PROPERTY OF ELECTRICAL LABORATORY, 



FACULTY OF APPLIED SCIENCE. 



Date., 



CHAPTER VIII. 

 TRANSMISSION LINE PROBLEMS. 



WHEN conditions are given at the receiver, or load, end of 

 a transmission line, the convergent series of Table V give 

 at once the voltage, A + JB, and the current, C +JD, at 

 the other end of the line. By putting the load current 

 equal to zero, we obtain the following expression for the 

 no-load voltage at the supply end: 



V7 V 2 7 2 



C 



Thus the ratio of the voltages at the two ends of the line at 

 no load is 



+ _ 



E \ 2 2-3.4 / 



which is independent of the voltage E, and depends only 

 on the constants of the line. 



The absolute value of a complex quantity like the volt- 

 age AQ +jBo, is its total numerical value independent of its 

 phase relation. This is the same, in the case of the voltage 

 AQ -\-jBo, as its measured value, and is equal to 



+ o 2 , or ^0 + 7-' 



2A 



to a very close approximation when BQ is smaller than AQ. 

 Since the two complex quantities making up equation (i) 

 are equal in all respects, their absolute values are eaual, 

 and hence 



= absol. value of (i + + -^- + etc.) (2) 

 \ 2 2-3.4 / 



2-3-4 

 57 



