2)
A three-phase synchronous generator is rated 16 kV and 200 MVA,has negligible losses and has reactance of 1.65 pu. The generatoris operated on an infinite bus of 15 kV voltage and delivers 100MVA at 0.8 Power Factor, lagging.
a)Determine the internal voltage (E_i), the power angle (δ), andthe line current of the machine.
b)If the field current of the machine is reduced by 10%, whilethe mechanical power input to the machine is maintained constant,determine the new value of the power angle (δ) and reactive powerdelivered to the system.
c)The prime mover is next adjusted without changing theexcitation so that the machine delivers zero reactive power to thesystem. Determine the new power angle (δ) and the real power beingdelivered to the system.
d)What is the maximum reactive power that the machine candeliver if the level of excitation is maintained as in part b?