15-05-2014, 10:22 AM
TRANSFORMERS
TRANSFORMERS .pptx (Size: 898.48 KB / Downloads: 317)
A transformer is a static machines.
The word ‘transformer’ comes form the word ‘transform’.
Transformer is not an energy conversion device, but is a device that changes AC electrical power at one voltage level into AC electrical power at another voltage level through the action of magnetic field, without a change in frequency.
It can be either to step-up or step down.
Ideal Transformer
An ideal transformer is a transformer which has no loses, i.e. it’s winding has no ohmic resistance, no magnetic leakage, and therefore no I2 R and core loses.
However, it is impossible to realize such a transformer in practice.
Yet, the approximate characteristic of ideal transformer will be used in characterized the practical transformer.
Voltage Regulation
The purpose of voltage regulation is basically to determine the percentage of voltage drop between no load and full load.
Voltage Regulation can be determine based on 3 methods:
a) Basic Defination
b) Short – circuit Test
c) Equivalent Circuit
Tap Changer
A transformer tap is a connection point along a transformer winding that allows a certain number of turns to be selected.
By this means, a transformer with a variable turns ratio is produced, enabling voltage regulation of the output. The tap selection is made via a tap changer mechanism.
TRANSFORMERS .pptx (Size: 898.48 KB / Downloads: 317)
A transformer is a static machines.
The word ‘transformer’ comes form the word ‘transform’.
Transformer is not an energy conversion device, but is a device that changes AC electrical power at one voltage level into AC electrical power at another voltage level through the action of magnetic field, without a change in frequency.
It can be either to step-up or step down.
Ideal Transformer
An ideal transformer is a transformer which has no loses, i.e. it’s winding has no ohmic resistance, no magnetic leakage, and therefore no I2 R and core loses.
However, it is impossible to realize such a transformer in practice.
Yet, the approximate characteristic of ideal transformer will be used in characterized the practical transformer.
Voltage Regulation
The purpose of voltage regulation is basically to determine the percentage of voltage drop between no load and full load.
Voltage Regulation can be determine based on 3 methods:
a) Basic Defination
b) Short – circuit Test
c) Equivalent Circuit
Tap Changer
A transformer tap is a connection point along a transformer winding that allows a certain number of turns to be selected.
By this means, a transformer with a variable turns ratio is produced, enabling voltage regulation of the output. The tap selection is made via a tap changer mechanism.