申論題

六、(16%)計算題A60-Hz three-phasesynchronous getor ott H= MMVA and a direct axis transient reactance X_d =0.3 p.u. is connected to an infinite bus through a purely reactive circuit as shown in Fig. 3. Reactances are marked on the diagram in a common system base. The generator is delivering real power Pe= 0.8 p.u. and Q=0.074 p.u. to the infinite bus at a voltage of V=1 p.u.

(ㅡ)、A temporary three-phase fault occurs at the sending end of the line at point F. When the fault is cleared, both lines are intact. Determine the critical clearing angle δ ₁. (7%)