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Slide 1: General idea about the transformers Do you know how current gets transformed to your cities or state, it is through the help of transformers. Transformers are the storage device for electricity that transforms electric circuit from one to other and many industries depend upon the transformer for their industrial use. It was discovered by Michael Faraday and Joseph Henry in 1831 and the first credit goes to Faraday for his experiments. It has two windings and it is based on two principles such as, it can produce magnetic filed and the changing magnetic field can induce voltage across the ends of the coil. The transformers are classified into different types such as power transformer, pulse transformer, instrument transformer, audio transformer, RF transformer and home made transformer. It is classified into different ways by its power capacity, frequency range, voltage class, cooling type, application, purpose and by its winding turns. It is constructed using air cores, toroidal cores, solid cores and laminated steel cores. According to its method of mounting it is classified into pole and platform, subway, vault and special and it is classified into single and poly-phase by its number of phases. According to its purpose it is classified into Current and Constant current, variable and constant voltage. Transformer dissipates more heat energy and it needs to be cooled in an efficient way, otherwise it would destroy the insulation of the transformer. The cooling of transformers is done using different methods such as liquid immersed self cooled, self air cooled, air blast cooled, self air cooled and oil immersed cooled. In transformers the oil plays a major role with some functions such as insulate the coil from each other and from the core, and conduct heat from the coils and core to some other cooler surfaces. Many oils have been used in the transformers, but mineral oil is mostly used as transformer oil and the oil should not give off gases and it subjected to very little evaporation. Let us see an overview on some important types of transformers and their details. Current transformer is used to change the current of the system and the primary and secondary
Slide 2: windings used to change with the value of the current of the system. With the help of current transformer you can measure the voltage drop across a known resistor and it is commonly used in electricity meters. Be cautious that, current transformer is not removed from its load while current is in motion. These custom current transformers are the instrument transformers which used to supply a reduced value of current to relays meters and other instruments. High voltage transformer steps up the primary voltage to a very high voltage and these can be boosted to higher voltages by the use of capacitor and diode and they accurately measure the voltage supplied. Fly back transformer is used to generate high transformer voltage at a high frequency and it is also called as line output transformer. It is used in the television, Computer monitors and other high voltage devices and it not only transfers energy, but also stores energy for some considerable switching period.