A load of 1000 kW at 0·8 p.f. lagging is received at the end of a 3-phase line 20 km long. The resistance and reactance of each conductor are 0·25 Ω and 0·28 Ω per km. If the receiving end line voltage is maintained at 11 kV, calculate : (i) sending end voltage (line-to-line) (ii) percentage regulation(iii) transmission efficiency [(i) 11·84 kV (ii) 7·61% (iii) 94·32%]

Question

A load of 1000 kW at 0·8 p.f. lagging is received at the end of a 3-phase line 20 km long. The resistance and reactance of each conductor are 0·25 Ω and 0·28 Ω per km. If the receiving end line voltage is maintained at 11 kV, calculate :

(i) sending end voltage (line-to-line) (ii) percentage regulation
(iii) transmission efficiency [(i) 11·84 kV (ii) 7·61% (iii) 94·32%]