Thursday, 10 November 2016
Bode Plot on Control System
Link For Samarjeet Ghosh
https://drive.google.com/file/d/0Bw9rjAHg9vGMOWF5UVZFbUNQSGM/view?usp=sharing
Link for Study Material on Bode Plot
https://drive.google.com/file/d/0Bw9rjAHg9vGMb0EtMTIwNm42eUU/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMTTgwdDc5UC1KenM/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMLVhhd0FoZkR4Y0E/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMbEpranpGdXFyYTA/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMTEdqWmpmdjdxd0U/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMOXJIT2Q3TVZGbWc/view?usp=sharing
https://drive.google.com/file/d/0Bw9rjAHg9vGMamRNNFpsUk1CRlU/view?usp=sharing
Handout notes will be uploaded shortly
Thank you
Saturday, 22 October 2016
Numerical Sheet On Unit-IV
Numerical Sheet On Unit-IV
Q:-1
An electromagnet has
a gap of 4 mm and flux density in the gap is 1.3 Wb/m2. Determine the
ampere-turns for the gap.
Q:-2
The total core loss
(hysteresis plus eddy-current) for a specimen of magnetic sheet steel is found
to be 1800 W at 60 Hz. If the flux density is kept constant and the frequency
of the supply increased 50%, the total core loss is found to be 3000 W. Compute
the separate hysteresis and eddy-current losses at both frequencies
Q:-3
A coil of 1000 turns
is wound on a laminated core of steel having a cross section of 5 cm2.
The core has an air gap of 2 mm cut at right angle. What value of current is
required to have an air gap flux density of 0.5 T ? Permeability of steel may
be taken as infinity. Determine the coil inductance.
Q:-4
The core of a
magnetic circuit is of mean length 40 cm and uniform cross-sectional area 4 cm2.
The relative permeability of the core material is 1000. An air gap of 1 mm is
cut in the core, and 1000 turns are wound on the core. Determine the inductance
of the coil if fringing is negligible
Q:-5
A coil of 200 turns
is wound uniformly on an iron ring of mean circumference 10 cm and a cross
sectional area 5 cm2. Current 10 Amp is flowing through coil. Relative
permeability of the material is 3000. Find : (i) MMF (ii) Magnetizing force
(iii)Total flux (iv) Reluctance
Q:-6
A circular ring of
mean length 4π cm and of cross-sectional area 10 cm2 has an air gap 0.4 π mm
long. The relative permeability of iron is 1000. The ring is wound with a coil
of 2000 turns. Determine the flux in the air gap, if the coil carries a current
of 2 mA. Also find the inductance of the coil.
Q:-6
A ring of
ferromagnetic material has a rectangular cross section. The inner diameter is
7.4 inches, the outer diameter is 9 inches and the thickness is 0.8 inches.
There is a coil of 600 turns wound on the ring. When the coil carries a current
of 2.5 A, the flux produced in the ring is 1.2 × 10– 3 Wb. Find :
(i) Magnetic field intensity (ii) Reluctance (iii) Permeability
Q:-7 Explain
relative permeability. Calculate the MMF required to produce a flux of 0.015 Wb
across an air gap 2.5 mm long having an effective area of 200 cm2.
Q:-8 A
transformer has a primary winding of 600 turns and a secondary winding of 150
turns. When the load current on the secondary is 60 A at 0.8 power factor
lagging. Determine the no-load current of the transformer and its phase with
respect to the voltage.
Q:-9
Derive emf equation
for a single phase transformer. A 25 kVA, 2200/220 V, 50 Hz. 1-phase
transformer has following parameters R1 = 1.75 Ω, R2 = 0.0045 Ω, X1 = 2.6 Ω, X2
= 0.0075 Ω. Calculate: Equivalent resistance referred to primary and secondary.
