Tuesday 31 July 2018

Regarding DTE hackathon

Dear Students,

Education Ministry, Govt. of Gujarat has initiated series of interventions to harness creative potential of 14 lacs students across 60 plus universities and extending all possible support for their innovations and start-ups. Students are capable to become the country’s largest force of problem solvers and eventually become job creators. To orient students towards problem-solving, the Education Department had organized "Smart Gujarat for New India Hackathon 2017-18". Recently, Summer Innovation Challenge 2018 (SIC 2018) on the theme of “WATER” has been launched by Education Department.

Along the lines of these interventions, the Directorate of Technical Education (DTE), Government of Gujarat has announced “DTE Hackathon”. As a part of this initiative, altogether 20 problem statements have been identified within DTE. It is desirable that students and faculties together    participate in  the team and across the state, they are encouraged to register themselves and submit their Proof-of-Concept (PoC) or potential solution for the listed problems, on the given link https://sites.google.com/view/ dtehackathon2018  before 6th August 2018. Students working on the challenges may have to present the PoC or prototype on the event day.

The student and faculty teams, who are bringing the best ideas/solutions for the listed problems will be encouraged with awards.

You are requested to widely publicise the details of "DTE Hackathon" amongst the students and encourage them for participation.

if you have any query, please mail us at ssipgujarat@gmail.com with Subject line DTE Hackathon Query

Students are requested to participate and if any query meet Prof. D R Dobariya/ Prof. A M Shah

Mid Semester Exam Date


Monday 30 July 2018

Industrial visit at Tushar Trans.Equipment Ltd, Bharuch on 2/8/18


Industrial visit is arranged as per following schedule for 7th sem/5th sem students at Tushar Trans.Equipment Ltd, Bharuch on 2/8/18(BATCH-A/B for 7th and 5th sem both) 
Interested students shall register before 31/7/18 without fail. Once register, students must attend the same. Preference will be given to 7th sem students in case of more registrations.

Date : 02/08/2018
 
Time : 10:30 AM to 12:00 AM ( First Bench )
           1:00 PM to 2:30 ( Second Bench )


CLICK HERE TO REGISTER

REGISTRATION FORM FOR PLACEMENT DETAILS (FOR CURRENT 2018 FINAL YEAR ELECTRICAL BATCH ONLY)


All the final year students are here by inform to get register and enter their placement details on or before 2/8/18 without fail. Please take utmost care while filling the details. All the details must be 100% authentic and correct.


CLICK HERE


Prof. P.K.Shah

List of students and schedule for Mega Switchgears Ltd Visit


Registered students shall come as per following schedule at below mentioned address.

Address54/3B, GIDC Industrial Estate,Makarpura Industrial Estate, Makarpura GIDC, Makarpura, Vadodara, Gujarat 390010
Time: 10.00 A.M at company premises at Makarpura,Vadodara.

Direction: Students can reach at susen circle first and then reach at above mentioned address.

