Power transformer with multi winding design

[rotw]

Hello,

I refer to high voltage power transformers (step down) used to feed machinery equipment (rated 16 MW power) ;
My question relates to the multi-winding arrangement of the transformer;

When the turn ratio is changed (say going from 1:3 turn ratio initial configuration to 1:6 turn ratio) what are the pros and cons in terms of reliability of the transformers as the turn ratio is changed ?

What are the parameters for which the design would become more stringent as I keep on changing the turn ratio, particularly by increasing the number of windings at the secondary, e.g. from turn ratio 1:3 to 1:6, keeping the number increasing ?

Thanks

ps: excuse my ignorance on the subject.

"If you want to acquire a knowledge or skill, read a book and practice the skill".

 

[krisys]

In the practical world, 11,000/433 V (i.e; ratio = 25.4) or 33,000/433 V (i.e; ratio = 76.21) are commonly used ratios. Even though the transformation ratio appears to be high. But 220 kV/3.3 kV (i.e; ratio = 66.67) is not a normal ratio. 220 kV/132 kV (i.e; ratio = 1.667)is a commonly used ration.

The transformation ratio is almost standardised for the power distribution system. Is is the parameter of voltage class, power (MVA or kVA) and the standard practice.

Your question of 1:3 ratio is typical of 33 kV/11 kV (i.e; ratio = 3).

Hope it helps you.