exam2_solution

# exam2_solution - ECE 321 Problem 1 Exam 2 Solution Spring...

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ECE 321 Exam 2 SolutionSpring 2006 Problem 1 SL 15 π 180 := N 3 := TP SL N := RT 2 π TP := RT 8 = L ls L A + L B + 5mH = L ls L A + L B 1mH = L ls L A + 3mH = L B 2mH = L asas L ls L A + L B cos RT θ rm () + = 0.003 0.002cos 8 θ rm + = H Problem 2 Equilibrium points on the positive slope of the Te curve are unstable. For example, assume the load torque is constant and the rotor is at rest at an equilibrium point on the positive slope of the Te curve. θ 0 π 50 , 2 π .. := 0 100 200 300 1 0 1 cos θ .5 θ 180 π unstable equilibrium point -> Since J t ω rm d d T e T L = if the rotor is perturbed a small amount in the negative θ rm direction, then Te < TL, and the rotor will continue to accelerate in the negative θ rm direction, thus moving away from the equilibrium point. Similarly, if the rotor is instead perturbed in the positive θ rm direction, Te < TL, and the rotor accelerates in the positive θ rm direction, again moving away from the equilibrium point. Hence this equilibrium point is unstable.

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Problem 3 A single phase of each is shown.
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## This note was uploaded on 02/19/2012 for the course ECE 321 taught by Professor Staff during the Spring '08 term at Purdue.

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exam2_solution - ECE 321 Problem 1 Exam 2 Solution Spring...

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