5.21 only Short-circuit test: I_f = 925 A, I_a = 7320 A a. Find AFNL, AFNL_ag an

Question

5.21 only

Short-circuit test: I_f = 925 A, I_a = 7320 A a. Find AFNL, AFNL_ag and AFSC. b. Find (i) the short-circuit ratio, (ii) the unsaturated value of the synchronous reactance in ohms per phase and per unit and (iii) the saturated synchronous reactance in per unit and in ohms per phase. Using MATLAB, plot the field current required to achieve unity-power-factor operation for a motor operating at rated terminal voltage as the motor load varies from zero to full load. Exercise your program on the motor of Problem 5.15. The motor of Problem 5.15 has a phase resistance of 42 m Ohm and a field-winding resistance at 25 degree C = 0.218 Ohm both at 25 degree C. Loss data for the motor of Problem 5.15 are as follows: Open-circuit core loss at 4160 V = 47 kW Friction and windage loss = 23 kW a. Compute the input power and efficiency when the motor is operating at rated output power, unity power factor, and rated terminal voltage. Assume the field-winding to be operating at a temperature of 125 degree C and the stator winding to be operating at 140 degree C. b. Repeat the calculation of part (a) assuming the motor to be operating at a load of 3.5 MW and a leading power factor of 0.8. A 125-MVA, 11-kV, three-phase, 50-Hz synchronous generator has a synchronous reactance of 1.33 per unit. The generator achieves rated open-circuit voltage at a field current of 325 A. The generator is operating on a system with an equivalent line-line voltage of 11 kV and an equivalent impedance of 0.17 per unit on the generator base. The generator is loaded to a real power of 110 MW. (i) Calculate the generated voltage E_af in per unit and in kV (line-line) such that the system is operating at unity power factor at the external-system equivalent voltage. Calculate (ii) the corresponding field

Explanation / Answer

Dear Sir,

5.21 question has completely missed. If you don't mind can you please upload it again.

Thanks and Ragards,

Gowri sankar

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.