1.
2.
ECE 3300 ELECTRIC MACHINERY FALL 2015 HOMEWORK #3 DUE: 10/05/2015
A ring, shown in Fig. P2.1, has a mean diameter of 21 cm and a cross-sectional area of Ax = 10 cm2. The
ring is made up of semicircular sections of cast iron and cast steel, with each
ECE 3300 ELECTRICAL MACHINERY FALL 2015 HOMEWORK #1
DUE: 09/21/2015
1.
Consider the network of Fig. P1.1.
(a)
Determine currents I1, I2, I3, I4, and I5.
(b)
Determine the total real power consumed.
(c)
Determine the total reactive power consumed.
(d)
Dete
ECE 3300 ELECTRIC MACHINERY FALL 2015 HOMEWORK #7
DUE: 11/16/2015
1.
A 4-pole, 240-V DC, wave connected shunt motor gives 11.19 kW when running at 1000 rpm and
drawing armature and field currents of 50 A and 1.0 A, respectively. It has 540 conductors. The
ECE 3300 ELECTRICAL MACHINERY FALL 2015 HOMEWORK #2 DUE: 09/28/2015
1. The balanced, 3-phase, wye-connected load is supplied by a balanced wye-connected source over a
balanced 3-phase line as shown in Fig. P1.1. The voltage at sending end is 66 kV and the
SJ. Katzen University of Ulster, School of Electrical and Mechanical Engineering
S.J. Katzen
University of Ulster, School of Electrical and Mechanical Engineering
SJ. Katzen
University of Ulster, School of Electrical and Mechanical Engineering
SJ. Katzen
SJ. Katzen
University of Ulster, School of Electrical and Mechanical Engineering
SJ. Katzen
University of Ulster, School of Electrical and Mechanical Engineering
*
v
vdt
d
dt
N
*N
A
*A
B
*
H
*l
l
N
*N
I
L
*L
R
*R
v = voltage (V);
= flux linkage (HA: Henry Ampere)
= flux (Wb: Weber)
I = current (A: Ampere)
B = flux density (Wb/m2 or Tesla)
= reluctance (At/Wb: ampere turns per weber) = l/(A)
H = magnetic intens
ECE 3300 ELECTRIC MACHINERY FALL 2015 HOMEWORK #4
DUE: 10/12/2015
1.
A 5000-kVA, 3-phase transformer, 6.6/33-kV, /Y, has no-load loss of 15 kW and a full-load loss of 50
kW. The impedance referred to the secondary is Zeq2 = 1.53 + j15.23 /phase. The trans
ECE 3300 ELECTRIC MACHINERY FALL 2015 HOMEWORK #6
DUE: 11/09/2015
1.
A coil of an electromagnetic relay is associated with a magnetic circuit
whose reluctance is given by
= a + bx
where a and b are positive constants decided by the details of the magneti
ECE 3300 ELECTRIC MACHINERY FALL 2015 HOMEWORK #8
DUE: 12/07/2015
1.
A 3-phase induction motor having a 6-pole, star-connected stator winding runs on
240-V, 50 Hz supply. The rotor resistance and standstill reactance are 0.12 and
0.85 . The ratio of stato
ECE 3800 Probabilistic Methods of
Signal and System Analysis, Spring 2016
Course Topics:
1. Probability
a. Bayes Theorem
b. Combinatorials
2. Random variables
a. probability density function (pdf)
b. probability mass function (pmf)
c. cumulative distribut
ECE 3800 Probabilistic Methods of
Signal and System Analysis, Spring 2015
Course Topics:
1.
2.
3.
4.
5.
6.
7.
8.
Probability
Random variables
Multiple random variables
Elements of Statistics
Random processes
Correlation Functions
Spectral Density
Reponses
ELECTROMECHANICAL ENERGY CONVERSION
Chp. 3
Fig. 3.1
electrical mechanical increase
field
energy energy
energy
output
input
stored losses
losses losses
Electrical losses = resistance
Mechanical losses = friction and windage
Field losses = l
DC MACHINES
CHARACTERISTICS, TORQUE, AND SPEED CONTROL
SERIES MOTORS:
Characteristics: (see FIGURE 4.55)
Ka = KsrIa
(4.49)
From equations (4.9), (4.17) and (4.49)
Ea = KsrIam
(4.50)
T = K a I a = K sr I a2
(4.51)
Vt = Ea + Ia(Ra + Rae + Rsr)
Ea = Vt Ia(Ra
ECE 3800: EXAM #3
Given a random process, X t A B sin 2 f 0 t , where A is uniformly
1. [40 pts])
distributed random variable on 1,7 , B is a constant and is a uniformly distributed random
variable on 0,2 . In addition, A and are independent.
a.(10) Deriv
ECE 3800: EXAM #3
1. [40 pts])
Given a random process, X t A B sin 2 f 0 t , where A is uniformly
distributed random variable on 1,7 , B is a constant and is a uniformly distributed random
variable on 0,2 . In addition, A and are independent.
a.(10) Deriv
1
ECE 3300 ELECTRICAL MACHINERY TEST II TIPS
There will be 3 questions and you are to answer all. BLUE BOOKS
REQUIRED. Areas to be covered:
1.
Electromechanical Energy Conversion
(a) Energy Conversion Process
(b) Linear mechanical Energy at Constant Curre
Force
'. .
(a)
Force Due to Magnetic Fields
(a) Permanent Magnets
(b) Electri Coils
(b)
I
I
(a)
(b)
Parallel Current-Carrying Conductors
(a) Overall View
(b) End View
.
-~- _
_L_ _
B
Ilustration of the Left-Hand (Motor) Rule
(a)
(b)
(c)
(d)
OpeFation of
CYLINDRICAL MACHINES
Lsr = M cos
(3.46)
where
M = is peak value of mutual inductance Lsr.
= is angle between magnetic axis of the stator and rotor windings
The currents in the stator and rotor windings are respectively
is = Ismcos st
(3.47)
is = Irmcos
POWER FLOW OF THE DC MOTOR
Input Power (Pin) Pin = VtIt
Ideal Motor
(No Losses )
Airgap Power (Pag)
Field Losses
Pag = VaIt
Field Losses (Pcu 1)
Stator Core
Losses (Piron 1) P 3I 2 R
cu1
f
f
Armature Losses
Rotor Core
Losses (Piron 2)
Electromagnetic Powe
Experiment 1
Balanced and Unbalanced Three-Phase Circuits
1.1 Introduction
The purpose of this experiment is to study current, voltage, and power distribution in balanced and
unbalanced, wye, and delta connected three-phase loads. With this experiment, th
Experiment 1 Balanced and Unbalanced Three-Phase Circuits
1.1 Introduction
The purpose of this experiment is to study current, voltage, and power distribution in balanced and
unbalanced, wye, and delta connected three-phase loads. With this experiment, th