LIST OF STUDENTS FOR VISIT ON 31/7/18
Enrollment No Name Semester Contact No
160143109025 VASAVA HIMATBHAI VASANTBHAI sem 7 8980898285
150140109077 RAMDEV PARMAR sem 7 7567590756
150140109099 PRAJAPATI JAYDEEP sem 7 7622028680
150140109093 Patel snehal sem 7 9727238375
150140109079 Patel Aaqib Iqbalhusein Valibhai sem 7 7226951389
150140109030 GANVIT MINESH DEVLUBHAI sem 7 9714419581
150140109018 CHAUDHARI KRUNAL sem 7 7203006364
150140109002 Ahir dhaval  sem 7 7046328456
150140109115 Tandel bhavin  sem 7 7046194498
150140109111 Solanki Hitendra sem 7 9714398256
150140109020 JITESH CHAWDA sem 7 9601880716
150140109076 Parmar Charandasi N sem 7 8866751094
160143109019 S VINAYRAO S KRISHNARAO sem 7 7405658813
160143109015 Rajput Neel dilipbhai sem 7 8469847449
160143109001 Bhamre arpita k sem 7 7285044328
160143109023 Upadhyay Nimesh pradipbhai sem 7 8980177875
160143109005 Jani brijesh k sem 7 7016204713
160143109026 Yadav Keshav shyamnarayan sem 7 8866860891
160143109022 Solanki krishnaben R sem 7 9924298930
160143109022 Solanki Krishna rajubhai sem 7 9924298930
150140109019 CHAUDHARI YASHKUMAR RAJESHBHAI sem 7 8141201435
150140109108 Aman Sharma sem 7 9925434217
150140109101 VIRAL PRAJAPATI sem 7 8460277120
150140109081 ARCHIT C PATEL sem 7 8401477010
150140109043 Kalshariya Rakesh Chhaganbhai sem 7 9909805890
150140109080 PATEL AKASHKUMAR VANMALIBHAI sem 7 9979088094
150140109110 Snehi Rahul G. sem 7 7698192589
150140109123 VASAVA TEJASKUMAR ARVINDBHAI sem 7 7621073357
150140109062 Makwana Priyeshkumar Maheshbhai sem 7 9033210610
150140109042 Kacha Paras P. sem 7 9033528582
150140109042 Kacha Paras sem 7 9033528582
150140109113 Prem Sukhadwala sem 7 9825515697
150140109107 Roshan sahu  sem 7 9824374389
150140109053 Ladani Divyesh Rajanibhai sem 7 9512130221
150140109089 PATEL MAHAMMADFAIZAN S. sem 7 8200682553
150140109009 Divya Bavaskar sem 7 7383126759
150140109126 Yadav Rahul Lalbahadur sem 7 9974597324
150140109125 Patel Vishwa Hitendrakumar sem 7 9426145746
150140109040 Jadav Parth Arjunbhai sem 7 9033111021
150140109082 Patel Arpit Jitendrabhai sem 7 7202847639
150140109072 PAMU VISHAL NARSINHBHAI  sem 7 7359791406
150150109097 PATEL ZAID SAEED  sem 7 9998381895
150140109109 Richa Shukla sem 7 9409347521
170143109031 Rana Ashish Dasharathbhai sem 5 7600735449
170143109024 PATEL KHUSHBU NAVINKUMAR sem 5 9265400846
160140109053 Pancholi Shivam mukeshkumar sem 5 8128225321
