Tracking Wheel Test Research Articles

Fractal Analysis for Classification of Electrical Testing of Polymer High Voltage Insulators

Silicone insulating rubber is an elastomer widely used in industry, especially in the manufacturing of insulators for power lines. This material ages or degrades due to pollution and environmental factors such as UV, rain, and temperature. In order to evaluate its resistance to tracking and erosion, international standards like IEC (International Electrotechnical Commission) include testing for insulating materials such as the inclined plane test (IPT) or tracking wheel test. However, the results from these tests are sometimes subjective and inconclusive. Thus, objective ways of evaluating insulating materials are needed. In this paper Fractal Analysis is used to classify the results of electrical testing in sheds proceeding of commercial high voltage insulators through the inclined plane test. The results show that Fractal Analysis constitutes a more objective way to classify the electrical strength of high voltage insulators.

Fractal Analysis for Classification of Electrical Testing of Polymer High Voltage Insulators

Silicone insulating rubber is an elastomer widely used in industry, especially in the manufacturing of insulators for power lines. This material ages or degrades due to pollution and environmental factors such as UV, rain, and temperature. In order to evaluate its resistance to tracking and erosion, international standards like IEC (International Electrotechnical Commission) include testing for insulating materials such as the inclined plane test (IPT) or tracking wheel test. However, the results from these tests are sometimes subjective and inconclusive. Thus, objective ways of evaluating insulating materials are needed. In this paper Fractal Analysis is used to classify the results of electrical testing in sheds proceeding of commercial high voltage insulators through the inclined plane test. The results show that Fractal Analysis constitutes a more objective way to classify the electrical strength of high voltage insulators.

Investigation on tracking wheel test of large-diameter composite insulators under AC voltage

The tracking wheel test specified in IEC/TR 62730:2012 provides a method that can be used to evaluate the resistance of composite insulators to tracking and erosion for rejecting inadequate materials or designs. Currently, most of the tests have been conducted on composite line insulators and some other insulator types with relatively small diameters. As the usage of large-diameter composite insulators, such as composite station insulators and composite cross-arms, increases rapidly, it is urgent to investigate if the tracking wheel test method is also suitable for their evaluation. In this study, a tracking wheel device for composite insulators with different diameters, designed and constructed in accordance with the IEC standard, is presented. The relationships between the leakage current and NaCl content as well as the average diameter of the specimen are investigated. It is shown that the test parameters specified in the IEC standard are not suitable for specimens of relatively large diameters. Accordingly, a relevant modification of test parameters has been introduced and verified, showing similar phenomena during the verified test as those observed during previous studies on composite line insulators. It is thus claimed that the modified test procedure is feasible for being applied on large-diameter insulators.

A study of composite insulator aging using the tracking wheel test

In this paper, silicone rubber (SR) insulators are investigated as to the aging behavior at different aging time in tracking wheel. Sampling was done every 200h till 2000h. Thermo Gravimetric Analysis (TGA), Fourier Transform Inferred Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), contact angle measurement, Energy Dispersive X ray scattering (EDX), mechanical and electrical tests were carried out for these purpose. The correlation coefficient of 0.9 proved an acceptable relation between migration of smaller size low molecular weight molecules (SLMWs) and contact angle. TGA and extraction testes results showed SLMW are almost 15% of total LMWs and responsible for recovery of hydrophobicity. Also TGA results demonstrated that after 2000h accelerated aging, thermal stability (potential thermal-resistant property) of the PDMS polymer decreases about 10%. ATR-FTIR analysis results showed the rate of Si-O-Si peak changes was higher than vSi-C and the vOH peak decreases by the 50%. The surface hardness increased about 20% with increasing aging time to 2000h. An average reduction of 30% and 25% in the tensile strength and strain at break were found with respect to the virgin sample aged. Increasing aging time increases leakage current from 50 to 500 (μA) that still is lower than 1 mA so means there is no critical degradation.

계면활성제가 첨가된 염수용액에 따른 폴리머 애자의 트래킹 성능 평가

Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. Polymer material is also investigated it`s tracking resistance by adding surface active agent in IEC 587. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination, STRI guide and thermal image camera.

Aging of distribution composite insulators under environmental and electrical stresses

Seven types of commercially available distribution composite insulators with sheds made of EPR (ethylene-propylene rubber) or epoxy resin were subjected to various functional aging tests recommended by the IEC or the IEEE. The influence of ultraviolet (UV) radiation on the aging of the shed materials was also evaluated. The usefulness of the various aging and diagnostic tests is discussed, and a modification of the recommended test procedures is proposed in order to improve the evaluation of the long-term performances of these insulators. The aging test methods and the acceptance criteria proposed by the IEC and the IEEE are not sufficient to discriminate between the seven insulator types tested. Extending the aging test duration to 2500 h and using the IEC water immersion test as a diagnostic tool brought out differences in the performances of the insulators. No significant synergism was found to exist between the UV radiation and the stresses caused by the salt fog test or the tracking wheel test when they are applied sequentially. >