Knowledge is power essay

Introduction of Efficiency of Transformer Transformers form the most important link between supply systems and load. Transformer’s efficiency directly affects its performance and aging. The transformer’s efficiency, in general, is in the range of 95 – 99 %. For large power transformers with very low losses, the efficiency can be as high as 99.7%. The input and output measurements of a transformer are not done under loaded conditions as the wattmeter readings inevitably suffer errors of 1 – 2%. So for the purpose of efficiency calculations, OC and SC tests are used to calculate rated core and winding losses in the transformer. The core losses depend on the transformer rated voltage, and the copper losses depend on the currents through the transformer primary and secondary windings. Hence transformer efficiency is of prime importance to operate it under constant voltage and frequency conditions. The rise in the temperature of the transformer due to heat generated affects the life of ...

A  Transformer  is a static electrical machine which transfers AC electrical power from one circuit to the other circuit at the constant frequency, but the voltage level can be altered that means voltage can be increased or decreased according to the requirement. It works on the principle of  Faraday’s Law of Electromagnetic Induction  which states that “ the magnitude of voltage is directly proportional to the rate of change of flux.” Contents: Necessity of a Transformer Construction of a Transformer Types of Transformer EMF Equation of the Transformer Losses in the Transformer Efficiency of the Transformer Necessity of a Transformer Usually, electrical power is generated at 11Kv. For economical reasons AC power is transmitted at very high voltages say 220 kV or 440 kV over long distances. Therefore a step-up transformer is applied at the generating stations. Now for safety reasons the voltage is stepped down to different levels by step down transformer at various s...

Single Phase Transformer Full-Load Current (Amps)= kVA × 1000 / V Three Phase Transformer Full-Load Current (Amps) = kVA × 1000 / (1.732 × V) Where: kVA  = transformer rating (kilovolt-amperes), V  = voltage (volts).   Turns Ratio = N 1  / N 2  = V 1  / V 2  = I 2  / I 1 Where: N 1  = number of turns on the primary, N 2  = number of turns on the secondary, V 1  = primary voltage, V 2  = secondary voltage, I 1  = primary current, I 2  = secondary current.   Example:  A 50 kVA single-phase transformer has a 4000 V primary, and a 400 V secondary. Assuming an ideal transformer, determine (a) the primary and secondary full-load currents, (b) the transformer turns ratio. a)  V 1  = 4000 V, V 2  = 400 V, Transformer Rating = 50 kVA = V 1  × I 1  = V 2  × I 2 Primary full-load current, I 1  = (50 × 1000 / 4000) = 12.5 A Secondary full-load current, I 2  = (50 × 1000 / 400) = 1...