16014010947 MOJIDRA JAYDEEPKUMAR MUKESHBHAI sem 5 8530149526
160140109051 PANCHAL NIKET sem 5 9909690701
160140109038 MALANI BHAUMIK JITESHBHAI sem 5 9429014373

LIST OF STUDENTS FOR VISIT ON 01/8/18
150140109095 Yash Patel sem 7 9409263609
150140109045 Aakash Kanojiya sem 7 8735014424
150140109046 Sahil kantharia sem 7 7359375505
150140109041 Jahnavi Tadvi sem 7 9522733151
160143109009 MAHIDA MAHENDRASINH PRAVINSINH sem 7 9998496387
160143109006 Drumil jani sem 7 9429270046
140140109120 Rudra vasava sem 7 8200684215
150140109034 HALPATI PURVESHKUMAR CHHIBHUBHAI sem 7 9638123884
150140109022 Chothani dhruvikkuamar jitubhai sem 7 7359495282
150140109105 Rathod parth sem 7 9157381004
150140109013 BHATTI PARTH sem 7 8530252885
150140109001 ADROJA KISHANKUMAR sem 7 8347115889
150140109044 KANKOTIYA JAYTUN sem 7 8347778312
150140109022 CHOTHANI DHRUVIK sem 7 7369495282
150140109068 Mishra Ankur sem 7 8238192258
160143109018 RATHVA PARTH SHANKARBHAI sem 7 9687438760
150140109023 Sandeep dhola sem 7 9067720923
150140109085 Patel Harsh Rohitbhai sem 7 7567428083
15014010904 Patel Tejash Jayantilal sem 7 9099865782
160140109037 Makwana Rahul Sureshbhai sem 5 8980216181
160140109024 GAMIT GAURAVKUMAR ARVINDBHAI sem 5 9737869069
160140109115 VEGAD CHINTANSINH sem 5 9512384870
170143109019 Parmar Nisha Arunbhai sem 5 7698722602
160140109110 VANIYA DARSHANKUMAR B sem 5 9714663604
160140109073 Priyansh Patel sem 5 9687131025
160140109008 Nihar  R. Barot sem 5 8460271433
160140109030 Karena Chetan keshubhai sem 5 8469785691
160140109084 RAJPUT JIGARSINH M sem 5 9722851469
170143109034 MOIZUDDIN NIZAMUDDIN SAIYED sem 5 8000854247
160140109069 PATEL MIT R. sem 5 7096358893
160140109086 RATHVA BRIJESHKUMAR sem 5 8849437425
160140109074 PATEL VATSAL NAVINBHAI sem 5 8347901406
160140109082 RABADIYA  VIMAL JAGDISHBHAI sem 5 9913276538
170143109035 shaikh naushir m sem 5 8488812991
160140109013 Chaudhari Hetasvi Anilbhai sem 5 7567011730
160140109041 Mohammed Fahad Misarwala sem 5 8511474050
160140109093 SHAH PIYUSH J. sem 5 9033835261
160140109032 Kazi Faizanulhasan .M sem 5 9662066289
160140109078 Dhruvil Prajapati sem 5 70415 56277
160140109040 Maulik Mathukiya sem 5 7069452792
160140109033 Krunal Kyada sem 5 9662983982
160140109021 Rajan Dobariya sem 5 7600951364
160140109106 Upadhyay Ashish krishandatt sem 5 7284906785
160140109001 Sheba Cherian sem 5 7284906785
160140109102 Tandel Prem sem 5 7284906785
170143109037 Dhruti Soni sem 5 7284906785


