Analysis and reduction of external effective welding failures in high voltage insulators

Due to the increase in the use of electrical energy, the voltage levels in the transmission and distribution networks also increase. Therefore, it is necessary to implement both economic and efficient solutions in order to isolate the equipment and current-carrying conductors used in the networks from each other and from other components of the system. In our country, which is in need of increasing energy needs as in all over the world, it is vital to minimize energy losses during the production, transmission and distribution stages of energy. High-voltage insulators are expected to make an effective, continuous and safe insulation. However, due to the fact that they are exposed to many electrical, thermal, mechanical and environmental factors under operating conditions, some problems arise in terms of insulation. In this thesis, researches have been carried out on analyzing the failures seen in high voltage switchgear equipments and insulators, also reducing these failures. In this context, the electrical and mechanical different parts of the porcelain outer surface, undertake the installation of electrical equipment and insulators. Failures have been analyzed that occurring to both the internal structure of the system and environmental factors. In the analyzes, it has been determined that the type of 'contamination failure' type which is caused by pollution and meteorological effects on the porcelain outer surfaces of the switchgear and insulators and which cause serious failures or even interruptions in the transmission systems are important. For this reason, the stages of formation of the pollution skipping failure has been scrutinized./ For this reason, the stages of formation of the pollution skipping failure are examined. Within the scope of the study, it was determined that the coating of porcelain insulator surfaces with protective material would be the most effective solution in order to reduce the malfunction. The surface of the porcelain insulator which is modeled by using finite element method, In cases where the protective material is uncoated and coated, pollution factors are added. The results for both cases were compared. In Turkey national transmission network for material coating application a down transformers for high voltage switchyard located coating of porcelain outer surface with equipment and at the same switchyard connected to the silicon insulators work in the energy VI transmission line was investigated. As a result of the investigations, it has been determined that the number of failures in the transmission system has decreased significantly. This study showed that in high voltage equipment with porcelain outer surfaces, malfunctions caused by external factors can be reduced by the method of coating with protective material and stability can be achieved in the systems.