Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 33, Problem 7SQ
Why are different motor connections shown for what appears to be the same motor in the various diagrams in Figure 33–2?
FIG. 33–2 Typical arrangements for four-speed, three-phase, two-winding motors.
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13. The main and auxiliary windings of a hypothetical 110-V, 60-Hz, split-phase motor have the following locked-rotor parameters: Rmw = 2.2 Ohms, Xmw = 3.2 Ohms, Raw = 9.63 Ohms, and Xaw = 8.9 Ohms. The motor is connected to a 110-V, 60-Hz system. Determine the external resistance in Ohms required in series with the auxiliary winding in order to obtain a 26 degrees phase displacement between the currents in the two windings.
Correct Answer:
6.11
Q choose the correct answer:
1-Brushless excitation system consisting of....
a- Stator field winding and power diodes
b-stator and rotor field winding and capacitor
c- stator and rotor field winding and capacitor
d- Everything mentioned in the options
2- Voltage generated per phase in an alternator is
proportional to
a- Flux per pole
b- Number of turns in armature
c-Winding factors
d- Everything mentioned in the options
e- Frequency of waveform
3- If input mech. Power of SG constant, the functionality of
AVR is
a- Control flux of rotor
b-Control terminal voltage
c- Control flux and terminal voltage
d-Control Load angle
Q.21
How are the start and run windings of a split-phase motor connected in relation to each other?
Select one:
A. PARALLEL
B. SERIES
C. INDEPENDENT
Chapter 33 Solutions
Electric Motor Control
Ch. 33 - Prob. 1SQCh. 33 - Prob. 2SQCh. 33 - Prob. 3SQCh. 33 - What is the primary reason for using a compelling...Ch. 33 - What is the purpose of an accelerating relay?Ch. 33 - When is it most important to use decelerating...Ch. 33 - Why are different motor connections shown for what...Ch. 33 - How many windings are required for three-speed...
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