Case Study: Reliability Enhancement of Power Transformer using DGA

Power system reliability is the main concern for utilities these days as it leads to economic benefits and customer satisfaction. At various levels of power systems, i.e. generation, transmission and distribution, the different methods have been developed to assess reliability and various techniques have been improvised to enhance the same. Most of the reliability improvement techniques require some initial expenses or reconfiguration of existing system. In this paper, power transformer, an important asset of power systems is taken into consideration to increase the reliability. In consideration to this, primary maintenance tool i.e. Dissolved Gas Analysis (DGA) is taken into account for power reliability enhancement. DGA is one of the promising method in finding out the indicative threat to power transformer and thus helps to define the approximately correct schedule to shut down the transformer. The paper furnishes the facts as the case studies were carried out at three differently located substations in India whereby the various electrical routine tests were replaced by DGA in order to successfully reduce the outage hours and eventually enhance the power system reliability.