Wednesday 25 July 2018

Industrial Visit at Mega Swithgears Ltd,Vadodara(For 7th sem and 5th sem)


Industrial visit is arranged as per following schedule for 7th sem/5th sem students at MEGA SWITCHGEARS LTD, Makarpura,Vadodara on 31/7/18(BATCH-A for 7th and 5th sem both) and 1/8/18 ((BATCH-B for 7th and 5th sem both).

Interested students shall register before 27/7/18 without fail. Once register, students must attend the same. Preference will be given to 7th sem students in case of more registrations.


Register Here

Friday 20 July 2018


3rd  SEMESTER ELECTRICAL
DC Machines & Transformer (2130904)
D.C. Machine
Assignment – I
 1)A 4- pole, d.c. shunt generator with a wave wound  armature having 390 conductors has to supply the load of 500 lamps, each of 100W at 250 V. Allow  10V as voltage drop in the connecting leads of the wire between generator and a brush contact drop of 1 volt/brush. Calculate the speed of armature at which the generator should be in driven. The flux/pole is 30mwb.The armature and shunt field resistances are 0.05Ω and 65 Ω respectively. (Ans : 698rpm) .
 2)A shunt generator deliver 195A at 250V, armature and shunt field resistances are 0.02 Ω and 50 Ω respectively. The iron and friction losses are 950W.Calculate (1) Emf generated ,(2)Total copper loss,(3)Output of prime-mover,(4)Mechanical efficiency , electrical efficiency and total efficiency.(Ans :254V,2050W,50800W, 98%,95.9%,94.2%).
3) A shunt generator has a full load current of 196A at 220V. Stray losses are 720W and the shunt field resistance is 55 Ω. It has a full  load efficiency of 88%. Find the armature resistance. Also find the load current at maximum efficiency.(Ans : 0.114 Ω , 122.28A).
4) A 4-pole DC shunt generator with a shunt & armature resistances of 100 Ω & 1 Ω respectively .It has 378 wave connected conductors in its armature. The flux/pole is 20mwb.If a load resistance of 10 Ω is connected across armature terminals  the generator is driven at 1000rpm. Calculate the power absorbs by the load and terminal voltage. (Ans : 5153.5W,227V).
 5)In a DC machine the total iron loss is 8KW at its rated speed & excitation .If  excitation remains same but speed is reduced by 25% the  total Iron loss is found to be 5KW. Calculate the hysteresis & eddy current losses. (Ans : 2666.67W,5333.33W).
 6)Two shunt generators with armature resistance 0.1 Ω and field resistance of 20 Ω connected in parallel & supply load current is 4000A. Generated emf of both are 210V and 220V respectively. Calculate the busbar voltage and output of each machine.(Ans : 14.93V,29.112kW,30.605kW).
 7)Two DC shunt generator connected in parallel to supply at load of 1500A. One generator feed armature resistance of 0.5 Ω, emf of  400V. And other generator feed armature resistance of 0.04 Ω and emf of 440V. And field resistances are 100 Ω and 80 Ω respectively. Calculate the load supply by the generator and busbar voltage .(Ans : 12.88kW,558.9kW,381.2A).
8)A 200V 4-pole lap wound DC shunt motor has 800 conductors of its armature winding. The armature and field winding resistances are 0.5 Ω and 200 Ω respectively. Motor takes 21A and flux /pole is 30mwb. Find the torque and speed of the motor .(Ans : 475rpm , 76.4 Nm).
  9)A  230V DC shunt motor runs at a 1000rpm and takes 5A.The armature and    shunt field resistances are 0.25Ω and 230 Ω respectively. Determine the drop in speed when the motor is loaded  & takes 41A from the mains.(Ans : 39.31rpm).
  10)A DC shunt motor takes an armature current of 120A from 400V supply  & runs at 800rpm. Calculate armature current and motor speed when the magnetic field is reduced to 80% of its initial value. The armature resistance is 0.25 Ω and the torque remains same in both case.(Ans : 150A,979.72rpm).
   11)A 250V DC shunt motor takes rated current of 67A. Armature and field  resistances are 0.15 Ω and 166.67 Ω respectively. The motor takes 6.5A when running without load at 1280rpm. Determine  (1) Full load speed of motor ,(2)Speed regulation ,(3) speed when the motor current is 50A,(4)Speed when motor current is 40A and there is a armature reaction of 3%.(Ans : 1233.40rpm,0.037,1246.5rpm,1216.59rpm).
    12) A 500V DC shunt motor runs at its nominal speed of 250rpm, the armature current 200A.Calculate the speed when a resistance is inserted in the field winding to reduce  shunt  field to 80% of normal value. And the armature current is 100A ,take armature resistance is 0.12 Ω.(Ans : 320.73rpm).
   13)A 250V DC shunt motor  has an armature resistance of 0.5 Ω and field resistance of 250 Ω. When driving  a load of constant torque at 600rpm ,the armature current is 20A.If it is desire to raise the speed from 600rpm to 800rpm ,what resistance should be inserted in the field circuit.(Ans : 5911.68 Ω). 
