122 PROBLEMS IN ALTERNATING CURRENT MACHINERY 



48.6 ohms and 59.4 ohms per conductor respectively. The gen- 

 erator has an effective armature resistance of 0.36 ohm per phase. 

 The open- and short-circuit characteristic data for the generator 

 are: 



With the far end of the transmission line short-circuited the 

 generator supplies a current of 165 amperes at a terminal potential 

 of 860 volts, and the power delivered to the transformers and line 

 is 146 kw. 



If, when the far end of this transmission line delivers a balanced 

 load of 1450 kw. at a power factor of 0.93, the line potential differ- 

 ence at the load is 30,000 volts, to what value would this voltage 

 rise if the load were removed? Use what you consider the most 

 exact method of calculation. 



70. A 1000-kv.-a., 13,800-volt generator delivers power over 

 a transmission line and through step-down transformers which are 

 connected in delta on both the high- and low-tension sides. The 

 armature windings of the generator, which are connected in Y, 

 have an effective resistance of 2.18 ohms per phase. The resist- 

 ance of the field circuit is 0.541 ohm. 



GENERATOR CHARACTERISTICS 



The friction and windage loss is 7.9 kw. 



TRANSFORMER CHARACTERISTICS 



Each transformer has a ratio of transformation of 425:13,200 

 volts. With the low-tension winding short-circuited and with 

 1100 volts impressed on the high-tension winding the current 



