(dee 411) - anucdedee 411) b.tech. degree ... derive an expression for the fault current for a line...

(DEE 411)

B.Tech. DEGREE EXAMINATION, DECEMBER 2012

(Examination at the end of Fourth Year First Semester)

Electricals and Electronics Engineering

Paper I — INDUSTRIAL MANAGEMENT

Time : Three hours Maximum : 75 marks

Answer Question No.1 is compulsory

and any FOUR from the remaining

All questions carry equal marks

1. Write short notes on :

(a) Management Science.

(b) Public limited companies.

(c) Equivalent cash flow diagram.

(d) Declining balance method.

(e) Acceptance sampling.

(f) Job analysis.

(g) Market Research.

2. Explain the private limited and public limited companies.

3. State the channels employed in the management of distribution of industrial goods.

4. Write short notes on the following :

(a) The straight line method.

(b) The annual equivalent method.

5. Enumerate the principles of Scientific management.

6. Explain the product analysis and value analysis.

7. Briefly explain the X, P, R and C charts.

8. Describe the significance of inventory management.

9. Explain the functions of Marketing and product life cycle.

——————

(DEE 412)




Paper II — POWER SYSTEMS OPERATION AND CONTROL


Answer Question No.1 compulsorily. (15 × 1 = 15)

Answer any ONE question from each Unit. (4 × 15 = 60)

1. (a) What do you understand by incremental fuel rate?

(b) Write the condition for optimum operation.

(c) What are the units of heat rate curve?

(d) Draw the cost curve.

(e) Define Penalty factor.

(f) What are the current distribution factors?

(g) Define the Regulation.

(h) Define Control Area.

(i) Define Parallel frequency regulation.

(j) What is the range of Time Constant Tt?

(k) What are the objectives of the load compensator?

(l) What is load compensation?

(m) What are the advantages of series compensation?

(n) What are the limitations of loading capability?

(o) What is the purpose of synchronous phase modifier?

UNIT I

2. (a) Explain how the incremental producted cost of a thermal power station can be

determined?

(b) Explain the various factors to be considered in allocating generation to different

power stations for optimum operation.

Or

3. (a) Discuss and define the loss formula coefficients.

(b) What is the objective in economic sheduling?

UNIT II

4. With a neat block diagram explain the load frequency control for a single area

system.

Or

5. (a) Explain the necessity of maintaining a constant frequency in power system

operation.

(b) Two generators rated 300 MW and 600 MW are operative in parallel. Their

governors have a droop characteristics of 4% and 5% respectively from no load

to full load. Assuming that the generators are operating at 50 Hz at no load,

determine how would a load of 750 MW be shared between them. What will be

the system frequency at this load? Assume free governor action.

UNIT III

6. (a) With a neat phasor diagrams explain the reactive power balance and its effect

on system voltage.

(b) Compare the technical advantages of static compensator over synchronous

condenser.

Or

7. (a) Explain briefly about the shunt and series compensatin of transmission

systems.

(b) Write short notes on STATCOM and FACTS devices.

UNIT IV

8. Discuss the hardware and software of power system control center.

Or


(a) Power system and dispatch training simulator.

(b) Evolution of power system control technology.

——————

(DEE 413)




Paper III — INDUSTRIAL DRIVES


Answer Question No.1 compulsorily (15 × 1 = 15)

Answer ONE question from each Unit (4 × 15 = 60)

1. Write briefly on the following :

(a) Name the types of electric drives.

(b) What are the advantages of electric drive?

(c) What are the classification of load torques?

(d) What is cycloconverter?

(e) What is braking?

(f) What do you mean by load equalisation?

(g) List any two drawbacks of ward Leonard scheme.

(h) Draw the speed-torque characteristics of DC shunt motor.

(i) Give any two applications of eddy current drives.

(j) Why is starting method required for DC motor?

(k) What is starting?

(l) Explain the eddy current drives.

(m) What is the difference between Wound field and Permanent magnet motor?

(n) Explain the active load torque.

(o) Draw the Schematic diagram of variable speed constant frequency generation.

UNIT I

2. (a) Explain the components of electric drives.

(b) Explain the Fundamental torque equations of electric drives.