  14)A DC shunt motor drive a centrifugal pump whose torque varies as the squre of the speed. Motor is feed from 200V DC supply and takes 50A, when running at 1000rpm .What resistance must be inserted in the armature circuit to reduce the speed to 800rpm. Take armature and field resistances 0.1Ω and 100 Ω respectively.(Ans : 1.329 Ω).
15)A DC series motor with un-saturated speed and negligible armature and series resistances when running at a certain speed on a given load takes 15A at 460V.If the load torque  vary as the cube of the speed ,calculate the resistance required to reduce the speed by 25%.(Ans : 7.26 Ω). 
 16)A 4-pole,110V ,wave wound dc series generator has armature and series field resistances of 0.5Ω and 0.3 Ω respectively. Calculate the induced emf when the generator delivers load current of 10A at 110V. Calculate the speed at which it should be driven if flux per pole is 5mwb and armature conductors are 1200.(Ans : 118V,590rpm).
 17)A 2-pole long shunt compound generator has shunt field ,series field and armature resistances of 200 Ω,0.5 Ω and 0.3 Ω respectively. Calculate the induced emf if the generator delivers load of 4kW at 400V.Allow a total brush drop of 2V.(Ans : 411.6V).
 18) A 10kW DC shunt generator has the following losses at full load 1)mechanical loss=290W,2)Iron loss=410W,3)Shunt cu loss=120W,4)Armature cu loss=595W.Calculate efficiency at 1)full load ,2)at 25% of full load.(Ans : 87.6%,74.47%).
 19)A 4-pole DC machine has a lap wound armature with 90 slots each                  containing 6 conductors. If the machine runs at 1500rpm and the flux per pole is 0.03wb. Calculate the emf generated. If the machine runs as shunt generator with same field flux .The armature and field resistances being 1 Ω and 200 Ω respectively. Calculate output current when the armature current is 25A. If due to a fall in speed, emf becames  380V. Calculate load current in a 40 Ω load.(Ans  : 405V,23.1A,9.2A).
 20) The open circuit characteristic of a d.c. shunt generator at 300rpm is
Ish (A)
    0
   0.2
   0.3
  0.4 
  0.5 
   0.6  
    0.7
E0 (V)
   7.5
   93
  135
 165
 186
  202
   215
   The field resistance is adjusted to 354.5 Ω and speed is 300rpm. Determine 1) residual flux graphically the no load voltage, 2)critical field  resistance , 3) critical speed for the given field resistance, 4) Additional resistance inserted in the field resistance to reduce the no-load voltage to 175V.(Ans : 195V,462.5 Ω,227rpm,34.4 Ω).
  21) The occ of a shunt generator at 750rpm are given below  :
Ish (A)
   3.5
    6
     8
     10
     12
     14
E0 (V)
   200
  300
   360
    400
    440
    464
Calculate 1)The maximum voltage that can be developed at 750rpm when the field  resistance is a)50 Ω , b)35 Ω, 2) The critical field resistance at 750rpm, 3) The field resistance to develop 400V at 750rpm, 4) The critical speed with Rf.(Ans : 1)300V,446V, 2)57.1 Ω,
3) 40 Ω, 4)525rpm).
  22)The data for magnetisation curve of a 6-pole lap connected shunt generator having 940 conductors and driven at a constant speed of 500rpm is as under :
Ish (A)
   0
    2   
    4
    6
    8
   10
  12
   14
E0 (V)
  15
  100
  200
  275
  312
  335
 355
  370
Determine 1)The residual flux ,2)The load supplied by the generator when the terminal voltage is 245V.Armature reaction weakens the field 4%,3)The speed at which the machine just fail to excite . Armature and shunt field resistances are 0.3Ω and 35 Ω respectively.(Ans : 0.001915wb,117.1A,350rpm).
  23)The open circuit characteristics of a DC shunt excited generator is at a speed of 600rpm as under :
Ish (A)
   1
    2   
    3
    4
    5
   6
  7
   8
E0 (V)
  22
   44
  66
   84
  99
  111
 120
  125
  Determine the load current when (1)Terminal potential difference is 120V ,the field resistance is 15Ω at a speed of 600rpm,(2)Terminal voltage is 144V, the field resistance is 18 Ω at a speed of 700rpm. Armature resistance is 0.025 Ω.(Ans : 192A,64A).
24)A DC shunt generator driven at a constant speed of 600rpm has the following occ:
Ish (A)
   1.5
    3  
    4.5
    6
    7.5
   9
E0 (V)
   75
   150
   200
  230
   250
  265
Determine 1) The voltage that can be developed with a field resistance of 30Ω, 2)When the field resistance is 30 Ω ,the terminal voltage of the generator is 240V.Find the voltage drop due to reduction in field current and the load current of the generator .Armature reaction weakens the field by 2%, 3)Determine the voltage drop due to armature reaction when the field resistance is 40 Ω ,terminal voltage is 120V and the armature current is 90A.The armature resistance is 0.07 Ω and brush contact drop =1V per brush.(Ans : 1)265V,2)10V,104.8A,3)21.7V.).
