Understanding Motor Controls
4th Edition
ISBN: 9781337798686
Author: Stephen L. Herman
Publisher: Delmar Cengage Learning
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Chapter 36, Problem 5RQ
Why are SCRs used to construct a bridge rectifier in many solid-state variable frequency drives?
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A particle is held and then let go at the edge of a circular shaped hill of radius R =
shown below. The angular motion of the particle is governed by the following ODE:
+ 0.4 02 - 2 cos 0 + 0.8 sin 0 = 0
where is the angle in rad measured from the top (CCW: +), ė
5m, as
= wis the velocity in rad/s,
==a is the angular acceleration in rad/s². Use MATLAB to numerically integrate the
second order ODE and predict the motion of the particle.
(a) Plot and w vs. time
(b) How long does it take for the particle to fall off the ring at the bottom?
(c) What is the particle speed at the bottom. Hint v = Rw.
in de
all questions
the particles inside the tube.
/2/07/25
Particle
R
0
0
R
eled with
If FA = 40 KN and FB = 35 kN, determine the magnitude of
the resultant force and specify the location of its point of
application (x, y) on the slab.
30 kN
0.75 m
90 kN
FB 2.5 m
20 kN
2.5 m
0.75 m
FA
0.75 m
3 m
3 m
0.75 m
The elastic bar from Problem 1 spins with angular velocity ω about an axis, as shown in the figure below. The radial acceleration at a generic point x along the bar is a(x) = ω 2 x. Under this radial acceleration, the bar stretches along x with displacement function u(x). The displacement u(x) is governed by the following equations: ( d dx (σ(x)) + ρa(x) = 0 PDE σ(x) = E du dx Hooke’s law (2) where σ(x) is the axial stress in the rod, ρ is the mass density, and E is the (constant) Young’s modulus. The bar is pinned on the rotation axis at x = 0 and it is also pinned at x = L.
Determine:1. Appropriate BCs for this physical problem.2. The displacement function u(x).3. The stress function σ(x).
Chapter 36 Solutions
Understanding Motor Controls
Ch. 36 - Prob. 1RQCh. 36 - Prob. 2RQCh. 36 - If an alternator is used to provide variable...Ch. 36 - What solid-state device is generally used to...Ch. 36 - Why are SCRs used to construct a bridge rectifier...Ch. 36 - What is the main disadvantage of using SCRs in a...Ch. 36 - How are junction transistors driven into...Ch. 36 - What is the disadvantage of driving a junction...Ch. 36 - Prob. 9RQCh. 36 - In variable frequency drives that employ IGBTs,...
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