402 ELECTRICAL ENGINEERING 



The power factor at the generator is 

 #cos<+7r 53,000 



000 = 0.828 = 82.8 per cent. 



Using rectangular coordinates and taking the current as axis, 

 the e.m.f. at the receiver terminals is 



E = E cos <J> + jE sin <, 

 the e.m.f. consumed in the impedance of the line is 



and the generator e.m.f. is 



EG = E + E' = (E cos < + Ir) + j (E sin + 7x), 

 and its absolute value is 



EG = (E cos <j> + 7r) 2 + (# sin + /a:) 2 . 



The capacity of the line has been neglected in this example. 



(2) A transmission line of impedance z = r + jx delivers 

 power to a receiver circuit of admittance y = g jb at a con- 

 stant voltage E. If the capacity of the line is assumed to be 

 concentrated at the centre determine the charging current of the 

 line, the total current delivered by the generator and the terminal 

 voltage of the generator. 



The condensive reactance of the line is 



where / is the frequency of the impressed e.m.f. and C is the ca- 

 pacity of the line in farads; the condensive susceptance of the 

 line is 



fc = & = - 



AC 



and it is represented as a condenser connected across the line. 

 (Fig. 376.) 

 The current in the receiver circuit is 



I =E(g-jb), 

 and the e.m.f. at the centre of the line is 



