Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
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Textbook Question
Chapter 21, Problem 6RQ
What is the full-load running current of a three-phase, 50-hp motor connected to a 560-volt line? What are the minimum size NEMA and IEC starters that should be used to connect this motor to the line?
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Q7 (12 Marks)
For the system shown in Fig.3:
1- Draw the overall block diagram.
2- Determine the transfer function (Pc(s)/E(s)).
Orifice→
Ps
Actuating error signs)
Flapper
Pb+Pb.
Nozzle.
A
X+X+
Ri
A
I
R2
ㅍ
think
+y
Pc+PC
Figures 4: show a pneumatic controller. The pneumatic
relay has the characteristic
that pc=K pb
, where K>0. What kind of control action does this
controller produce?
a. Derive the mathematical model for the system
b. Derive the transfer function Pc(s)/E(s)
-Solve step by step
Orifice
F+Ph
R₁
Actuating error signal
Flapper
Nozzle.
x+x
F+Pe
think
The equation of the turning moment diagram for the three crank engine and the equation
of the moment required by a machine connected to this engine are given below:
Engine Torque
Machine Torque
T=10000-500 sin (40)
T=10000+2000 sin (20)
N.m
N.m
where
radians is the crank angle from inner dead center and the mean engine speed is
300 rpm. It is required to select a proper flywheel (find the moment of inertia of the flywheel
in kgm2) and then calculate the power of the engine if the total percentage fluctuation of
speed of the flywheel is ±1% of the mean speed. Calculate the angular acceleration of the
flywheel when angle is 45°.
Chapter 21 Solutions
Electrical Transformers and Rotating Machines
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