Category: Transformers Articles

Efficiency is a factor that defines the performance of any device or equipment. Generally, it is specified as the ratio of the output obtained to the input fed to a device. It suggests to what extent a device is utilized. In an overhead transmission line (OHTL) insulator, a number of insulator discs are arranged in a string in accordance with the operating voltage. The lowest disc or unit which is i near the power conductor experiences maximum stress or it is fully utilized. But, as we move towards the top…

Power Transformer Cooling Methods The transformers get heated due to iron and copper looses occurring in them. It is necessary to dissipate this heat so that the temperature of the windings is kept below the value at which the insulation begins to deteriorate. The cooling of transformer is more difficult than that of rotating machines because the rotating machines create a turbulent airflow which assists in removing the heat generated due to losses. Luckily the losses in transformers are comparatively small. Nevertheless the elaborate cooling arrangements have been devised to deal with the whole range…

Transformer EMF Equation In this article the amount of emf induced in the secondary winding due to the current supplied to the primary winding can be calculated by EMF equation of the transformer.This is very essential in the designing process of any transformer.Because the amount of emf induced due to mutual induction also depends on the number of turns in the coil.Transformer emf equation gives the output voltage value so that we can design a transformer as per our requirements. Derivation : EMF Equation of Transformer Let, N1 = Number of turns in the primary winding…

We conduct open circuit and short circuit test on single phase transformer to determine the efficiency and regulation of a transformer on any load condition and at any power factor.Open circuit & short circuit test are also called as OC test & SC test on the transformer.This method of finding the parameters of a transformer is called as an indirect loading method. Open Circuit(OC) and Short Circuit(SC) Test on Transformer What is the need for OC & SC test on transformers? Open circuit test and short circuit test on the…

Sumpner’s Test Or Back-To-Back Test On Transformer Sumpner’s test provides data for finding the regulation, efficiency and heating under load conditions and is employed only when two similar transformers are available.The O.C. and S.C. tests give us the equivalent circuit parameters but can not give heating information under various load conditions.The Sumpner’s test requires two identical transformers.One transformer is loaded on the other and both are connected to supply. The power taken from the supply is that necessary for supplying the losses of both transformers and the negligibly small loss…

The transformers are connected in parallel when the load on them is more than the rating of the individual transformers. Before going to discuss parallel operation of single phase transformers  A small question for you all that is ‘why the parallel operation of transformers is required?’. The answer is simple we have some advantages over operating single transformer units so we go for parallel operation of transformers. Advantages of Parallel Operation of Transformers Parallel operation is nothing but connecting primary windings of two or more transformers to supply and secondary windings to common loads.To supply more than…