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  1. TRANSFORMER Presented By Deepak Patel
  2.  Introduction  Working Principle  Construction Types of transformer  Ideal Transformer  Losses in Transformer  Efficiency  Voltage Regulation Contents
  3. Transformer is an static device that transfer electric power at same frequency usually from one voltage level to another. In brief, 1. Transfers electric power from one circuit to another. 2. It does so without a change of frequency. 3. It accomplishes this by electromagnetic induction 4. The two electric circuits are in mutual inductive influence. Transformers are ubiquitous device. They are used to either step-up the AC voltage or step down it. Introduction
  4. Why should we do this voltage transformation? By increasing the transmission voltage.  Power transfer capability of line increased.  Power loss in transmission line is reduced.  Area of cross section and volume of conductor is reduced.
  5. Working Principle • It is based on principle of Electromagnetic Induction. • According to this principle, a varying magnetic flux associated with a loop will induce an electromotive force across it.
  6. • This magnetic flux can be effectively linked to a secondary winding with the help of a core made up of a ferromagnetic material. • This fluctuating magnetic field will induce an E.M.F in the secondary coils due to electromagnetic induction.
  7. • Since the turns are arranged in a series, the net E.M.F induced across the winding will be sum of the individual E.M.Fs induced in each turn. • As the same magnetic flux is passing through the primary and secondary coils the EMF per turn for both the primary and secondary coils will be the same • The induced E.M.F at the secondary coil is expressed as follows
  8. Emf equation of transformer
  9. Construction of Transformer Basically a transformer consists of o two inductive windings o a laminated steel core A transformer may also consist of o Container for winding and core assembly (called as tank) o Bushings to take our the terminals o Oil Conservator
  10. Types of Transformers There are two basic Types of Transformers o Single Phase Transformer o Three Phase Transformer Types of Transformers w.r.t Cores o Core Type Transformer o Shell Type Transformer Types of Transformer w.r.t uses o Power Transformer o Distribution Transformer o Instrument Transformer
  11. Ideal Transformer An ideal transformer is an imaginary transformer which has o no copper losses (no winding resistance) o no iron loss in core o no leakage flux o Infinite permeability of the core o 100% efficiency
  12. Phasor diagram of ideal Transformer Without Load With Load
  13. Losses in Transformer
  14. Efficiency of Transformer
  15. Condition for maximum efficiency
  16. All Day Efficiency of Transformer All day efficiency of a transformer is always less than ordinary efficiency of it.
  17. Voltage Regulation The change in magnitude of secondary(terminal) voltage when full load at specified power factor is thrown off i.e. reduced to no load with primary voltage held constant, as percentage of rated load terminal voltage. Voltage Regulation is a figure of merit of a transformer and its low value is desirable. Regulation can be reduced by reducing the per unit impedance.
  18. Effect of power factor on voltage regulation