Master Data_2014 Batch
1st log in ur Gmail account . then click on "Send button"
(Site best viewed in chrome & Firefox Web Browser)
IED (Imp Questions)
INRODUCTION TO ELECTRIC DRIVES
Assignment 5
1. Describe static kramer drive and show that the steady
state torque is not influenced by
whether a transformer is used or not. Derive appropriate
expressions to obtain torque-speed
characteristics of ststic kramer drive.
2. Enumerate the various methods od speed control of 3-phase
induction motor ehem fed through
semiconductor devices.
3. Descibe the regenerative braking of a chopper fed
seperately excited DC motor. Illustrate
answer with circuit diagram and relevant waveforms.
4. The speed of a seperately-excited dc motor is controlled
through 1-phase half wave controlled
converter from 230V mains. The motor armature resistance is
0.5 ohms and motor constant
is K = 0.4 V-s/rad. For load torque of 20Nm at 1500 rpm and
for constant armature current,
calculate:
i) Firing angle of the coverter
ii) Rms value of thyristor current
iii) i\p power factor of motor
5. Explain the cocept of step down cyclocoverter. Enumerate
the advantages and applications of
cycloconverter.
6. Give the differences between 180 and 120° modes of
3-phase with relevant waveforms of phase
and line voltages.
7. Explain three-phase half controlled full wave rectifier
with desired waveforms.
8. Derive the expression of a 1-hase full wave bridge rectifier
fully controlled for R-L-E load.
9. An armature (RLE load) of a seperately dc motor is fed
from 1-phase full wave fully controlles
covereter. The supply ac voltage V= 220V, Ra = 0.06 ohms, La
=0.085 mH, Ia=150A, speed = 875
rpm, Va = 200V. Find the output voltage and α for a rated
load when :
i)E = 160V (speed =
733 rpm, 1st quadrant)
ii)E = -190V (speed =
-500 rpm, 4th quadrant )
10. What are ac drives? Give merits and demerits of ac
drives with respect to dc drives.
11. Define speed control od induction motors. Define method
of resistance control.
12. Explain basi machine equations. Define DC motor speed
control .
13. Explain single phase full wave bridge converter. Also
explain three phase bridge inverter.
14. Draw the circuit diagram and explain the working of slip
power recovery system using ststic
Scherbius drive and also draw the torque-speed
characteristics.
15. What is the basic principle of operation of an induction
motor, Explain it with reference to
equivalent circuit.
16. What is Jones chopper? Explain with its voltage and
current waveforms.
Microwave (Imp Questions)
COLLEGE ROLL NO:………………..
DRONACHARYA GROUP OF INSTITUTIONS, G.NOIDA.
SESSION- 2011-2012
Microwave Engineering (EEC 603)
ASSIGNMENT 2
1)
A signal of
power 28 MW is fed into one of the collinear ports of lossless H-plane Tee.
Find the power in the remaining ports when other ports are terminated by means
of matched loads.
2)
In an H-plane Tee junction, 20 MW power is applied to
port 3 which is perfectly matched. Find the power delivered to the load 60 Ω
and 75 Ω converted to Port 1 & 2.
3)
Explain waveguide Tee in detail & find out S-
Matrix of each Tee.
4)
Explain Microwave propagation in ferrites.
5)
Explain Microwave circulators.
6) Explain
Microwave isolators.
ASSIGNMENT 4
1)
Explain
construction & operation of TWT.
2)
Explain mode of operation of microwave BJT.
3)
Explain hybrid π-model of BJT.
4)
Explain VI charters tics of JFET & also define
boundary condition .
5)
Explain small signal equivalent circuit of GaAs MESFET.
6)
A reflex Klystron operates under the following
condition : V0= 500v , Rsh= 20 KΩ, n=2 , fr=8 GHz , L= 1 mm is the spacing b/w repeller and
cavity .
i) Value of repeller voltage
ii) Direct current necessary to give microwave gap voltage of 200V.
iii) Electronic efficiency .
i) Value of repeller voltage
ii) Direct current necessary to give microwave gap voltage of 200V.
iii) Electronic efficiency .
ASSIGNMENT 5
1)
A typical
n-channel GaAs MESFET has the following parameters Electron concentration N = 8 x 10
cm , channel height a=0.1 µm ,
relative dielectric constant εr ,
Channel length L= 14 µm , Channel
width Z=36 µm, Electron mobility µ = .o8
m2/V.s , Drain voltage V
d = 5 volts , Gate voltage
Vg= -2 volts , Saturation drift velocity Vs = 2x 105 m/s
a) Calculate the pinch off voltage .
b) Compute the velocity ratio
c) Determine the saturation current at Vg = 0 ,
d) Find the Drain Current .
a) Calculate the pinch off voltage .
b) Compute the velocity ratio
c) Determine the saturation current at Vg = 0 ,
d) Find the Drain Current .
2)
A Two Cavity Klystron operates under the following
condition : V0= 900v , I0= 30 mA, d= 1 mm cavity , Rsh= 49 GΩ, n=2
, f=8 GHz , L = 4 mm . Find
i) The electron velocity
ii) The input voltage for maximum output voltage ,
iii) The dc transit time of electron
iv) voltage gain in db.
i) The electron velocity
ii) The input voltage for maximum output voltage ,
iii) The dc transit time of electron
iv) voltage gain in db.
3)
Explain the
Tunnel Diode.
4)
Explain the Backward Wave Oscillator.
microwave assignment no. 2
COLLEGE ROLL NO:………………..
DRONACHARYA GROUP OF INSTITUTIONS, G.NOIDA.
SESSION- 2011-2012
Microwave Engineering (EEC 603)
ASSIGNMENT 2
1)
A signal of
power 28 MW is fed into one of the collinear ports of lossless H-plane Tee.
Find the power in the remaining ports when other ports are terminated by means
of matched loads.
2)
In an H-plane Tee junction, 20 MW power is applied to
port 3 which is perfectly matched. Find the power delivered to the load 60 Ω
and 75 Ω converted to Port 1 & 2.
3)
Explain waveguide Tee in detail & find out S-
Matrix of each Tee.
4)
Explain Microwave propagation in ferrites.
5)
Explain Microwave circulators.
6) Explain
Microwave isolators.
Subscribe to:
Posts (Atom)