An engineer considers increasing the rms transmission voltage on an existing line by…
PHYSICS · Subjective · CBSE · Physics · Alternating Current · Alternating Current
Problem
An engineer considers increasing the rms transmission voltage on an existing line by a factor k while keeping the power to be delivered and the line resistance unchanged.
(i) Derive an expression, in terms of k, for the ratio of the new line loss to the original line loss.
(ii) Hence obtain a formula for the percentage saving in line loss achieved by this change.
(iii) For a line that originally carried 4MW at 20kV through conductors of total resistance 6Ω, calculate the percentage saving when the transmission voltage is raised so that k=6.