Single Phase Induction Motors

Size: px
Start display at page:

Download "Single Phase Induction Motors"

Transcription

1 Single Phase Induction Motors Prof. T. H. Panchal Asst. Professor Department of Electrical Engineering Institute of Technology Nirma University, Ahmedabad

2 Introduction As the name suggests, these motors are used on singlephase supply. Single phase motors are the most familiar of all electric motors because they are extensively used in home appliances, shops, offices etc. It is true that single phase motors are less efficient substitute for 3-phase motors but 3-phase power is normally not available except in large commercial and industrial establishments. Since electric power was originally generated and distributed for lighting only, millions of homes were given single-phase supply. This led to the development of single-phase motors. Even where 3-phase mains are present, the single-phase supply may be obtained by using one of the three lines and the neutral.

3 Types of Single Phase Motors Single-phase motors are generally built in the fractionalhorsepower range and may be classified into the following four basic types: 1. Single-phase induction motors (i) split-phase type (ii) capacitor type (iii) shaded-pole type. A.C. series motor or universal motor 3. Repulsion motors (i) Repulsion-start induction-run motor (ii) Repulsion-induction motor 4. Synchronous motors (i) Reluctance motor (ii) Hysteresis motor

4 Single Phase Induction Motors A single phase induction motor is very similar to a 3- phase squirrel cage induction motor. It has (i) a squirrel-cage rotor identical to a 3-phase motor and (ii) a single-phase winding on the stator. Unlike a 3-phase induction motor, a single-phase induction motor is not self starting but requires some starting means. The single-phase stator winding produces a magnetic field that pulsates in strength in a sinusoidal manner. The field polarity reverses after each half cycle but the field does not rotate. Consequently, the alternating flux cannot produce rotation in a stationary squirrel-cage rotor.

5 However, if the rotor of a single-phase motor is rotated in one direction by some mechanical means, it will continue to run in the direction of rotation. As a matter of fact, the rotor quickly accelerates until it reaches a speed slightly below the synchronous speed. Once the motor is running at this speed, it will continue to rotate even though single-phase current is flowing through the stator winding. This method of starting is generally not convenient for large motors.

6 Fig. (1) 1-phase supply Stator winding Squirrel cage rotor

7 Fig. (1) shows single-phase induction motor having a squirrel cage rotor and a single phase distributed stator winding. Such a motor inherently does not develop any starting torque and, therefore, will not start to rotate if the stator winding is connected to single-phase a.c. supply. However, if the rotor is started by auxiliary means, the motor will quickly attain the final speed. This strange behavior of single-phase induction motor can be explained on the basis of double-field revolving theory.

8 Double Field Revolving Theory This theory makes the use of idea that an alternating uni-axial quantity can be represented by two oppositely rotating vectors of half magnitude. Accordingly, an alternating sinusoidal flux can be represented by two revolving fluxes, each equal to the value of the alternating flux and each rotating synchronously in opposite direction. As shown in fig. (a), let the alternating flux have a maximum value of ϕ m. Its component fluxes A and B will each be equal to ϕ m / revolving in anticlockwise and clockwise directions respectively.

9

10 After some time, when A and B would have rotated through angle +θ and θ, as in fig. (b), the resultant flux would be m cos cos m After a quarter cycle rotation, fluxes A and B will be oppositely directed as shown in fig. (c) so that the resultant flux would be zero. After half a cycle, fluxes A and B will have a resultant of - x ϕ m / = ϕ m. After three quarter of a cycle, again the resultant is zero as shown in fig. (e) and so on. If we plot the values of resultant flux against θ between limits θ = 0 to θ = 360, then a curve similar to the one shown in fig. () is obtained. That is why an alternating flux can be looked upon as composed of two revolving fluxes, each of half the value and revolving synchronously in opposite directions.

