COURSE PLANNER. B.E. 3 rd YEAR [ 6 TH SEMESTER] Class: Electrical TERM: 16/2 (DEC-16 TO MAY-17)

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1 COURSE PLANNER SUBJECT: UTILIZATION OF ELECTRICAL ENENRGY AND TRACTION (21609) B.E. 3 rd YEAR [ 6 TH SEMESTER] Class: Electrical TERM: 16/2 (DEC-16 TO MAY-17) Faculty: PROF. T. S. GAJJAR PROF. R. M. DESAI PROF. U. V. VYAS PROF. J. P. TOPIWALA Contents: 1. Course Outcomes 2. Course Contents[Syllabus] 3. List of Reference Books 4. List of Open source software and learning websites required for experiments 5. Active Learning Assignments and Tutorial. Instructions: [1]This set of Assignment-Tutorial consist the collection of questions of past GTU Question papers. [2]Students should make a separate Chapter wise Files [write on File Pages only] to solve these Questions. [3]Students must solve these given set of Assignments by themselves only. [4]Assessment of given assignment should be done regularly after completion of each chapter by Students from the respective faculty members. 1

2 [1]COURSE OUTCOME (CO): After learning the course, the students should be able to: 1. Understand the power electronics technology in efficient utilization of electrical power 2. Apply power electronics technology in efficient utilization of electrical power 3. Analyze effective utilization of Power Electronic Technologies in Electrical Traction. 4. Evaluate the use of Power Electronic Technologies in various process controls. 5. Understand different lighting scheme and create lighting system using LED Technologies. 6. Select a drive for a particular application based on power rating. 7. Select a drive based on mechanical characteristics for a particular drive application 8. Operate and maintain solid state drives for speed control of DC and AC machines 9. Operate and maintain solid state drives for speed control of various special electrical machines. 10. Understand Heating, Welding methods and apply it 11. Understand Eectrolytic process in brief. 2

3 [2]Course Contents: Sr. No. Content 1. Electric Drives: Advantages of electric drives, Characteristics of different mechanical loads, Types of motors used in electric drive, Electric braking, Plugging, Rheostat braking, Regenerative braking, Methods of power transfer by direct coupling by using devices like belt drive, gears, pulley drives etc. Examples of selection of motors for different types of domestic loads Selection of drive for applications such as general workshop, textile mill, paper mill, steel mill, printing press, crane, lift etc. Application of flywheel. Specifications of commonly used motors e.g. squirrel cage, slip ring induction motors, AC series motors, FKW motor 2. Illumination: Nature of light, visibility spectrum curve of relative sensitivity of human eye and wave length of light, Different type of lamps, construction and working of incandescent and discharge lamps their characteristics, fittings required for filament lamp, mercury vapour lamp, fluorescent lamp, metal halide lamp, neon lamp General ideas bout street lighting, flood lighting, monument lighting and decorative lighting, light characteristics etc.,led Lighting 3. Electric Heating: Advantages of electrical heating, Heating methods Resistance heating direct and indirect resistance heating, electric ovens, their temperature range, properties of resistance heating elements, domestic water heaters and other heating appliances and thermostat control circuit Induction heating; principle of core type and coreless induction furnace Electric arc heating, direct and indirect arc heating, construction, working and applications of arc furnace Dielectric heating, applications in various industrial fields Infra-red heating and its applications Microwave heating, Simple design problems of resistance heating element 4. Electric Welding: Advantages of electric welding Welding methods, Principles of resistance welding, types spot, projection seam and butt, welding and welding equipment used Principle of arc production, electric arc welding, characteristics of arc, carbon arc, metal arc, hydrogen arc welding and their applications Power supply required Advantages of using coated electrodes, comparison between AC and DC arc welding, welding control circuits, welding of aluminium and copper, Introduction to TIG, MIG welding Teaching Hours % Weig ht age