Or

3. (a) Discuss the modes of operation of electric drives.

(b) Explain the closed loop control of drives.

UNIT II


(a) Methods of braking.

(b) Methods of armature voltage control.

Or

5. (a) Explain the control of separately excited DC motors.

(b) A 200 V, 10.5 A, 2000 rpm shunt motor has the armature and field resistances

of 0.5 Ω and 400 Ω respectively. It drives a load whose torque is constant at

rated motor torque. Calculate motor speed if the source voltage drops to 170 V.

UNIT III

6. Briefly explain the rotor resistance control and slip power recovery.

Or

7. (a) Explain the principle and applications of variable speed and constant frequency

generation scheme.

(b) Explain the pole amplitude modulation.

UNIT IV


(a) Synchronous variable speed drives.

(b) Braking of synchronous motor.

Or

9. (a) Describe the principle of operation of a switched reductance motor drives.

(b) Explain the principle of operation of a stepper motors.

——————

(DEE 414) B.Tech. DEGREE EXAMINATION, DECEMBER 2012



Paper IV — POWER SYSTEM ANALYSIS AND STABILITY



Answer ONE question from each Unit. (4 × 15 = 60)

1. (a) Define per unit impedance.

(b) What are the advantages of per unit quantities?

(c) Define the load flow problem.

(d) How do you classify the buses in power system?

(e) Draw the per unit equivalent circuit of single phase transformer.

(f) What are the different types of load representations?

(g) State Thevenin’s theorem.

(h) Define “Operator a”.

(i) Write the expression for voltage at LG fault.

(j) Define critical clearing angle.

(k) What are open conductor faults?

(l) What are the different types of series faults?

(m) What is the relation between zero sequence impedance and positive sequence

impedance for a fully transposed transmission line?

(n) What is the importance of Zbus?

(o) What is the multiplying factor for air breakers rated 600 V (or) lower?

UNIT I

2. (a) Give the significance of single line diagram.

(b) Three generators are rated as follows :

Generator 1: 100 MVA, 33 kV, reactance 10%



Determine the reactance of the generators corresponding to base values of 200

MVA and 35 kV.

Or

3. (a) Explain briefly the representation of loads.

(b) A 120 MVA, 19.5 kV generator has xs = 1.5 p.u. and is connected to a

transmission line by a transformer rated 150 MVA, 230 kV Y/Y with x = 0.1 p.u.

If the base to be used in the calculation is 100 MVA, 230 kV for the

transmission line, find the per unit values to be used for the transformer and

generator reactances.

UNIT II

4. (a) Explain the formulation of ybus of a network by direct inspection with an

example.

(b) Derive the basic equation for load flow studies and also write the assumption

and approximation to get the simple equations.

Or

5. (a) Explain the necessity of load flow studies in power system.

(b) Explain the need for short circuit studies.

UNIT III

6. (a) Draw the relationship between the phase components and the sequence

components.

(b) Explain the term maximum momentary short circuit current.

Or

7. (a) Find the fault current when an L-L-G fault occurs at the terminals of an

unloaded generator.

(b) Derive an expression for the fault current for a line to ground fault.

UNIT IV

8. (a) State the bad effects of instability. Distinguish between steady state and

transient stabilities.

(b) Write short notes on the assumptions made in deducing equal area criterian

and validity of the assumptions.

Or

9. (a) Derive the power angle equation of a multi machine system.

(b) A generator operating at 50 Hz delivers 1 p.u. power to an infinite bus through

a transmission circuit in which resistance is ignored. A fault takes place

reducing the maximum power transferable to 0.5 p.u. Whereas before the fault,

this power was 2.0 p.u. and after the clearance of the fault, it is 1.5 p.u. by the

use of equal area criterion, determine the critical clearing angle.

——————

(DEE 415)




Paper V — ELECTRICAL MACHINE DESIGN



Answer any ONE question from each Unit. (4 × 15 = 60)

1. (a) Write the emf equation of a DC motor.

(b) Define specific electric loading.

(c) List the main dimensions of a DC machine.

(d) What is the effect of Fractional pitch?

(e) If a DC machine is having 6 poles, what is the number of inter poles?

