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Problem 2: (25 points) The parameters of a doubly fed induct…

Problem 2: (25 points) The parameters of a doubly fed induction generator are given below. The stator is connected to a three-phase grid at 600 V RMS (line-line) and 60 Hz.  It is given that the rotor speed (electrical rad/s), .  (a) Draw the per-phase equivalent circuit corresponding to the given operating condition and parameters (b) Using grid voltage as the reference phasor , it is given that the voltage across the magnetizing inductance is .  Calculate the phasors . (c) Calculate the total power injected into the grid.

Problem 4: (a) (13 points) Consider a 2-pole PMSM wind gene…

Problem 4: (a) (13 points) Consider a 2-pole PMSM wind generator system delivering 2 MW with a rotor speed of 3000 RPM. Its parameters are . The d axis is aligned with the rotor position, which is given to be -900 at t = 0. The flux linkage in the d-axis winding due to the rotor magnets, . Assume kE = 1. Draw the per-phase equivalent circuit and calculate the phase ‘a’ current.   (b) (12 points) Briefly explain (a short paragraph or a few bullet points) each of the following. (1) Volt-VAR control and (2) Super-synchronous mode of operation in DFIG

Problem 1: (25 points) (a) Consider a three-phase, two-level…

Problem 1: (25 points) (a) Consider a three-phase, two-level converter with dc link voltage of 1000 V.  The CCA value of the line-line voltage generated by the converter is 480 V RMS at 60 Hz.  The switching frequency is 20 kHz. Using space vector PWM, plot the instantaneous for one switching period around t = 8 ms.  Clearly indicate the CCA value of each quantity also at 8 ms. (b) What is the maximum RMS line-line voltage that can be generated from the given 1000V dc link voltage using space vector PWM?