11

12 If the slip of the rotor is s w.r.t. the forward rotating flux (i.e. one which rotates in the same direction as rotor) then its slip w.r.t. the backward rotating flux is ( - s). Each of the two component fluxes, while revolving round the rotor, induces an emf and this produces its own torque. The two torques (called forward and backward torques) are oppositely directed, so that the resultant torque is equal to their difference as shown in Fig. (3)

13

14 Power developed by a rotor is If N is the rotor r.p.s. then torque is given by 1 R I s s P g s R I k s R I N T s N N Now R I s s N T s g s g 1 ) (1 1 1

15 Hence the forward and backward torques are given by Total Torque watt synch s R I T watt synch s R I T s R I K T and s R I K T b f b f.. T f T b T

16 Fig. shows both torques and the resultant torque for slips between zero and +. At standstill, s = 1 and (-s) = 1. Hence, T f and T b are numerically equal but, being oppositely directed, produce no resultant torque. That explains why there is no starting torque in a single phase induction motor. However, if the rotor is started somehow, say, in the clockwise direction, the clockwise torque starts increasing and, at the same time, the anticlockwise torque starts decreasing. Hence, there is a certain amount of net torque in the clockwise direction which accelerates the motor to full speed.

17 Making Single Phase IM Self-starting A single phase IM is not self starting. To make the motor selfstarting, it is temporarily converted into a two phase motor during starting period. For this purpose, stator of single phase IM is provided with an extra winding, known as starting( or auxiliary) winding, in addition to the main or running winding. The two windings are spaced 90 electrically apart and are connected in parallel across the single phase supply. It is so arranged that the phase difference between the currents in the two stator windings is very large. Hence, the motor behaves like a two phase motor. These two currents produce a revolving flux and hence make the motor self-starting.

18 Main Winding Rotor Starting Winding Stator Air Gap

19 There are many methods by which the necessary phase difference between two currents can be created. 1. Split Phase Induction Motor In split phase machine, the main winding has low resistance but high reactance whereas the starting winding has high resistance, but low reactance. The resistance of the starting winding may be increased either by connecting a high resistance R in series with it or by choosing high resistance fine copper wire for winding. Hence, as shown in fig. the current I s drawn by the starting winding lags behind the applied voltage V by a small angle whereas current I m taken by the main winding lags behind V by a very large angle.

20 Single Phase Supply Im Main Starting Winding Winding Is R S Rotor

21 Phase difference between I s and I m is made as large as possible because the starting torque of this motor is proportional to sinα. A centrifugal switch S is connected in series with the starting winding and is located inside the motor. Its function is to automatically disconnect the starting winding from the supply when the motor has reached 70 to 80% of its full load speed.

22

23 As seen from the torque/speed characteristic of this motor, the starting torque is 150 to 00% of the full load torque with a starting current of 6 to 8 times the full load current. These motors are often used in preference to the costlier capacitor start motors. Applications: Fans and blowers Centrifugal pumps Washing machines Small machine tools Domestic refrigerators Size ranges from 40 to 50 W with speeds ranging from 3450 to 865 rpm.

24 . Capacitor-start Induction-run single phase IM In these motors, necessary phase difference between I s and I m is produced by connecting a capacitor in series with the starting winding. The capacitor is generally of electrolytic type and is mounted on the outside of the motor as a separate unit. Starting Winding Im Main Winding Single Phase Supply Is C S Rotor

25 Capacitor Is S Im Supply Running Starting

26 The capacitor is designed for extremely short duty service and is guaranteed for not more than 0 periods of operation per hour, each period not to exceed 3 seconds. When the motor reaches about 75% of full speed, the centrifugal switch S opens and cuts out both starting winding and the capacitor from the supply, thus leaving only the running winding across the supply. Current Im drawn by the main winding lags the supply voltage V by a large angle whereas Is leads V by a certain angle. The two currents are out of phase with each other by about 80% as compared to nearly 30 for a split phase machine. Their resultant current I is small and is almost in phase with V.

27 Since the torque developed by a split phase motor is proportional to the sine of the angle between I s and I m, it is obvious that the increase in the angle alone increases the starting torque to nearly twice the value developed by a standard split phase induction motor.

28 Capacitor Start and Run Motor In this motor, starting winding and capacitor are connected in the circuit at all times. Advantages of leaving capacitor permanently in circuit are Improvement of over load capacity of the motor Higher power factor Higher efficiency Quieter running of the motor Motors which start and run with one value of capacitance in the circuit are called single-value capacitor run motors Other which start with high value of capacitance but run with a low value of capacitance are known as two-value capacitor run motors.