(f) What is retrogressive winding?

(g) List out the cooling methods available for transformer cooling.

(h) Why the ore is laminated?

(i) On what factors, number of Rotor slots is dependent.

(j) What is the mathod used for inter turn insulation of stator winding?

(k) Write the output equation of a synchronous machine.

(l) How many slip rings are to be provided to a Slip Rip IM and why?

(m) How flux density effects the back iron width?

(n) How length of the conductor in a coil is calculated?

(o) Define slip of induction motor.

UNIT I

2. (a) How the effects of armature reaction are minimized?

(b) A 350 kW, 500 V, 450 rpm, 6 pole, DC generator is built with an armature

diameter of 0.87 mts and a core length of 0.32 mts. The lap wond armature has

660 conductors. Calculate the specific electric and magnetic loading.

Or

3. (a) Give the Interpole design of a DC machine.

(b) Calculate the main dimensions of a 60 W, 6 pole, 800 rpm dc generator from the

following data :

Bav = 0.6 T ; ac = 400 ac per metre.

Pole Arc/Pole pitch is 068 ;

Efficiency : 0.8 ;

Core length / Pole pitch = 0.75.

UNIT II

4. (a) Explain the procedure to design the window of the core of a transformer.

(b) A 3 phase, 50 Hz, oil cooled core type transformer has the following dimentions

:

Distance between core centres : 0.2 mts

Height of window : 0.24 mts

Dia of circumscribing circle : 0.14 mts

The flux density in the core is 1.25 wb/mts2.

Current density is 2.5 A/mm2

Estimate the KVA rates. Assume window space fach 0.2; Core area factor 0.56

and core is two stepped.

Or

5. (a) Write a short notes on the design of cooling schemes of a transformer.

(b) Calculate the core and window areas required for a 1000 KVA, 6600/400 V, 50

Hz, single phase core type transformer. Assume max. flux density 1.25 wb/m2

and a current density of 2.5 A/mm2. Voltage per turn is 30 V and window space

factor : 0.3.

UNIT III

6. (a) Derive the output equation of a 3-phase induction motor.

(b) A 5 hp; 440 V, 3 phase, 4 pole IM with 375 turns per phase in the stator has the

following design data :

Rotor slots = 30 ;

Rotor bar size = 8.5 × 6 mm2

Length of each bar : 0.125 mts.

End ring size = 10 × 15 mm2

Mean dia of the ring (end) = 0.125 mts

The bars and end rings are of copper with resistivity 0.021 Ω/m and mm2 at the

working temperature. Calculate the rotor resistance referred to stator winding.

Or

7. (a) Discuss the design procedure tor squirrel case rotor of as 3-phase Induction

motor.

(b) Find the main dimensions of 15 kW, 3 phase, 400 V, 50 Hz, 2810 rpm. Case

induction motor has an efficiency of 0.88 and FL power factor of 0.9. Assume sp.

Magnetic loading 0.5 wb/m2; sp. Electric loading 25000 A/m, rotor peripheral

speed is 20 m/s approx. at synchrons speed.

UNIT IV

8. (a) Give the detailed procedure to design the field system of a synchronous

machine.

(b) Explain the advantages of CAD.

Or

9. (a) Explain the design of rotor windings of a synchronous machine (non-saliant

pole).

(b) Give the algorithm used to implement computer aided design to a transformer.

——————

(DEE 416/B)




Paper VI — HVDC TRANSMISSION




1. Write briefly on the following :

(a) Draw the block diagram of HUDC system.

(b) Define the surge impedance loading for a Transmission line.

(c) Give any four advantages of HUDC transmission.

(d) Give any two disadvantages of HUDC transmission.

(e) What are the types of DC links?

(f) List any two applications of DC transmission.

(g) Write the expression for the current rating of a thyristor value.

(h) Define the term ‘utilization factor’.

(i) Define the term ‘peak inverse voltage’.

(j) Mention any two drawbacks of IPC scheme.

(k) Draw the block diagram of power and auxiliary controller.

(l) Write the expression for direct current flowing through the DC link from

rectifier to the inverter.

(m) Draw the characteristics of converters in Vd, Id plane.

(n) Draw the impedance characteristics of double tuned filter.

