Critical comparison of the measurement accuracy of DGA techniques for the timely detection of emerging faults

In the context of modern energy engineering, power transformers constitute one of the most critical parts, as they ensure the efficient conversion and distribution of electrical energy throughout the power grid. The reliability of transformers, is fundamental for the safe and continuous operation of the network, and the timely detection and diagnosis of potential faults is essential. This paper focuses on the Dissolved Gas Analysis (DGA) method, as a primary tool for analyzing and detecting emerging faults in transformers. Specifically, DGA techniques are based on the principle that various faults within the transformer lead to the production of specific gases, which are dissolved in the oil used for insulation and cooling of the u nit. Analyzing the composition and concentration of these gases can provide valuable information about the nature and severity of the faults. Additionally, in this paper an analysis and comparison is conducted between the offline DGA monitoring and online DGA monitoring used for analyzing transformer gases, focusing on the accuracy of each technique.