A 2-pole, 3-phase Doubly Fed Induction Generator (DFIG) is rated at VLLrms 480 V at 50...

 

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A 2-pole, 3-phase Doubly Fed Induction Generator (DFIG) is rated at VLLrms 480 V at 50 Hz. Its parameters are as follows: R, = 0.0082, L₁s = 0.1 mH, Lm = 3.7 mH. R 0.01722, and Ltr = 0.2 mH. Assume the friction, windage, and iron losses to be negligible. The rotor to stator winding ratio is 3.0 to 1.0. The stator of the generator is supplying active power of 120 kW and a reactive power of 48 kVAR capacitive to the grid at a rotational speed of 3,300 rpm. a) [2 Marks] Draw the d and q axis equivalent circuits (including the parasitic elements) assuming the d-axis is aligned with the rotor flux. b) [3 Marks] Calculate the d-axis and q-axis voltages applied by the power-electronics con- verter to the rotor circuit, and the resulting d-axis and q-axis rotor currents. For this part of the question you can assume all parasitic inductances and resistances are zero. A 2-pole, 3-phase Doubly Fed Induction Generator (DFIG) is rated at VLLrms 480 V at 50 Hz. Its parameters are as follows: R, = 0.0082, L₁s = 0.1 mH, Lm = 3.7 mH. R 0.01722, and Ltr = 0.2 mH. Assume the friction, windage, and iron losses to be negligible. The rotor to stator winding ratio is 3.0 to 1.0. The stator of the generator is supplying active power of 120 kW and a reactive power of 48 kVAR capacitive to the grid at a rotational speed of 3,300 rpm. a) [2 Marks] Draw the d and q axis equivalent circuits (including the parasitic elements) assuming the d-axis is aligned with the rotor flux. b) [3 Marks] Calculate the d-axis and q-axis voltages applied by the power-electronics con- verter to the rotor circuit, and the resulting d-axis and q-axis rotor currents. For this part of the question you can assume all parasitic inductances and resistances are zero.