4 5. Electrolytic Processes: Need of electro-deposition, Laws of electrolysis, process of electrodeposition - clearing, operation, deposition of metals, polishing, buffing Equipment and accessories for electroplating, Factors affecting electrodeposition Principle of galvanizing and its applications, Principle of anodising and its applications Electroplating on non-conducting materials Manufacture of chemicals by electrolytic process and electrolysis process 6. Electrical Circuits used in Refrigeration, Air Conditioning and Water Coolers: Principle of air conditioning, vapour pressure, refrigeration cycle, ecofriendly refrigerants Description of Electrical circuit used in refrigerator, air conditioner and water cooler 7. Electric Traction: Electric traction, Advantages of electric traction Different systems of electric traction, DC and AC systems, diesel electric system, types of services urban, sub-urban, and main lines and their speed-time curves Different accessories for track electrification such as overhead capacitor wire, conductor rail system, current collector-pantograph Factors affecting scheduled speed Electrical block diagram of an electric locomotive with description of various equipment and accessories, Types of motors used for electric traction, Starting and braking of traction motors Introduction to EMU and metro railways [3 List of Reference Books: 1. Generation and Utilization of Electrical Energy by S. Sivanagaruju, Pearson 2. Art and Science of Utilization of Electrical Energy by H.Partap, Dhanpat Rai & Sons 3. Utilization of Electrical Energy by J. B. Gupta, Kataria Publications 4. A Text Book of Electrical Power by Dr. S. L. Uppal, Khanna Publications 5. Modern Electric Traction by H.Partap, Dhanpat Rai & Sons 6. Utilization of Electrical Energy by O. S. Taylor, Pitman Publications 7. Generation, Distribution and Utilization if Electrical Power by C. L.Wadhwa, Wiley Eastern 4

5 [4]List of Open source software and learning websites required for experiments: ehtla.pdf 3. ftp://ftp.elet.polimi.it/users/massimo.ghioni/power%20electronics%20/mot or%20control/motor%20control%20overview/introduction%20to%2 0ELECTRICAL%20DRIVES.pdf 4. /Lesson-05/pdf/L-5(NKK)(IE)%20((EE)NPTEL).pdf Electrolysis+and+Its+Uses.pdf Refrigeration%20and%20air%20conditioning.pdf A%20review%20of%20Active%20Power%20Filter.pdf

6 [5]Learning Assignments: 1. Electric Drives: Advantages of electric drives, Characteristics of different mechanical loads, Types of motors used in electric drive, Electric braking, Plugging, Rheostat braking, Regenerative braking, Methods of power transfer by direct coupling by using devices like belt drive, gears, pulley drives etc. Examples of selection of motors for different types of domestic loads Selection of drive for applications such as general workshop, textile mill, paper mill, steel mill, printing press, crane, lift etc. Application of flywheel. Specifications of commonly used motors e.g. squirrel cage, slip ring induction motors, AC series motors, FKW motor ATTEMPT ANY FIVE: SR NO. QUESTION YEAR MARKS 1 Why electrical drive is preferred over mechanical drive? Discuss the factors governing selection of an electric motor for a particular service A motor fitted with a flywheel supplies a load of torque 1000 N-m for 2 seconds. During no-load period the flywheel regains its original speed. The motor torque is required to be limited to 500 N-m. Determine the moment of inertia of flywheel. The no-load speed of the motor is 500 RPM and its full load slip is 10% Explain regenerative braking of DC motor. OR State the types of electric braking. Explain any one in detail. Suggest suitable A.C. and D.C. drives for following applications. Give reasons for the same. 1. Pump 2. Blower 3. Hoist 4. Excavator 5 Classify electric drives and state the factors affecting selection of drive. DEC-10 OCT-16 DEC-10 DEC-11 DEC-15 DEC-11 JUN-12 6 Explain how will you apply plugging, rheostatic and regenerative braking to an induction motor 7 Justify the following statement with explanation (i)d C series motors never start without load DEC-13 (ii) D C series motors are used where huge starting torque is required 8 Compare slip ring induction motor with squirrel cage induction motor. Why double cage induction motor is used? A 250volt D.C.shunt motor has armature resistance of 0.25 ohm, on load it 9 takes an armature current of 50Amp and runs at 750r.p.m. If the flux of motor is reduced by 10% without changing the load torque, find the new speed of the motor 10 Explain electric drives and its classification in detail. DEC Discuss rheostatic braking applied to DC motor with neat sketch 12 State the methods of speed control of 3- induction motor and explain any one method in detail. 6