(o) List the basic firing schemes.

UNIT I

2. (a) Explain modern trends in DC transmission.

(b) What is the need for interconnection of the systems?

Or

3. (a) With neat sketches explain the different kinds of DC links available.

(b) Compare AC and DC transmission system based on economic aspects and

technical performance and reliability.

UNIT II

4. Draw a Schematic of a 6 pulse converter circuit and derive from fundamentals, the

expression for voltage and currents for the operation of converter as a rectifier and

inverter with relevant wave forms.

Or

5. (a) Discuss the various converter faults in detail.

(b) A bridge connected rectifier is fed from 230 kV/110 kV transform with primary

connected to 230 kV. Determine the dc output voltage when the commutation

angle is 16º and the delay angle (i) 0°, (ii) 15° and (iii) 40°.

UNIT III

6. Explain the following :

(a) Firing angle control.

(b) Current and extinction angle control.

Or

7. (a) Discuss the AC and AG operating modes of DC link in detail.

(b) Explain the basic principle of DC link control characteristics.

UNIT IV

8. (a) Obtain a mathematical model of a DC link.

(b) Draw the flowchart of AC/DC load flow.

Or

9. (a) Explain characteristic and non-characteristics of harmonics.

(b) What are the various types of filters that are employed in HUDC converter

stations? Discuss them in detail.

——————

(DEE 416/D)

B.Tech. DEGREE EXAMINATION, DECEMBER 2012.


Electrical and Electronics Engineering

Paper VI — FUZZY LOGIC AND APPLICATION


Answer Question No. 1 compulsorily. (15)


1. (a) Define uncertainty. (2)

(b) Define cardinality. (2)

(c) Define fuzzification. (2)

(d) Explain the fuzzy vectors. (3)

(e) Explain the fuzzy tautogies. (2)

(f) What is cluster validity? (2)

(g) What is FCM? (2)

UNIT I

2. (a) Explain the properties of classical sets.

(b) Explain the fuzzy set operations.

Or

(c) Write short notes on the following :

(i) Non interacting fuzzy sets

(ii) Tolerance and equivalence relations.

UNIT II

3. (a) Write short notes on the following :

(i) Futures of membership functions

(ii) Angular fuzzy sets.

Or

(b) Explain the fuzzy arithmetic and fuzzy arithmetic.

(c) Explain DSW algorithm.

UNIT III

4. (a) Explain the classical predicate logic – Tauologies.

(b) Explain the deductive inferences.

Or

(c) Write short notes on the following :

(i) Decomposition of compound rules

(ii) Aggregation of fuzzy rules.

UNIT IV

5. (a) Explain the fuzzy synthetic evaluation.

(b) Explain the fuzzy Bayesian decision method.

Or

(c) Explain the Hardening the fuzzy c-partition.

(d) Explain the similarity relations from clustering.

–––––––––––

(DEE 421)


(Examination at the end of Fourth Year Sixth Semester)


Paper I — ELECTRICAL POWER DISTRIBUTION SYSTEM ENGINEERING


Answer Question No.1 compulsorily (15 × 1 = 15)

Answer ONE question from each Unit (4 × 15 = 60)

1. (a) What is meant by load factor?

(b) What is meant by contribution factor?

(c) What is load curve?

(d) What is loss factor?

(e) What are the different types of distribution transformers employed in overhead

distribution systems?

(f) Write the expression for Regulation of distribution transformer.

(g) What is a distribution system?

(h) List out any two advantages of Radial type feeders.

(i) What is transformer load management?

(j) Define automatic circuit reclosures.

(k) Explain the powerfactor correction.

(l) Explain the secondary banking.

(m) Define voltage spread.

(n) Define the efficiency of distribution transformers.

(o) What are the factors which effect the selection of primary feeder rating?

UNIT I

2. Draw the Schematic view of distribution system planning and explain the role of

computer in distribution system planning.

Or

3. (a) Explain how load growth is estimated. How is diversified maximum demand is

computed? Illustrate with an example.

(b) Find the annual load factor and average demand given that peak load is 3.5

MW units supplied 10 million.

UNIT II

4. (a) Explain the kW-kVA method of determining regulation of a distribution

transformer.