Q:-10
A 100 kVA, 1100/220
V, 60 Hz transformer has a high-voltage winding resistance of 0.1 Ω and a
leakage reactance of 0.3 Ω. The low-voltage winding resistance is 0.004 Ω and
the leakage reactance is 0.012 Ω. The source is applied to high-voltage side.
(i) Find the equivalent winding resistance and reactance referred to the
high-voltage side and low-voltage side. (ii) Compute the equivalent resistance
and equivalent reactance drops in Volts and in per cent of the rated winding
voltages expressed in terms of the primary quantities. (iii) Calculate equivalent
leakage impedances of the transformer referred to the primary and secondary
sides.
Q:-11
A 20 kVA, 2000 V/200
V, single phase 50 Hz transformer has a primary resistance of 1.5 Ohm and a
reactance of 2 Ohm. The secondary resistance and reactance are 0.015 Ohm and
0.02 Ohm respectively. The no load current of transformer is 1 A at 0.2 power
factor. Determine: (i) Equivalent resistance, reactance and impedance referred
to primary (ii) Total copper loss. (iii) Draw approximate equivalent circuit.
Q:-12
A voltage v = 200
sin 314 t is applied to the transformer winding in a no-load test. The
resultant current is found to be i = 3 sin (314 t – 60°). Determine the
core-loss and the parameters of no-load approximate equivalent circuit.
Q:-13
What is the
significance of turn ratio in transformer? The maximum efficiency of a 100 kVA
transformer is 98.40% and operates at 90% full load unity power factor.
Calculate the efficiency of transformer at unity power factor at full load.
Q:-13
Explain the
operation of single phase transformer at load. A single phase 10 kVA, 11000 /
220 V transformer has core loss 300 W at rated voltage and copper loss 400 W at
full load. Find the efficiency of transformer feeding to a load 8 kVA at 0.8
p.f. lagging. What will be the maximum efficiency of the transformer?
Q:-14
A single phase 100
kVA, 6.6 kV/230 V, 50 Hz transformer has 90% efficiency at 0.8 lagging power
factor both at full load and also at half load. Determine iron and copper loss
at full load for transformer.
Tuesday, 18 October 2016
Selected Problems (long and Medium) For REE-101
Selected Problems (long and Medium) For REE-101
UNIT-I
Q:-1 State and prove maximum power
transfer theorem.
Q:-2 What is the criterion for star –
delta transformation? Develop the relationship for delta to star and star to
delta transformation.
Q:-3 Draw V-I characteristic of
voltage and current sources. Explain source transformation theory in a circuit.
UNIT-II
Q:-1 What are the causes of low power
factor in supply system? Discuss its effect & how power factor can be improved?
Q:-2 Derive resonance condition in
series circuit. Also derive the expression for Bandwidth.
Q:-3 Derive resonance condition in
parallel circuit. Also derive the Quality Factor of the Parallel RLC Circuit at
resonance.
UNIT-III
Q:-1 Derive the relation between line
voltage and phase voltage in three-phase delta connected circuit..
Q:-2 Derive the relation between line
voltage and phase voltage in three-phase star connected circuit. Also derive
the expression for power.
Q:-3 With
the help of connection diagram and the related phasor diagram show that W1 + W2 gives the
total 3-phase power in a
two wattmeter method of power measurement and determine the active three phase
power and load power factor.
Q:-4 Draw and explain the working of
attraction type moving iron instrument.
Q:-5 Derive the torque equation and
explain the working of repulsion type moving iron instrument.
Q:-6 Explain the PMMC instrument.
Also derive the expression for deflected torque.
Q:-7 Explain the construction and
working of Electrodynamics type instrument with diagram.
UNIT-IV
Q:-1 What is B-H curve? Also explain
the hysteresis and eddy current loss.
Q:-2 Explain the analogy between
electric and magnetic circuit with AC excitation.
Q:-3 Explain the working of a
transformer with the derivation of the emf equation for a transformer. Also
discuss the losses in the transformer.
Q:-4 Derive the condition for maximum
efficiency for a Transformer.