7 13 Explain four quadrant operation of a drive with suitable diagrams. 14 Explain Ward-Leonard system of speed control with diagram. Also state the advantages & disadvantages of this method. 15 Explain the method of series-parallel starting of DC series motors. What are its advantages? OCT State the methods of speed control of three phase induction motor and explain any two methods. OCT Enlist different types of electric braking. Explain in brief along with an application the regenerative braking of induction motor. OCT Explain running characteristics of three phase induction motor. OCT-16 7

8 2. Illumination: Nature of light, visibility spectrum curve of relative sensitivity of human eye and wave length of light, Different type of lamps, construction and working of incandescent and discharge lamps their characteristics, fittings required for filament lamp, mercury vapour lamp, fluorescent lamp, metal halide lamp, neon lamp General ideas bout street lighting, flood lighting, monument lighting and decorative lighting, light characteristics etc.,led Lighting ATTMEPT ANY FIVE: SR NO. 1 Define the terms: (1) Luminous intensity (2) Luminous efficiency (3) Utilization factor, (4) Reduction factor, (5) Reflection factor, (6) candle power,(7) Glare 2 State and explain laws of illumination. 3 QUESTION YEAR MARKS The illumination of drawing office 30 m 10 m is to have a value of 250 lux and is to be provided by number of 300 watt filament lamps. If the utilization factor is 0.4 and depreciation factor is 0.9, determine the number of lamps required. The efficiency of each lamp is 14 lumens per watt. DEC-10 MAY-15 DEC-10 JUNE DEC State and explain laws of illumination. JUN Explain the working of fluorescent tube with the help of circuit Diagram 6 Discuss various factors to be considered while designing any lighting scheme. JUN JUN-11 7 State and explain square law of illumination. DEC-11 8 Explain fluorescent lamp with diagram. DEC-11 9 Explain street lighting. DEC State and explain square laws of illumination. 11 Explain the principle of operation& working of a sodium vapor lamp giving its neat sketch. JUN-12 JUN-12 DEC-15 Explain factory lighting. JUN OR DEC-15 Explain the design procedure of heating element. 13 Explain briefly how you will design lighting scheme. JUN

9 14 Explain street lighting. 15 Explain the working of fluorescent tube with the help of circuit Diagram 17 Discuss various factors to be considered while designing any lighting scheme 18 Explain the principle of operation of HPMV (High pressure mercury vapour ) lamp giving its neat sketch. DEC-13 DEC-13 MAY-15 DEC-13 DEC What is flood lighting? Where is it used? MAY A workshop 30m*15m is to have an illumination of 150 lux on its working place; the lamps are hung 5m above it. Give the layout of a suitable installation using 80 watt fluorescent lamp. Assume suitable data. MAY Explain different ways of current collection in Electric traction. Oct Define the following terms with its range w.r. to illumination. (a) Co-efficient of utilization, (b) Depreciation factor, (c) Waste light factor, (d) Space-height ratio Oct-16 9

10 3. Electric Heating: Advantages of electrical heating, Heating methods Resistance heating direct and indirect resistance heating, electric ovens, their temperature range, properties of resistance heating elements, domestic water heaters and other heating appliances and thermostat control circuit Induction heating; principle of core type and coreless induction furnace Electric arc heating, direct and indirect arc heating, construction, workingand applications of arc furnace Dielectric heating, applications in various industrial fields Infra-red heating and its applications Microwave heating, Simple design problems of resistance heating element ATTEMPT ANY SIX: SR NO. QUESTION YEAR MARKS 1 State and explain advantages of electrically produced heat. What are the essential properties of resistance heating elements? 2 Explain with diagram vertical core type induction furnace 3 Explain eddy current heating and its application. 4 Explain dielectric heating.state applications of dielectric heating. A 15KW 220V single phase resistance oven employs nickel chrome wire for its heating elements. If the wire temperature is not to exceed 1000o C and 5 the temperature of the charge is to be600 o C. Calculate the diameter and length of wire. Assume radiating efficiency as 0.6 and emissivity as 0.9 and specific resistance of nickel chrome alloy as Ω m. 6 Explain direct and indirect heating using arc furnace. Give Equivalent circuit of arc furnace. DEC-10 DEC-10 DEC-10 DEC-13 JUN-11 OCT-16 JUN-11 JUN-11 7 Explain design procedure of heating element with necessary expressions. DEC-11 A 30 KW, 400 volts resistance oven is to employ nickel chrome strip mm thick for 3 delta connected heating elements. If wire temperature is 1100⁰ C and that of charge is 700⁰ C. Estimate suitable width for the strip. Assume emissivity (є ) = 0.9, radiating efficiency ( η ) = 0.5 DEC-11 9 Explain principle and working of an indirect core type furnace. DEC Explain design procedure of heating element JUN-12 10

