Answer Posted / guest

C.R.G.O (Cold-rolled grain-oriented sheet steel) is used for reducing the core losses in transformers.
Each type of steel has "grains" which consist of "domains". These "domains" are nothing but electrical charges oriented in any random direction.

Core loss= Hysteresis + Eddy Current Loss

Reduction of hysteresis loss:
(1)The size of the "grains" in a CRGO steel are purposely "grown" & made bigger & are about 10 times the size of the grains in regular steel.
(2)The grains in CRGO steels are all aligned almost parallel to the direction of rolling of the steel(i.e the length of the steel).

Reduction of eddy current loss:
A special carlite insulation coating on the steel being done so as to reduce the eddy current loss.

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