29 Single Value Capacitor Run Motor Run Is Im Supply Start C Rotor

30 Single Value Capacitor Run Motor

31 Single Value Capacitor Run Motor Forward Reverse A B Supply

32 Two Value Capacitor Run Motor A B Low S Supply Running Starting

Single Phase Induction Motor. Dr. Sanjay Jain Department Of EE/EX

Single Phase Induction Motor. Dr. Sanjay Jain Department Of EE/EX Single Phase Induction Motor Dr. Sanjay Jain Department Of EE/EX Application :- The single-phase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills,

More information

Part- A Objective Questions (10X1=10 Marks)

Part- A Objective Questions (10X1=10 Marks) Dr. Mahalingam College of Engineering and Technology, Pollachi-3 (An Autonomous Institution) CCET 3(2016Regulation) Name of Programme: B.E. (EEE) Course Code&Course Title: 16EET41 & Synchronous & Induction

More information

10. Starting Method for Induction Motors

10. Starting Method for Induction Motors 10. Starting Method for Induction Motors A 3-phase induction motor is theoretically self starting. The stator of an induction motor consists of 3-phase windings, which when connected to a 3-phase supply

More information

Most home and business appliances operate on single-phase AC power. For this reason, singlephase AC motors are in widespread use.

Most home and business appliances operate on single-phase AC power. For this reason, singlephase AC motors are in widespread use. Chapter 5 Most home and business appliances operate on single-phase AC power. For this reason, singlephase AC motors are in widespread use. A single-phase induction motor is larger in size, for the same

More information

ESO 210 Introduction to Electrical Engineering

ESO 210 Introduction to Electrical Engineering ESO 210 Introduction to Electrical Engineering Lectures-37 Polyphase (3-phase) Induction Motor 2 Determination of Induction Machine Parameters Three tests are needed to determine the parameters in an induction

More information

AC MOTOR TYPES. DESCRIBE how torque is produced in a single-phase AC motor. EXPLAIN why an AC synchronous motor does not have starting torque.

AC MOTOR TYPES. DESCRIBE how torque is produced in a single-phase AC motor. EXPLAIN why an AC synchronous motor does not have starting torque. Various types of AC motors are used for specific applications. By matching the type of motor to the appropriate application, increased equipment performance can be obtained. EO 1.5 EO 1.6 EO 1.7 EO 1.8

More information

Institute of Technology, Nirma University B. Tech. Sem. V: Electrical Engineering 2EE305: ELECTRICAL MACHINES II. Handout: AC Commutator Motors

Institute of Technology, Nirma University B. Tech. Sem. V: Electrical Engineering 2EE305: ELECTRICAL MACHINES II. Handout: AC Commutator Motors Institute of Technology, Nirma University B. Tech. Sem. V: Electrical Engineering 2EE305: ELECTRICAL MACHINES II Handout: AC Commutator Motors Prepared by: Prof. T. H. Panchal Learning Objective: Introduction

More information

14 Single- Phase A.C. Motors I

14 Single- Phase A.C. Motors I Lectures 14-15, Page 1 14 Single- Phase A.C. Motors I There exists a very large market for single-phase, fractional horsepower motors (up to about 1 kw) particularly for domestic use. Like many large volume

More information

EEE3441 Electrical Machines Department of Electrical Engineering. Lecture. Introduction to Electrical Machines

EEE3441 Electrical Machines Department of Electrical Engineering. Lecture. Introduction to Electrical Machines Department of Electrical Engineering Lecture Introduction to Electrical Machines 1 In this Lecture Induction motors and synchronous machines are introduced Production of rotating magnetic field Three-phase

More information

Lecture 20: Stator Control - Stator Voltage and Frequency Control

Lecture 20: Stator Control - Stator Voltage and Frequency Control Lecture 20: Stator Control - Stator Voltage and Frequency Control Speed Control from Stator Side 1. V / f control or frequency control - Whenever three phase supply is given to three phase induction motor

More information

Unit 34 Single-Phase Motors

Unit 34 Single-Phase Motors Unit 34 Single-Phase Motors Objectives: Unit 34 Single-Phase Motors List the different types of split-phase motors. Discuss the operation of split-phase motors. Reverse the direction of rotation of a splitphase

More information

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING QUESTION BANK 16EET41 SYNCHRONOUS AND INDUCTION MACHINES UNIT I SYNCHRONOUS GENERATOR 1. Why the stator core is laminated? 2. Define voltage regulation

More information

Single-Phase AC Induction Squirrel Cage Motors. Permanent Magnet Series Wound Shunt Wound Compound Wound Squirrel Cage. Induction.