Q:-5Explain single phase auto
transformer and give its two applications.
UNIT-V
Q:-1 Derive the expression for EMF
equation for a DC machine.
Q:-2 Draw the characteristics of DC
series motors.
Q:-3 Derive the expression of torque
for dc motor. Also discuss the characteristics of dc shunt motor.
Q:-4 Why a three phase synchronous
motor is not self starting? Discuss use of damper winding for starting a
synchronous motor.
Q:-5 Explain the slip-torque
characteristics of three phase induction motor.
Q:-6 Explain with the help of
diagrams, how a rotating field is produced in the air gap of a three-phase induction motor.
Q:-7 Using double field revolving
theory, explain why single phase induction motor is not self starting? Describe
capacitor start- capacitor run method for starting single phase induction motor
and give any two application of such motor.
Selected Short Question On REE-101
Selected Short Question On REE-101
Unit-I
Q:-1Define Bilateral & Unilateral
Elements with example.
Q:-2 Distinguish between active and passive
elements.
Q:-3 Define Ideal Voltage and Current
source.
Q:-4 If resistance of each branch is 3Ω in a
delta connected load, what would be the resistance of each branch in its star
equivalent?
Q:-5 Explain source transformation principle
in any circuit.
Q:-6 What do you mean by term Effective or RMS value.
Q:-7 Define Form Factor and peak factor.
Unit-II
Q:-1 What do you mean by term power factor?
Q:-2 What do you mean by the term Resonance?
Q:-3 What are the common conditions of both the series and parallel
resonance?
Q:-4 What do you mean by the term “Reactive Power”?
Q:-5 What do you meant by Current
Magnification factor?
Q:-6 What do you meant by Voltage
Magnification factor?
Unit-III
Q:-1 In Dynamometer type wattmeter is used
for measuring .
Q:-2 In Permanent Magnet Moving coil
instrument is used for measuring .
Q:-3 Attraction type moving iron instrument
have scale.
Q:-4 Why two-wattmeter method for power
measurement is universal one?
Q:-5 What is the major difference between
PMMC type and dynamometer type of instruments?
Q:-6 Enlist the types of moving iron
instrument.
Q:-7 What do you mean
by terms “shunt” and “ multiplier”..
Q:-8 What are the different torques required in an
indicating type instruments?
Q:-9 Why is scale of
moving iron instrument is nonlinear?
Unit-IV
Q:-1 What is magneto motive force and write
its unit.
Q:-2 Define the flux density as applied to
magnetic circuit.
Q:-3 Define the Reluctance as applied to
magnetic circuit.
Q:-4 Define the permeability as applied to
magnetic circuit.
Q:-5State the dot convention for mutually
coupled coils in terms of flux direction.
Q:-6 The full load copper-loss and iron-loss
of a transformer are 6400 W and 5000 W respectively. The above losses at half
load are .
Q:-7 What do you understand by the term
“ideal transformer”? Why the efficiency of transformer is high as compared to
other machines?
Q:-8 If in a single phase transformer core,
hysteresis and eddy current losses are 80 W and 50 W at normal voltage and
frequency then calculate losses when voltage and frequency are increased by
20%.
Q:-9
What is the condition for transformer maximum
efficiency?
Q:-10 A 400/200V single phase transformer has
primary winding resistance 1 ohm and secondary winding resistance 0.2 ohm. What
will be total resistance of transformer referred to primary side?
Unit-V
Q:-1 Name two motors used for constant speed
operation.
Q:-2 Which motor is preferred in elevators
and why?
Q:-3 Mention the applications of dc series
motor.
Q:-4 Explain the term “slip” in induction
motor.
Q:-5 Write the name of different types of
rotor of an alternator.
Q:-6 Why Dc series motor cannot be started
at no load?
Q:-7 How will you change the direction of
rotation of three phase motor?
Q:-8What are the different methods of
starting of single phase induction motor?
Subscribe to:
Posts (Atom)