(b) Explain the different types of distribution transformers in detail.

Or


(a) Substation bus schemes.

(b) Sub-station location and rating.

UNIT III

6. (a) Compare the Radial and loop type primary feeders.

(b) What are the various factors that influence the primary feeder loading?

Or

7. (a) What are the over current protective devices applied to distribution systems?

Explain any one.

(b) Explain the Reclosure to circuit breaker co-ordination.

UNIT IV

8. (a) Derive the expressions for voltage drop and power loss for radial feeders with

uniformly distributed load.

(b) Explain the effect of shunt compensation on distribution system.

Or


(a) Line drop compensation.

(b) Economic justification for capacitors.

——————

(DEE 422)


(Examination at the end of Fourth Year Sixth Semester)


Paper II — HIGH VOLTAGE ENGINEERING




1. (a) Write output expression for a multistage impulse generator.

(b) Draw the basic circuit of impulse current generator.

(c) Differentiate wave shape control resistors.

(d) Explain the term ‘Tesla Coil’.

(e) What are the standard specifications of impulse generation currents?

(f) What is the application area of impulse generator?

(g) List out atleast two applications of each voltage divider.

(h) What are the limitations of generating voltmeters?

(i) What is the function of high speed oscilloscope?

(j) Define wavelet.

(k) Define withstand voltage.

(l) Why wavelets are used for fault detection?

(m) What is the purpose of bushings?

(n) What is the function of an isolator?

(o) What is the basic principle of finite difference method?

UNIT I

2. Define the terms (a) Impulse voltages, (b) Chopped wave, (c) Impulse flashover

voltage, (d) Impulse puncture voltage, (e) Impulse ratio for flashover, (f) Impulse

ratio for puncture.

Or

3. Explain with neat sketches Cockroft – Walton voltage multiplier circuit. Explain

clearly its operation when the circuit is (a) unloaded, (b) loaded.

UNIT II

4. (a) What are the requirements of a sphere gap for measurement of high voltages?

Discuss the disadvantages of sphere gap for measurements.

(b) An obsolute electrostatic voltmeter has a movable circular plate 8 cms in

diameter. If the distance between the plates during a measurement is 4 mm,

determine the potential difference when the force of attraction is 0.2 gmwt.

Or

5. (a) Explain Peak voltmeter with the help of neat diagrams.

(b) Describe the layout of high voltage lab.

UNIT III

6. (a) Describe the arrangement of insulators for performing various tests.

(b) List out various tests to be carried out an insulator and give a brief account of

each test.

Or

7. (a) Explain briefly various tests to be carriedout on a bushing.

(b) Explain briefly the use of wavelets for fault detection.

UNIT IV


(a) Finite difference method. (b) Finite element method.

Or


(a) Boundary element methods. (b) Charges simulation methods.

——————

(DEE 423) B.Tech. DEGREE EXAMINATION, DECEMBER 2012.

(Examination at the end of Fourth Year Sixth semester)


Paper III — COMPUTER AIDED POWER SYSTEM ANALYSIS


Answer Question No. 1 compulsory. (15 × 1 = 15)


1. (a) Define co-tree.

(b) State KVL.

(c) What is a primitive network?

(d) Define non-singular transformation.

(e) Write the expression for symmetrical short circuit current.

(f) Define load flow solution.

(g) What are the necessities for load flow studies?

(h) Mention any two assumptions made for modifying bus admittance matrix with

mutual coupling.

(i) Mention any three advantages of Newton-Raphson method.

(j) Define acceleration factor.

(k) Define the term stability.

(l) Define transient stability.

(m) Define critical clearing angle.

(n) What is the difference between large and small disturbances?

(o) What is sparsity of a matrix?

UNIT I

2. Define the incidence matrices KCCBBA ,ˆ,,ˆ,, and verify the following relations for

the network shown in fig. Take 1 as ground bus

(a) tlb Bc −=

(b) UBC t=ˆˆ

(c) UKAA tbcb =

(d) tll KAB = .

Or

3. (a) Derive the bus admittance matrix by singular transformation.

(b) Obtain the admittance matrix for a primitive network with mutual coupling

with an example.

