A salient pole synchronous motor is connected to an infinite bus over a short feeder whose impedance is purely reactive. The power-angle curve for transient condition is P'(δ') = 1.3 sin δ' + 0.2 sin 2δ' where the amplitudes are in pu on the machine rated base values. With the motor operating initially unloaded, a shaft load of 0.70 pu is suddenly applied.
a) Compute the operating torque angle δss
b) Assume δss = 25 degrees and computer areas A1 and A2.
c) Compute the maximum torque angle δmax that the motor can operate and remain in synchronism with the infinite bus.
Attachment:- Electrical Power system.doc