Page 59 - Solutions Manual to accompany Electric Machinery Fundamentals

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2-14. A 13.8-kV single-phase generator supplies power to a load through a transmission line. The load’s
impedance is Z load   500 .  3687  , and the transmission line’s impedance is Z line  60 60   .

(a) If the generator is directly connected to the load (Figure P2-3a), what is the ratio of the load voltage
to the generated voltage? What are the transmission losses of the system?
(b) What percentage of the power supplied by the source reached the load (what is the efficiency of the
transmission system)?
(c) If a 1:10 step-up transformer is placed at the output of the generator and a 10:1 transformer is placed
at the load end of the transmission line, what is the new ratio of the load voltage to the generated
voltage? What are the transmission losses of the system now? (Note: The transformers may be
assumed to be ideal.)
(d) What percentage of the power supplied by the source reached the load now?

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