A Novel Approach for Oil-immersed High Voltage Power Transformer Dissolved Gas Analysis Diagnostic techniques

Abstract

This essay introduces and analyzes the dissolved gases in the insulating oil of power transformers. Analysis of soluble and free gas is one of the most commonly used troubleshooting methods for detecting and evaluating equipment damage. Although the analysis of oil-soluble gases is often complex, it should be expertly processed during maintenance operation. The destruction of the transformer oil will produce some hydrocarbon type gases. The development of this index is based on two examples of traditional evaluation algorithms along with fuzzy logic inference engine. Through simulation process, the results of the initial fractures in the transformer are obtained in two ways by the "Duval Triangle" and "Rogers ratios". In continue, three digit codes containing the fault information are created based on the fuzzy logic inference engine to achieve better results and eliminate ambiguous zones in common methods especially in Duval Triangle method. The proposed method is applied to 80 real transformers to diagnose the fault by analyzing the dissolved oil based on fuzzy logic. The results illustrate the proficiency of this new proposed algorithm. Finally, with utilization of a neural network the new practical inference function is derived to make the algorithm more usable in online condition monitoring.