Four times
Eddy current losses in a transformer are proportional to the square of the supply frequency and the square of the magnetic flux density. The formula for eddy current loss is given by:
\(P_e = K f^2 B^2 t^2\)
where:
If the supply frequency (\(f\)) is doubled, while other factors remain constant, the eddy current loss will change as follows:
Original loss: \(P_{e1} = K (f)^2 B^2 t^2\)
New loss with doubled frequency: \(P_{e2} = K (2f)^2 B^2 t^2 = 4 K (f)^2 B^2 t^2 = 4 P_{e1}\)
Therefore, the eddy current loss will become four times its original value.
The lamination thickness of a rotor should be selected from _______ to minimize the eddy current loss.
Eddy current loss in a transformer can be reduced by _________.
Stray load-losses in a motor vary according to square of the load current; are caused by the leakage flux induced by load currents in laminations and account for 4% to 5% of total losses. What is the way to reduce these losses?
The core loss of a single phase, 230/115 V, 50Hz power transformer is measured from 230 V side by feeding the primary (230 V side) from a variable voltage variable frequency source while keeping the secondary open circuited. The core loss is measured to be 1050 W for 230 V, 50 Hz input. The core loss is gain measured to be 500 W for 138 V, 30 Hz input. The hysteresis and eddy current losses of the transformer for 230 V, 50 Hz input are respectively