A three-phase 50Hz, 500MVA 15kV generator has an inertiaconstant of 2pu/s.
a) For a given power system the initial load angle is δ0 and thechange in
momentum is M. Following a small disturbance the load angleincreases
to δ1. If the accelerating power associated with disturbance is Padeduce
an equation that expresses δ1 in terms of M, Pa δ0 and time,t.
b) Calculate the
i. Synchronous speed
ii. Change in momentum
c) Initially the mechanical and electrical power delivered equal 1pu and the
load angle is 10â°. Calculate the
i. Maximum electrical power
ii. Accelerating power
d) A fault occurs which reduces the electrical power to zero.Calculate the
i. accelerating power
ii. power load angle after 0.05s
