In: Electrical Engineering
Ans)
Given line voltages
phase voltages are
Given load current is
phasor diagram for this load is
from the phasor diagram above using inner triangle
is the reactance of the generator
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Now for full load 0.8 pf lagging
full load current is
regulation at this current is
this answer is calculated using matlab hence it is accurate ,if you use hand calculator neglecting some decimals you will get 13.5 % as given in answer
Phasor diagram at this load is