Evaluation and prediction of contamination level in coastal region insulators based on leakage current characteristics

Abstract

The paper addresses the serious issue on insulators owing to partial discharge and flashover resulted from severe NaCl salt contaminant accumulation on transmission lines insulators located near the coastal areas. Disc type insulators such as porcelain and glass were tested at various NaCl salt pollution level in an artificial fog chamber according to IEC60S07 standard. The leakage currents associated with insulator types were recorded continuously at equal operating conditions (voltage, temperature and press ure). The statistical data of the leakage current such as the mean value (llll ean), maximum value (llll ax) and standard deviation (0') are considered. The recorded leakage currents are employed in Neural Network model as an input and using Feed Forward Back Propagation Network, the resultant contamination severity is predicted. This model is suitable to predict the Equivalent Salt Deposit Density (ESDD). The Neural Network Model is used to determine (predict) the intensity of leakage current (in mA) during security stage «SOmA) in the course of inception voltage.

State of the Art on High Voltage Metrology: Past, Present and Future

“…Some of these methods are carried out in laboratories and others are performed on-line under operating voltage and environmental conditions. This method is commonly used in transmission lines which are subjected to extreme and varying pollution conditions [46]. The controlled fog chamber is one of the laboratories measuring approaches for leakage current [14].…”

Studies the effect of Equivalent Salt Deposit Density on leakage current and flashover voltage of artificially contaminated disc insulators

“…This five weather factors, humidity pressure, temperature, velocity of the wind and rain are considered during experiment. In this paper ESDD is calculated by the method followed in these literatures [2][3]. Due to the temperature raises on the surface dry band build gradually.…”

“…Contamination caused insulator flashover has been studied by many researchers in the recent years [1][2][3][4][5][6][7][8]. A large percentage of outages in distribution and transmission lines, especially in polluted areas, are related to insulators flashovers.…”

“…The field level pollution behaviour on insulator surface in overhead lines are investigated using artificial pollution testing [4], that determines the dielectric strength of insulator in polluted condition. The Equivalent Salt Deposit Density (ESDD), the surface conductance, the leakage current, air pollution measurements, optical measurements, and the non soluble deposit density (NSDD) are the most widely used method for condition monitoring of high voltage insulator [1][2][3][4]. The leakage current, collected at the ground end of the insulator which is mainly driven by the source voltage, provides much useful information out of many parameters describing the state of a contaminated insulator.…”

Surface resistance of ESD-protected worksurfaces—measurement, modelling and estimation considerations

“…Earlier experience has already revealed that dust settling on the worksurface, in combination with humidity and temperature of ambient air, has impact on the resistance of ESD-protected worksurfaces. Therefore, it is worth examining how these conditions are represented in literature in other domains [19], [20]. Relevant in this context are results regarding particulate matter, aerosols and settling of dust [21]- [23] which reveal much regarding expected fluctuations of dust density (even though, care must be taken regarding the specific composition and ratio of mineral particles, cellulose and skin fragments which differ in outdoor environments and closed airspaces of manufacturing facilities).…”