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Anyone there to help me ASAP?A 3-phase induction machine is connected to an infinite bus through a double circuit line

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Anyone there to help me ASAP?A 3-phase induction machine is connected to an infinite bus through a double circuit line. Suppose a three phase fault takes place at the mid point of one feeder. Three circuit breakers are connected across all the three terminals. Cascaded sets of alternators are connected through the feeder. The reactance of the alternator and the tie line are 1.1 p.u and 0.4 p.u.

Determine the center and radius for the pull out curve. Determine the inertia constant of the equivalent machine. Plot the swing curve both for the sustained fault condition and when fault is cleared. Determine the allowable sudden load that can be switched on without loss of stability.

A 3-phase induction machine is connected to an unbalanced star-delta connected transformer.

The reactance and impedance of the transformer are 1.2 p.u and 0.7 p.u.

The armature current upon symmetrical 3- phase short-circuit of a synchronous machine parallerly attached with a 50 Hz alternator is rated 500MVA, 440Kv. It supplies a purely resistive load of 400 Mw at 20 KV. The load is connected directly across the transformer terminals. The direct axis and quadrature axis reactance of a salient pole alternator are 1.2 p.u and 1.0 p.u

1.Find the angle between the stator voltage and current.

2.Draw the phasor diagram of whole network.

3.Find the short circuit characteristics of the whole system.

4.How can the reactive power delivered by the synchronous generator be controlled.

5.Draw the magnetization curve for the rated armature current.

 

A 440 V, 3-phase, delta connected cylindrical synchronous motor with synchronous reactance of ?Xsm?=2Ω? is connected to a turbo-generator with ?Xsg?=3Ω? through transmission line of reactance ?Xtr?=1.5Ω?. If its field current is adjusted to give an

excitation voltage of 12 Kv, then Calculate:

(a) Calculate the maximum magnitude of the resultant flux emf?

(b) Calculate the magnitude of armature current and its P.F?

(c) Calculate the magnitude of the armature current in phase with stator voltage?

(d) Calculate the maximum power output from the motor?

(e) Compute the excitation voltage ?Ef?? on a per unit basis, when the generator is delivering rated KVA at rated voltagee and at power factor of (i) 0.8 lagging and (ii)0.8 leading?

(f) Draw the complete phasor diagram and show that armature current leading the terminal voltage?