UNIT II

4. Derive the necessary expressions for the building of busz when

(a) New element is added creating a new bus

(b) New element is added between two existing buses. Assume mutual coupling

between the added element and with the elements in the partial network.

Or

5. (a) Briefly explain fault level of a bus, hence justify infinite bus as a constant

voltage source.

(b) Two motors each of IMUA at 440 volts with 0.1 pu transient reactance are

connected in parallel. The motors are fed over a short line of reactance 0.05 Ω .

This live in supplied from a large system whose short circuit MUA is 8 on 440

volts rating. It a ϕ3 short circuit occurs at the terminals of motors. Calculate

the short circuit current fed into the fault.

UNIT III

6. (a) Explain the necessity of load flow studies in power systems.

(b) Describe Newton Raphson method in polar coordinates.

Or


(a) Data for power flow studies

(b) Merits and demerits of using polar and rectangular coordinates in load flow

studies.

UNIT IV

8. (a) Define the following terms :

(i) Steady state stability limit

(ii) Dynamic stability limit

(iii) Transient stability limit.

(b) List the assumptions made on the transient stability solution techniques.

Or

9. (a) Discuss the state equation for steady state stability of power systems with

single machine connected to infinite bus using swing equation for the machine.

(b) Give the list of methods to improve transient stability of the systems.

–––––––––––

(DEE 424/A)


(Examination at the end of Fourth Year

Sixth Semester)


Paper IV — EMBEDDED SYSTEMS AND VLSI


Answer Question No. 1 compulsorily. (15)


1. (a) Explain the set processors. (3)

(b) What is sequential logic? (2)

(c) What is sheet resistance? (2)

(d) What is Gate logic? (2)

(e) What is stick diagram? (2)

(f) What is RT synthesis? (2)

(g) What are the applications of single purpose processors? (2)

UNIT I

2. (a) Write short notes on the following :

(i) RT-level combinational logic

(ii) Trade–offs.

Or

(b) Explain the programmer’s view.

(c) Explain the micro controllers and digitals signal processors.

UNIT II

3. (a) Discuss MOS technology and BIMOS technology.

(b) List the electrical properties of BIMOS circuit.

Or

(c) Explain the scaling of MOS circuits.

(d) Explain the delay units.

UNIT III

4. (a) Explain the examples of structured design.

(b) Write short note on memory resistors.

Or

(c) Explain the FPGAs.

(d) Explain the design approach.

UNIT IV

5. (a) Explain the synthesis.

(b) Explain the parallel evolution of compilation and synthesis.

Or

(c) Explain the following :

(i) Behavioral synthesis

(ii) Reuse of intellectual property coder.

——————

(DEE 424/B)


(Examination at the end of Fourth Year sixth Semester)


Paper IV — ARTIFICIAL NEURAL NETWORKS


Answer questions No.1 Compulsory (15)

Answer ONE question from each unit (4 × 15 = 60)

1. (a) What is Statistical learning theory. (3)

(b) Define ANN and neural computing (2)

(c) What is a Hessian matrix? (2)

(d) What is a linear least square filters? (2)

(e) What is meant by Generalized RBF networks? (2)

(f) What is contextual maps? (2)

(g) What is a Associative memories? (2)

UNIT I

2. Write short notes on the following:

(a) Memory based learning.

(b) Error correction learning.

Or

3. (a) Explain the competitive learning.

(b) Discuss network architectures.

UNIT II

4. (a) Explain Adaptive filtering problem.

(b) Explain Annearling techniques.

Or

5. (a) Explain XOR problem.

(b) Explain cross validation network pricing techniques.

UNIT III

6. Write short notes on the following

(a) Covers theorem on the separability of patterns.

(b) Regularizartion theory.

Or

7. Write short notes on the follwoing

(a) Approximation properties of RBF networks.

(b) Comparison with multilayer perceptions.

UNIT IV

8. (a) Explain the self-organizing maps.

(b) Explain the learning vector quantilization.

Or

9. (a) Explain the applications in speech and image processing.

(b) Explain the direct applications of ANN.

–––––––––––

(dee 411) - anucdedee 411) b.tech. degree ... derive an expression for the fault current for a line...

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