25)A 20kW,450V DC shunt motor has full load current of 85A at 1100rpm.The armature resistance is 0.18 Ω. Determine 1)The internal torque developed ,2)The internal torque developed if the field is suddenly reduced to 80%,3)The steady motor speed in part 2 assembly load torque remaining same.(Ans : 173.2Nm,138.56Nm,1353rpm).
 26) A 220V DC shunt motor runs at 500rpm. When the armature current is 50A. Calculate the speed if the torque is double. Armature resistance is 0.2Ω. (Ans : 476rpm).
27)A 4-pole , 240V wave connected DC shunt motor gives 11.19kW,when running at 1000rpm and drawing armature and field currents  of  50A and 1A respectively. It has 540 conductors .Its resistance is 0.1 Ω, assuming a drop of 1V per brush. Find a) Total torque, b)Useful torque ,c)useful flux per pole ,d) rotational  losses and e) Efficiency.(Ans : 111Nm,106.9Nm,12.9mwb,460W,91.4%).
 28)A 250V DC shunt motor on no-load runs at 1000rpm takes 5A,the field and armature resistances are 250 Ω and 0.25 Ω respectively. Calculate the speed when the motor is loaded such that it takes 41A if the armature reaction weakens the field by 3%.  (Ans : 994rpm).
29)A 6-pole lap wound shunt motor has 500 conductors in the armature. The armature and field resistances of 0.05 Ω and 25 Ω respectively. Find the speed of the motor when it takes 120A from the main dc supply of 100V. Flux per pole is 2xwb.(Ans ; 565rpm).
30) The armature of 6-pole DC shunt motor takes 300A at a speed of 400rpm. The flux per pole is 75mwb.The number of armature turns is 500. The  torque lost in friction and windage losses can be 2.5%.Calculate 1)Armature torque ,2)shunt torque,3)shaft power.(Ans : 3577.5Nm,3488Nm,146kW).
31) A 200V DC shunt motor running at 1000rpm takes an armature current of 17.5A.It is required to reduce the speed to 600rpm.What must be the value of resistance to be inserted in the armature circuit. Armature resistance is 0.4 Ω.(Ans : 4.4 Ω).
32)A 220V DC shunt motor has an armature and field resistances of 0.4Ω and 200Ω respectively .It takes an armature current of 22A and runs at 600rpm.It drives at a load whose torque is constant .Suggest a suitable method to raise the speed to 900rpm and calculate the value of the controllable parameter.(Ans :106.8 Ω).
33)A 220V shunt motor has an armature resistance of 0.5 Ω and takes a current of 40A on full load .By how much must the main flux be reduced to raise the speed by 50%, if the developed torque is continuous.(Ans : 37.5%).
34)A 230V DC shunt motor runs at 800rpm and takes armature current of 50A .Find the resistance to be added to the field circuit to increase speed to 1000rpm at an armature current of 80A.Assume that flux is proportional to field current and armature and shunt field resistance are 0.15 Ω and 250 Ω respectively.(Ans : 69 Ω).
35) A DC series motor having a resistance of 1 Ω drives  a fan for which the torque varies as the squre of the speed. At 220V the set runs at 350rpm and takes 25A. The speed is to be raised to 500rpm by increasing the voltage .Determine the necessary voltage and the corresponding current.(Ans : 433.7V).
36) A separately excited DC shunt motor is driving a  fan whose torque is proportional to the square of the speed. When 100V are applied to the motor , the armature current taken by the motor is 8A. With the speed being 500rpm. At what applied voltage does the speed reach 750rpm and then what is the current drawn by armature? Armature resistance is 1 Ω.(Ans : 18A,156V).
37) When the running on no-load a 400V shunt motor takes 5A.Armature resistance is 0.5 Ω and field resistance is 200Ω. Find the output of the motor and efficiency when running at full load and taking 50A. Also find % change in speed.(Ans : 16.8kW,84.26%,5.98%).
38) The no-load test of a 44.76kW, 220V dc shunt motor gave the following data : Input current is 13.25A,field current is 2.55A,armature resistance is 0.032 Ω and brush voltage drop is 2V. Estimate full load current and efficiency .(Ans : 226A,90%).
39) A 200V dc shunt motor develops an output of 17.158kW,when taking 20.2kW.The field resistance and armature resistances are 50 Ω   and 0.06 Ω respectively. What is the efficiency and input power if output power is 7.46kW?(Ans : 10kW,74.6%).
40) A 250V,14.92kW dc shunt motor has a maximum efficiency of 88% and a speed of 700rpm when delivering 80% of its rated output. The resistance of its shunt field is 100 Ω.  Determine the efficiency and speed when motor draws a current of 78A from mains.(Ans : 86.9%,680rpm).