PowerPoint Presentation: Electrical Engineering Department Government Polytechnic Rajkot POOR VOLTAGE 113V OUT OF 230V VOLTAGE GENERATE IN D.C. SHUNT GENERATOR Project Report Year 2011-12 KAUSHIK SANGHANI : MO. 9909401178 Faculty Guide: Shri R L PATEL Industry Guid : Shri HITESH BAKARANIYA Group No : G19 PowerPoint Presentation: FIRST NAME DAXESH LAST NAME JADAV MOBILE NO. 8905251051 E-MAIL Jadavdaxesh93@gmail.com COLLEGE NAME ADDRESS GOVERNMENT POLYTECHNIC. BHAVNAGAR ROAD, AJI DAM ,RAJKOT BRANCH ELECTRICAL ENGINEERING YEAR 2011 SEMESTER 5 TH TEAM NAME SIGNATURE OF STUDENT DEE_G19 INDUSTRY PARTICULARS -------------------- INDUSTRY CORDINATOR--------------------- NAME ADDRESS SHRI. HITESHBHAI BAKRANIYA MURLIDHAR ELECRICALS BOLBALA MARG OPP. TELEPHONE EXCHANGE, RAJ KOT,360002 CONTACT NO. (O) 9227605542- 9824416925- NAME OF INDUSTRIAL ESTATE MURLIDHAR ELECRICALS RAJKOT,360002 INDUSTRY DEFINED PROBLEM/PROJECT (IDP) STATEMENT FORM STUDENT PARTICULARS PowerPoint Presentation: SR.NO NAME OF STUDENT ENROLL. NO. MOBILE NO 1. CHUDASAMA RAJESH L. (Team Leader) 096200309089 9638423229 2. PANCHAL ANKITKUMAR D. 096200309090 8758009567 3. JADAV DAXESH M. 096200309091 8905251051 4. RAM GOVIND B. 096200309095 9974165699 5. MAGRA CHIRAG N. 096200309098 9712190571 A PROJECT REPORT ON PROBLEM IDENTIFICATION IN POOR VOLTAGE 113v out of 230 VOLTAGE GENERATE IN D.C. SHUNT GENERATOR. Prepared by, PowerPoint Presentation: Sr. PARTICULAR PAGE NO. 1. ACKNOWLEDGEMENT 5 2. PROBLEM SUMMARY 7 3. INTRODUCTION 8 4. DETAIL DISCRIPTION OF PROBLEM 9 CHAPTER 1 REASON OF POOR VOLTAGE GENERATION 9 CHAPTER 2 DIFFERENT TYPES OF TEST IN GENERATOR 10 CHAPTER 3 SPECIFICATION OF D.C. GENERATOR 13 CHAPTER 4 CONSTRUCTION OF D.C. GENERATOR 14 CHAPTER 5 TYPES OF D.C. GENERATOR 15 CHAPTER 6 DIFFERENT TYPES OF WINDING 18 5. EXPECTED OUTCOME 19 INDEX PowerPoint Presentation: PROBLEM SUMMARY As a part of 5 th Semester Electrical subject project-1 in which problem identification in industry, we have visited MURLIDHAR ELECTRICALS Rajkot for the problems The output voltage generated by D.C SHUNT GENERATOR was 113 volt instead of 230 volt. So fault identification in POOR VOLTAGE GENERATION we have taken as part of project -1. PowerPoint Presentation: INTRODUCTION TO M-G SET GENERATOR An electrical generator is a machine which converts mechanical energy in to electrical energy. The energy conservation is based on the principal of the production of dynamically induced emf . Whenever a conductor cuts magnetic flux, dynamically induced emf is produced in it according to faraday’s laws of electromagnetic induction. SQUIRREL CAGE INDUCTION MOTOR The three phase squirrel cage induction motor Consists of a stator and armature winding which is stationary and a rotor or field winding is rotating. Due to a.c voltage applied, current starts flowing in the stator conductor. Due to the three phases supply stator winding produces rotating magnetic field of constant amplitude which is rotating at the constant speed is set up in the air gap between stator and rotor. The rotating magnetic field rotates at a speed called as synchronous speed. PowerPoint Presentation: DETAILED DESCRIPTION OF PROBLEM We have visited electrical machine laboratory, Government Polytechnic Rajkot under the expert guidelines of Shri . Hiteshbhai Bakraniya , service engineer, Murlidhar Electricals Rajkot. We found the poor voltage generation in D.C. shunt Generator. We have measured output voltage with the help of multimeter . It is connected to out-put terminals o f D. C. shunt generator and observed voltage was 113 volt instead of 230 volt. REASON OF POOR VOLTAGE GENERATION Open field winding Short circuited field winding Open armature winding Short circuited armature winding Loose carbon brush contact Lower speed of prime mover Ageing effect No residual magnetism If the field is not connected property Rsh is higher than its critical value PowerPoint Presentation: DIFFERENT TYPES OF TESTS IN D.C GENERATOR CONTINUETY TEST INSULATION RESISTANCE TEST BY MEGGAR GROWLER TEST CONTINUITY TEST This test is performed on D.C shunt generator to check continuity of armature winding and field winding. The continuity test is carried out with the help of Test lamp. If the armature winding / field winding is continuous, the bulb will glow. If the armature winding / field windings is opened the bulb will not glow. PowerPoint Presentation: INSULATION RESISTANCE TEST BY MEGGER This Test is Conducted to Verify Whether the insulation of winding is proper or not. The object of this test is to ensure that the insulation between coils, between inter turns of coils and between conductors and body should be sound. PowerPoint Presentation: Connect L terminal of megger with one end of coil and E terminal of megger with another end of same coil of armature or field winding. Rotate the megger handle at approximate 145 rpm steadily and observe the reading in a dial of a megger . It should indicate zero.It means coil is continues. Connect L terminal of megger with one end of coil and E terminal of megger with another