11 DEC-15 A 30 KW, 400 volts resistance oven is to employ nickel chrome strip mm thick for 3 star connected heating elements. If wire temperature is 1100⁰C and that of charge is 700⁰ C. Estimate suitable width for the strip. Assume emissivity (є ) = 0.9, radiating efficiency (η) = 0.5 JUN Explain principle and working of a vertical core type furnace. JUN State and explain advantages of electrically produced heat. Explain methods of transfer of heat. 14 Explain with diagram direct core type and coreless type induction furnace. 15 Dielectric heating is to be employed to heat a slab of insulating material 20 mm thick and 1500 mm 2 in area. Power required is 200 watts and frequency of 3 MHz is to be used. The material has a permittivity of 5 and a power factor of Determine the voltage necessary and the current which will flow through the material. 16 Explain dielectric heating.state applications of dielectric heating. DEC Define electric heating and also explain induction heating. DEC Explain principle and working of a vertical core type furnace. DEC What are the advantages of electric heating? Give classification ofelectric MAY-15 heating. 20 With a neat diagram, explain Ajax-Wyatt furnace. State advantages of it. MAY Explain induction heating and direct core type induction furnace. DEC Estimate the efficiency of a high frequency induction furnace which takes 10 minutes to melt 1.8 kg of aluminum. The input to the furnace being 5 kw and initial temperature is 15 0 C. Given : specific heat of aluminum = 880 J/Kg/ 0 C Melting point of aluminum = C Latent heat of fusion of aluminum = 32 KJ/Kg 1 J = 2.78 X 10-7 kwh 23 State different methods of electrical heating and explain resistance heating. 24 State different methods of electrical heating and explain resistance heating. DEC-15 Oct-16 OCT-16 11

12 4. Electric Welding: Advantages of electric welding Welding methods, Principles of resistance welding, types spot, projection seam and butt, welding and welding equipment used Principle of arc production, electric arc welding, characteristics of arc,carbon arc, metal arc, hydrogen arc welding and their applications Power supply required Advantages of using coatedelectrodes, comparison between AC and DC arc welding, welding controlcircuits, welding of aluminium and copper, Introduction to TIG, MIG welding ATTEMPT ANY TWO: SR NO. QUESTION YEAR MARKS 1 Describe with help of neat sketches various types of resistance welding in detail. 2 Describe with help of neat sketches various types of electric arc welding in detail. 3 Explain different types of resistance welding. 4 Name and explain various types of welding methods. DEC-10 JUN-11 DEC-11 DEC-15 MAY-15 DEC-15 5 Discuss advantages of electric welding and give classification of electric welding. 6 Discuss the process of electric arc welding. 7 Compare resistance welding and arc welding. OCT-16 12

13 5. Electrolytic Process: Principle, Faradays laws of electrolysis, Current efficiency, Energy efficiency etc., Rating of metals, Production of chemicals, Electro-deposition, Electroplating, Power supply for electrolytic processes ATTEMPT ANY THREE: SR.NO. QUESTION YEAR MARKS 1 Explain the terms used in electrolytic process (i) Current efficiency DEC (ii) Energy efficiency 2 State and explain Faraday s laws of electrolysis. DEC Explain electro-deposition processes and discuss various factors DEC governing the electro deposition processes. 4 State and explain Faraday s Law of electrolysis. JUN What is electroplating.explain process of electro plating. JUN-11 MAY-15 6 Explain electro-deposition process. JUN Explain power supply for electrolysis processes. 8 State Faraday s laws of electrolysis. Explain power supply for electrolytic processes. 9 Explain basic principle of electrolysis and explain Faraday s laws of electrolysis. DEC-11 JUN-12 DEC-15 OCT-16 DEC

