Program development for condition assessment of power transformer in Thailand metropolitan area

This paper presents the developed procedure for condition assessment of power transformer fleet in a utility responsible for supplying electricity in Thailand metropolitan area. The condition assessment is performed by evaluating the quickly-updated test results. The assessment is classified into seven main categories as dissolved gas analysis, oil quality in main tank, oil quality in on-load tap changer, bushing, lightning arrester, visual inspection and thermal scan. The scoring and weighting techniques are applied for condition assessment of each category. The procedure for condition assessment of power transformer components have been further developed as web application software, which displays the results as traffic light indicators. Finally, the developed web application software is now used as a decision support tool for power transformer maintenance in a utility in order to recommend the proper maintenance action.