CHAPTER XIII 



EFFECT OF CHARGING CURRENT 



THE electrostatic capacity of a transmission line, 

 which causes the well-known charging current observed 

 at no load, has often been stated to be a considerable dis- 

 advantage. However, the reverse is probably the case. 

 A casual inspection of Tables I and III will not show at 

 once the true effect of line capacity; neither can its 

 effect be judged by observation of the line when power 

 is being transmitted. Since the charging current is 

 only observable at no load, when it often necessitates 

 the running of a comparatively large quantity of gener- 

 ators and when it also produces a rise in the receiver 

 voltage, it is sometimes forgotten, or not considered, 

 that the charging current is as helpful in reducing the 

 generator load and raising the power factor at full load 

 as it is troublesome in increasing the work of the gen- 

 erators at no load. Thus the charging current may be 

 said to improve the load factor, since it is helpful at times 

 of heavy load, and the reverse at times of light load. 

 Although the charging current often has a considerable 

 effect on the line voltage, this effect is present at both 

 no load and full load, and so the result on the regulation, 

 that is, the voltage variation, is very slight. What 

 effect does exist results in making the line regulation 

 better. A careful comparison of the formulas, including 



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