A three-phase synchronous generator is rated 16 kV and 200 MVA, has negligible losses and has...

A three-phase synchronous generator is rated 16 kV and 200 MVA, has negligible losses and has reactance of 1.65 pu. The generator is operated on an infinite bus of 15 kV voltage and delivers 100 MVA at 0.8 Power Factor, lagging.

a)Determine the internal voltage (E_i), the power angle (δ), and the line current of the machine.

b)If the field current of the machine is reduced by 10%, while the mechanical power input to the machine is maintained constant, determine the new value of the power angle (δ) and reactive power delivered to the system.

c)The prime mover is next adjusted without changing the excitation so that the machine delivers zero reactive power to the system. Determine the new power angle (δ) and the real power being delivered to the system.

d)What is the maximum reactive power that the machine can deliver if the level of excitation is maintained as in part b?

Expert Solution

Manojponduru answered 8 months ago

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