end of the coil of winding or with body of the machine. Rotate the megger handle at approximate 145 rpm steadily and observe the reading in a dial of a megger . It should not be less than insulation resistance. The insulation resistance between winding and earth should not be less than 1.0 Mega ohm. If I.R. is below 1 M.ohm, winding is faulty. PowerPoint Presentation: GROWLER TEST: The growler test is performed to find out whether the armature winding or field winding turns are internally short circuited or not. In growler test the armature is placed on growler OR it is placed inside field pole and holds a hacksaw blade against armature core while slowly rotating armature, a short circuited armature causes blade to be vibrate and be attracted to core. The part of armature winding which is short circuited must be replaced. (ARMATURE WNDING TEST USING GROWLER) PowerPoint Presentation: SPECIFICATION OF D.C. GENERATOR 3 KVA , 230 Volt, 1500 RPM Shunt Field, Continuous Rating. (SQUIRREL CAGE INDUCTION MOTOR AND GENENRATOR PANNEL SET) PowerPoint Presentation: CONSTRUCTION OF D.C SHUNT GENERATOR ( CONSTRUCTION OF GENERATOR) PowerPoint Presentation: PRINCIPLE OF A D.C. GENENRATOR A DC Generator operates on the principal of dynamically induced in e.m.f in conductor. The dynamic induction of e.m.f can be explained with the help of faradays laws of electromagnetic induction. (FLEMMING’S RIGHT HAND RULE) TYPES OF D.C GENERATOR GENERATOR 1. Separately excited generator 2. Self exited generator Shunt generator Series generator Compound generator Cumulative compound generator Differential compound generator PowerPoint Presentation: When you open out the D.C generator you will able to see the different parts of. YOKE FIELD WINDING POLES ARMATURE COMMUTATOR, BRUSHES AND GEAR BEARINGS LIFTING EYE 1. YOKE : Yoke is also called frame. It provides protection to the rotating and ineer parts of the machine from moisture, dust etc. Yoke is an iron body Wich provides low reluctance path for the flux. This is an essential to complete the magnetic circuit. 2. FIELD WINDING The coils wound around the pole cores are called field coils.The field coils are connected in series to form the field winding. Current is passed through the field winding in a specific direction , to magnetize the poles and pole shoes. The magnetic flux is thus produced in the air gap between the pole shoes and armature. PowerPoint Presentation: 3. POLES A Poles of a generator is an electromagnet. The field winding is wound surround the poles Poles produce the magnetic flux when the field winding is excited. 4. ARMATURE CORE Armature core is a cylindrical drum mounted on the shaft. It consits number of slots over its periphery. All these slots are parallel to the shaft axis. Armature core provides a low reluctance path for the flux produced by the field winding. 5. ARMATURE WINDING The armature conductor made of copper are placed in the armature slots present on the periphery of armature core. Armature conducters are interconected to form the armature winding., When the armature winding is rotated using a prime mover, it cuts the magnetic flux lines and voltage gets indused in it. PowerPoint Presentation: 6. COMMUTATOR A commutator is a cylindrical drum mounted on the shaft along with the armature core.It is made of large number of wedge shaped segments of hard drawn copper. The armature winding is tapped at various points and these tappings are successively connected to various segments of the commutator . 7. BRUSHES Current is conducted from the armature to the external load by the carbon brushes which are held against the surface of commutator by spring. Brushes wear with time. Hence they should be inspected regularly and replaced occasionally. PowerPoint Presentation: DIFFERENT TYPES OF WINDING The windings are designed in such a way that the emf induse in the condutrs of each coil side should be additve and the generator will generate desired amount of emf . Following winding are used in D.C generator. SIMPLEX LAP WINDING SIMPLEX WAVE WINDING PowerPoint Presentation: SIMPLEX LAP WINDING : In lap winding the finishing or back side or first coil is connected to starting end front side of next coil. The junction is connected to a commutator sgment . Thus all the coils are connected in progressive style or retrogressive style. SIMPLEX WAVE WINDING In simple wave winding the front side of the coil is placed one pole and its back side is placed under the text of opposite polaity and it is connected to the commutator segment. With the same commutator segment the end of front side of the next coil connected. PowerPoint Presentation: EXPECTED OUTCOME The generator fault of poor voltage generation is found by performing different tests. Open armature winding OR field winding is checked by continuity test. Insulation resistance of winding is measured using megger . Physical checking of carbon brush. Interturns short-circuit of Armature winding or field winding is checked by performing growler test. Routing maintenance of the machine should be done.