Single-Phase AC Induction Squirrel Cage Motors. Permanent Magnet Series Wound Shunt Wound Compound Wound Squirrel Cage. Induction. FAN ENGINEERING Information and Recommendations for the Engineer Twin City Fan FE-1100 Single-Phase AC Induction Squirrel Cage Motors Introduction It is with the electric motor where a method of converting

More information

APGENCO/APTRANSCO Assistant Engineer Electrical Previous Question Papers Q.1 The two windings of a transformer is conductively linked. inductively linked. not linked at all. electrically linked. Q.2 A

More information

Date: Name: ID: LABORATORY EXPERIMENT NO. 8 INDUCTION MOTOR/GENERATOR 8-1

Date: Name: ID: LABORATORY EXPERIMENT NO. 8 INDUCTION MOTOR/GENERATOR 8-1 Date: Name: ID: LABORATORY EXPERIMENT NO. 8 INDUCTION MOTOR/GENERATOR 8-1 OBJECT 1. To determine the general performance of a squirrel motors 2. To observe the characteristics of induction generators.

More information

Pretest Module 21 Unit 4 Single-Phase Motors

Pretest Module 21 Unit 4 Single-Phase Motors Pretest Module 21 Unit 4 Single-Phase Motors 1. What are the four main components of a single-phase motor? Rotor, stator, centrifugal switch, end bells and bearings 2. How is a rotating field created in

More information

Unit III A.C. Machines Explain the construction of induction motor. General principle Construction Stator:

Unit III A.C. Machines Explain the construction of induction motor. General principle Construction Stator: Unit III A.C. Machines - Principle of operation of 3-phase Induction Motor Torque, slips characteristics- Speed control methods Single-phase Induction motor starting methods Principle of operation of Alternators.

More information

Electrical Machines II. Week 5-6: Induction Motor Construction, theory of operation, rotating magnetic field and equivalent circuit

Electrical Machines II. Week 5-6: Induction Motor Construction, theory of operation, rotating magnetic field and equivalent circuit Electrical Machines II Week 5-6: Induction Motor Construction, theory of operation, rotating magnetic field and equivalent circuit Asynchronous (Induction) Motor: industrial construction Two types of induction

More information

The Wound-Rotor Induction Motor Part I

The Wound-Rotor Induction Motor Part I Experiment 1 The Wound-Rotor Induction Motor Part I OBJECTIVE To examine the construction of the three-phase wound-rotor induction motor. To understand exciting current, synchronous speed and slip in a

More information

Unit III-Three Phase Induction Motor:

Unit III-Three Phase Induction Motor: INTRODUCTION Unit III-Three Phase Induction Motor: The three phase induction motor runs on three phase AC supply. It is an ac motor. The power is transferred by means of induction. So it is also called

More information

2. Draw the speed-torque characteristics of dc shunt motor and series motor. (May2013) (May 2014)

2. Draw the speed-torque characteristics of dc shunt motor and series motor. (May2013) (May 2014) UNIT 2 - DRIVE MOTOR CHARACTERISTICS PART A 1. What is meant by mechanical characteristics? A curve is drawn between speed-torque. This characteristic is called mechanical characteristics. 2. Draw the

More information

ECET 211 Electric Machines & Controls Lecture 5-1 Electric Motors. Lecture 5-1 Electric Motors

ECET 211 Electric Machines & Controls Lecture 5-1 Electric Motors. Lecture 5-1 Electric Motors ECET 211 Electric Machines & Controls Lecture 5-1 Electric Motors (2 of 4) Text Book: Chapter 5 Electric Motors, Electric Motors and Control Systems, by Frank D. Petruzella, published by McGraw Hill, 2015.

