Estimation of optimum load and thermal response for Oil-Natural-Air- Natural cooling type power transformer

Abstract

This paper described the estimation of optimum load and thermal response for the Oilnatural Air-natural (ONAN) cooling type power transformer with installed load capacity of 30MVA in Sarawak, Malaysia. The estimation optimum load capacity is based on the nameplate rating, standard design of the existing transformer and factory acceptance test report (FAT). This involved loss of life and transformer thermal response such as hotspot temperature, top-oil temperature, winding temperature and ambient temperature. By using the existing cyclic load of this transformer, the risk condition of the transformer could be prevented since capacity load could be estimated. The algorithms of this project were based on IEEE standard and IEC loading guide for oil-immersed power transformer.