This paper presents an artificial neural network (ANN) based scheme for fault identification in power transformer protection. The proposed scheme is featured by the application of ANN to identifying system patterns, the unique choice of harmonics of positive sequence differential currents as ANN inputs, the effective handling of current transformer (CT) saturation with an ANN based approach, an...

Dissolved gas analysis (DGA) of transformer oil is one of the most effective power transformer condition monitoring tools. There are many interpretation techniques for DGA results however all current techniques rely on personnel experience more than analytical formulation. As a result, the current techniques do not necessarily lead to the same conclusion for the same oil sample. A significant n...

Power transformers prove to be a vital element or tool in electrical power supply and transmission system. They are capital intensive units and need to be monitored for faults. Faults in transformers leading to their failure are repugnant. Thus, there is a need to detect such faults at an initial level. This paper aims to detect, diagnose the nature and cause of mechanical faults, their identit...

Dissolved Gas Analysis is one of the most useful method to detect incipient faults in transformer. Amongst the conventional DGA methods, IEC three ratio method is widely used. One of the disadvantages in its present form is that a significant number of DGA results inservice fall outside the existing IEC codes and cannot be diagnosed. To overcome this limitation, additional eighteen new combinat...

Power transformers are protected by different relays that operate independently. Malfunction of each relay has a major role in reducing the reliability of the protection system. In order to mitigate the main drawbacks of the power transformer relays, an overall protection scheme is presented in this paper. This scheme proposes a novel multi criterion algorithm using decision-making based on fuz...

Dissolved Gas Analysis (DGA) is one of the most common techniques to detect the incipient faults in the oil-filled power transformers. In this paper, a new approach of DGA technique is proposed to overcome the conflict that takes place in the traditional interpretation techniques for transformer fault diagnosis. The new approach is based on the analysis of 386 dissolved gas samples data set tha...

Dissolved Gas Analysis is an important analysis for fault diagnosis and condition monitoring of power transformer. The various technique such as conventional methods, Artificial Intelligence, Artificial Neural network, Fuzzy Expert system, Genetic algorithm etc can be used to increase the efficiency and accuracy of diagnostics system. Failures of power transformer can cause malfunction of syste...

This paper presents a new approach to power transformer differential protection based on HS-transform and SVM (support vector machine). Here, HS-transform is used to generate frequency contours from samples of differential current and parseval’s theorem is used to extract the features like energy and standard deviation. Subsequently these features are used as inputs to SVM for fault classificat...