and duration of exposure to it are among other factors affecting the system insulation . Pollution of the external surface of insulators including industrial and coastal insulators is the major cause of electrical discharge of insulators in common power systems.…”