Homework_3_2011

# Homework_3_2011 - a Given that only one winding is used at a time what sequence of currents(polarity and phase should be imposed for

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ECE 431 homework assignment #3 Due in class – Friday, February 11, 2011 1. Textbook problem 3.7. Use g =0.5 mm, A 0 =5mm 2 , and N =500 turns. The permeability of the moving vane is infinite, but the core has a permeability μ c = μ r μ o where μ r =1000. In part (b), you can use either MATLAB or MS Excel to generate your plot. 2. A variable reluctance machine has an 8/6 configuration, as shown in Fig. 3. There are four winding sets, not shown, in counter-clockwise sequence on the stator poles as a, b, c, d, a’, b’, c’, d’. Each winding can have either positive or negative current imposed on it. The position shown is the reference position at zero degrees.
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Unformatted text preview: a) Given that only one winding is used at a time, what sequence of currents (polarity and phase) should be imposed for counter-clockwise rotation? b) If the currents are switched sequentially each 1 ms, how fast will the motor rotate, assuming the inductance is small (i.e. the time constant is small and the machine response is instantaneous)? c) It is proposed instead that two windings be used at a time. What sequence should be used for counter-clockwise rotation in this case? 3. Bonus: Textbook problem 3.22. The air gap lengths are not equal as stated in the textbook. Assume they are g o and g 1 (+2 points)....
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## This note was uploaded on 08/25/2011 for the course ECE 431 taught by Professor Bazzi during the Spring '11 term at University of Illinois at Urbana–Champaign.

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