More information

ELECTRICAL MAINTENANCE

ELECTRICAL MAINTENANCE ELECTRICAL MAINTENANCE II PRACTICAL JOURNAL DATA 1 EXPERIMENT NO. 1 AIM: TO FIND VOLTAGE RATIO OF A GIVEN TRANSFORMER. CIRCUIT DIAGRAM: OBSERVATION TABLE: Sr.No. 1 2 3 4 Primary Voltage (V 1 ) Secondary

More information

SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES UNIT OBJECTIVES 3/21/2012

SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES UNIT OBJECTIVES 3/21/2012 SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES After studying this unit, the reader should be able to Describe the different types of open single-phase motors used to drive

More information

Fachpraktikum Elektrische Maschinen. Theory of Induction Machines

Fachpraktikum Elektrische Maschinen. Theory of Induction Machines Fachpraktikum Elektrische Maschinen Theory of Induction Machines Prepared by Arda Tüysüz January 2013 Fundamentals Induction machines (also known as asynchronous machines) are by far the most common type

More information

ROTATING MAGNETIC FIELD

ROTATING MAGNETIC FIELD Chapter 5 ROTATING MAGNETIC FIELD 1 A rotating magnetic field is the key to the operation of AC motors. The magnetic field of the stator is made to rotate electrically around and around in a circle. Stator

More information

Stator rheostat, Autotransformer Star to Delta starter and rotor resistance starter.

Stator rheostat, Autotransformer Star to Delta starter and rotor resistance starter. UNIT-IV 1.What are the types of starters? Stator rheostat, Autotransformer Star to Delta starter and rotor resistance starter. 2. List out the methods of speed control of cage type 3-phase induction motor?

More information

PHY 152 (ELECTRICITY AND MAGNETISM)

PHY 152 (ELECTRICITY AND MAGNETISM) PHY 152 (ELECTRICITY AND MAGNETISM) ELECTRIC MOTORS (AC & DC) ELECTRIC GENERATORS (AC & DC) AIMS Students should be able to Describe the principle of magnetic induction as it applies to DC and AC generators.

More information

Starting of Induction Motors

Starting of Induction Motors 1- Star Delta Starter The method achieved low starting current by first connecting the stator winding in star configuration, and then after the motor reaches a certain speed, throw switch changes the winding

More information

Motor Basics AGSM 325 Motors vs Engines

Motor Basics AGSM 325 Motors vs Engines Motor Basics AGSM 325 Motors vs Engines Motors convert electrical energy to mechanical energy. Engines convert chemical energy to mechanical energy. 1 Motors Advantages Low Initial Cost - $/Hp Simple &

More information

Synchronous Generators I. Spring 2013

Synchronous Generators I. Spring 2013 Synchronous Generators I Spring 2013 Construction of synchronous machines In a synchronous generator, a DC current is applied to the rotor winding producing a rotor magnetic field. The rotor is then turned

More information

Induction machine characteristics and operation. Induction Machines

Induction machine characteristics and operation. Induction Machines Induction Machines 1.1 Introduction: An essential feature of the operation of the synchronous machine is that the rotor runs at the same speed as the rotating magnetic field produced by the stator winding.

More information

UNIT 2. INTRODUCTION TO DC GENERATOR (Part 1) OBJECTIVES. General Objective

UNIT 2. INTRODUCTION TO DC GENERATOR (Part 1) OBJECTIVES. General Objective DC GENERATOR (Part 1) E2063/ Unit 2/ 1 UNIT 2 INTRODUCTION TO DC GENERATOR (Part 1) OBJECTIVES General Objective : To apply the basic principle of DC generator, construction principle and types of DC generator.

More information

Principles of Electrical Engineering

Principles of Electrical Engineering D.C GENERATORS Principle of operation of D.C machines, types of D.C Generators, e.m.f equation of D.C Generator, O.C.C of a D.C Shunt Generator, Load characteristics of D.C.Generators GENERATOR PRINCIPLE:

More information

Synchronous Generators I. EE 340 Spring 2011

Synchronous Generators I. EE 340 Spring 2011 Synchronous Generators I EE 340 Spring 2011 Construction of synchronous machines In a synchronous generator, a DC current is applied to the rotor winding producing a rotor magnetic field. The rotor is

More information

Table of Contents Lesson One Lesson Two Lesson Three Lesson Four Lesson Five Lesson Six Lesson Seven Lesson Eight Lesson Nine Lesson Ten

