申論題

5. (15%) A 60-Hz synchronous generator having inertia constant H= 5 MI/MVA and a direct axis transient reactance X'_d = 0.36 per unit is connected to infinite bus through a purely reactive circuit as shown in Fig. 3. Reactance are marked on the diagram on a common system base. The generator is delivering real power P_e = 0.8 per unit to the infinite bus at a voltage of V = 1 per unit. Voltage magnitude at bus 1 is 1.2 per unit. A temporary three- phase fault occurs at the sending end of the line at point F through a fault impedance of Z_f = j0.2 per unit. When the fault is cleared, both lines are intact.