14 6. Electrical Circuits used in Refrigeration, Air Conditioning and Water Coolers: Principle of air conditioning, vapour pressure, refrigeration cycle, eco-friendly refrigerants Description of Electrical circuit used in refrigerator, air conditioner and water cooler ATTEMPT ALL SR.NO. QUESTION YEAR MARKS 1 Explain principle of air conditioning OCT-16 14

15 7. Electric Traction: Electric traction, Advantages of electric traction Different systems of electric traction, DC and AC systems, diesel electric system, types of services urban, sub-urban, and main lines and their speed-time curves Different accessories for track electrification such as overhead capacitor wire, conductor rail system, current collector-pantograph Factors affecting scheduled speed Electrical block diagram of an electric locomotive with description of various equipment and accessories, Types of motors used for electric traction, Starting and braking of traction motors Introduction to EMU and metro railways ATTEMPT ANY EIGHT: SR NO. QUESTION YEAR MARKS 1 State the main requirements for an ideal traction system. Give merits and demerits of electric traction over steam engine traction. Using the simplified trapezoidal speed time curve, derive an expression for 2 the maximum speed in kmph in terms of acceleration, retardation, distance between stops and actual time of run between stops. A train is required to run between two stations 1.6 km apart at an average speed of 40 kmph. The run is to make to simplified quadrilateral speed-time 3 curve. If the maximum speed is to be limited to 64 kmph, acceleration to 2 kmphps and coasting and braking retardations to 0.16 kmphps and 3.2 kmphps respectively, determine the duration of acceleration, coasting and braking. Deduce the expression for : 4 (i) The tractive effort transferred to the driving wheel in terms of wheel diameter, motor torque, gear ratio and efficiency of transmission. (ii) The tractive effort for propulsion of train up and down the gradient. An electric train weighing 200 tonne has eight motors geared to driving wheel; each wheel is of 90 cm in diameter. Determine the torque developed 5 by each motor to accelerate the train to a speed of 48 kmph in 30 seconds up a gradient of 1 in 200. The tractive resistance is of 5 newtons per tonne, the effect of rotationalinertia is 10% of train weight, the gear ratio is 4 to 1 and gearing efficiency is 80%. Draw the speed time curves of electric train for 6 (i)city Service(ii)Suburban service (iii)main line service and explain their characteristics. 7 Define average speed,crest speed and schedule speed and discuss the factors which affect schedule speed of a train 8 9 An electric train has a schedule speed of 25 kmph between two stations 800 meters apart. The duration of station stop is 20sec,the maximum speed is 20% higher than the average running speed and breaking retardation is 3 Kmphps. Calculate the rate of acceleration required to operate this service. Assume trapezoidal speed-time curve. Drive on expression for specific energy output and specific energy consumption using a simplified speed-time curve and discuss the factors affecting specific energy consumption. DEC-10 DEC-10 DEC-15 DEC-10 DEC-10 DEC-10 JUN-11 JUN-11 JUN-11 JUN-11 15

16 10 A 500-tonne goods train is to be hauled by a locomotive up gradient of 1 in 40 with an acceleration of 1.5 kmphps. Determine the weight of the locomotive and number of axles if the axle load isnot to exceed 24 tonnes. JUN-11 Co-efficient of adhesion is 0.31 and track resistance is 45 N/tone.Allow 10% for rotational inertia. 11 Explain clearly speed time curves for urban and sub-urban services. DEC A train runs with an average speed of 40 kmph. Distance between stations is 2 km, values of acceleration and retardation are 1.5 kmph and 2.5 kmph DEC-11 respectively. Find the maximum speed of train assuming trapezoidal speed JUN-12 time curve. 13 Explain braking of traction motors in brief. DEC Explain regenerative breaking used in traction system. 15 Discuss relative advantages and disadvantages of steam, diesel electric and electric systems of traction. 16 Explain the terms dead weight, accelerating weight and adhesive weight in a locomotive. Explain the factors affecting specific energy consumption. 17 A 400 tonne goods train is to be hauled by a locomotive up a gradient of 2 % with acceleration of 1 kmphps. Coefficient of adhesion is 20 %; track resistance is 40 N/tonne and effective rotating masses 10 % of the dead weight. Find the weight of locomotive and number of axles, if the axle load is not to be increased beyond 19 tonnes. 18 Explain briefly different systems of railway track electrification. JUN Explain series-parallel control of traction motors having two motors and hence find out overall starting efficiency. 20 Define traction, Explain the terms dead weight, accelerating weight and adhesive weight in a locomotive. Explain the factors affecting specific energy Consumption. DEC -13 A train has schedule speed of 60 km / hour between the stop which are 6 km 21 apart. Determine the crest speed over the run, assuming trapezoidal speedtime curve. The train accelerates at 2 kmphps and retards at 3 kmphps. Duration of stop is 60 seconds DEC An electric train has quadrilateral speed-time curve as follows: i. Uniform acceleration from rest at 2 kmphps for 30 seconds ii.coasting for 50 seconds 22 iii.breaking period of 20 seconds. The train is moving a uniform up gradient of 1%, tractive resistance is 40 newton per tonne, rotational inertia effect 10% of dead weight, duration of station stop 15 seconds and overall efficiency of transmission gear and motor as 75%. Calculate the value of its schedule speed and specific energy consumption of run. An electric train is to have acceleration and braking retardation of 0.8 km/h/s 23 and 3.2km/h/s respectively. If time for stops 26 sec. and ratio of maximum to average speed is 1.3, find schedule speed for a run of 1.5 km. Assume trapezoidal speed-timecurve. 24 Draw a diagram of AC electric locomotive and explain function of each part in it. MAY An 8 pole, 50 Hz,3 phase cage induction motor equipped with a flywheel is MAY-15 16

17 driving a mill, which requires a load torque of 1400 kg-m during the rolling operation lasting 10 seconds. The torque then drops to 200 Kg-m for 30 seconds, the cycle being repeated. The motor is capable delivering a maximum torque of 1050 Kg-m running at a slip of10%. The moment of inertia of moving parts is 50,000 Kgm 2. Determine the speed of the motor after 5 seconds during the rolling operation. 26 What is co-efficient of adhesion? What are the factors affecting the co-efficient of adhesion? MAY-15 An electric train accelerates uniformly from rest to a speed of 50 km-ph in seconds. If then coasts for1 minute 10 seconds against a constant resistance of 70 N per tonne and is braked to rest at 4 kmphps in 10 seconds. Calculate the MAY-15 schedule speed, if the station stops are of 15 second duration. 28 State various types of current collectors in common use for over head contact system. Describe with a neat diagram the pantograph collector. MAY-15 A train weighing 500 tonnes is going a gradient of 20 in It is desired 29 to maintain train speed at 40kmph by regenerative braking. Calculate the power fed into the line. A tractive resistance is 40 N per tonne and allows rotational inertia of 10% and efficiency of conversion of 75 %. MAY-15 An electric train weighing 200 tonnes has 8 motors geared to driving wheels; each 30 wheel is 90 cm diameters. Determine the torque developed by each motor to accelerate the train to a speed of 48 kmph in 30 seconds up a gradient of 1 in 200. DEC-15 The tractive resistance is of 50 N/Tonne, the effect of rotational inertia is 10% of the train weight, the gear ratio is 4 to 1 and gearing efficiency is 80 % 31 Explain the chief requirement of electric motors used for traction work. DEC Explain the tractive effort for propulsion of train. DEC Compare AC and DC traction system 34 Explain following term (1) co-efficient of adhesion (2) schedule speed (3) specific energy consumption. 35 What do you understand by Tractive efforts? Derive the expression for the same OCT Draw and explain typical speed time curve for electric traction. Explain what do you understand by Crest speed, Average speed and OCT-16 Scheduled speed 37 A 500 tonnes goods train is to be hauled by a locomotive up a gradient of 1 in 40 with acceleration of 1.5 kmphps. Determine the weight of locomotive and number of axles, if axle load should not exceed 24 OCT-16 tonnes. Coefficient of adhesion is 0.31, track resistance is 45 N/ton and effective rotational mass is 10% of dead weight 38 Explain different ways of current collection in Electric traction. OCT-16 17