Table of Contents Lesson One Lesson Two Lesson Three Lesson Four Lesson Five Lesson Six Lesson Seven Lesson Eight Lesson Nine Lesson Ten Table of Contents Lesson One Lesson Two Lesson Three Introduction to Single-Phase Motors...3 Split-Phase Motors...21 Capacitor Motors...37 Lesson Four Lesson Five Lesson Six Repulsion Motors...55 Universal

More information

VIII. Three-phase Induction Machines (Asynchronous Machines) Induction Machines

VIII. Three-phase Induction Machines (Asynchronous Machines) Induction Machines VIII. Three-phase Induction Machines (Asynchronous Machines) Induction Machines 1 Introduction Three-phase induction motors are the most common and frequently encountered machines in industry simple design,

More information

Chapter 2: AC Gearmotors and Motors

Chapter 2: AC Gearmotors and Motors Chapter : AC Gearmotors and Motors Although commutator and brush assemblies may be used in some types of alternating current (AC) gearmotors and motors (series/universal wound), brushless induction-type

More information

Electrical Machines -II

Electrical Machines -II Objective Type Questions: 1. Basically induction machine was invented by (a) Thomas Alva Edison (b) Fleming (c) Nikola Tesla (d) Michel Faraday Electrical Machines -II 2. What will be the amplitude and

More information

General Purpose Permanent Magnet Motor Drive without Speed and Position Sensor

General Purpose Permanent Magnet Motor Drive without Speed and Position Sensor General Purpose Permanent Magnet Motor Drive without Speed and Position Sensor Jun Kang, PhD Yaskawa Electric America, Inc. 1. Power consumption by electric motors Fig.1 Yaskawa V1000 Drive and a PM motor

More information

Dev Bhoomi Institute Of Technology LABORATORY Department of Electrical And Electronics Engg. Electro-mechanical Energy Conversion II

Dev Bhoomi Institute Of Technology LABORATORY Department of Electrical And Electronics Engg. Electro-mechanical Energy Conversion II REV. NO. : REV. DATE : PAGE: 1 Electro-mechanical Energy Conversion II 1. To perform no load and blocked rotor tests on a three phase squirrel cage induction motor and determine equivalent circuit. 2.

More information

Synchronous Motor Drives

Synchronous Motor Drives UNIT V SYNCHRONOUS MOTOR DRIVES 5.1 Introduction Synchronous motor is an AC motor which rotates at synchronous speed at all loads. Construction of the stator of synchronous motor is similar to the stator

More information

EE6351 ELECTRIC DRIVES AND CONTROL UNIT-1 INTRODUTION

EE6351 ELECTRIC DRIVES AND CONTROL UNIT-1 INTRODUTION EE6351 ELECTRIC DRIVES AND CONTROL UNIT-1 INTRODUTION 1. What is meant by drive and electric drive? Machines employed for motion control are called drives and may employ any one of the prime movers for

More information

2 Principles of d.c. machines

2 Principles of d.c. machines 2 Principles of d.c. machines D.C. machines are the electro mechanical energy converters which work from a d.c. source and generate mechanical power or convert mechanical power into a d.c. power. These

More information

Regulation: R16 Course & Branch: B.Tech EEE

Regulation: R16 Course & Branch: B.Tech EEE SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (Descriptive) Subject with Code : Electrical Machines-II (16EE215) Regulation: R16 Course & Branch: B.Tech

More information

DC CIRCUITS ELECTROMAGNETISM

DC CIRCUITS ELECTROMAGNETISM DC CIRCUITS 1. State and Explain Ohm s Law. Write in brief about the limitations of Ohm s Law. 2. State and explain Kirchhoff s laws. 3. Write in brief about disadvantages of series circuit and advantages

More information

Unit-IV. 1. Explain the operation, characteristics and application of DC and AC servo motor.

Unit-IV. 1. Explain the operation, characteristics and application of DC and AC servo motor. Unit-IV Special Machines - Servo motor DC and AC servomotors; stepper motors variable reluctance and permanent magnet stepper motors; single phase synchronous motor reluctance motor and hysteresis motor

More information

II/IV B.Tech(Regular) DEGREE EXAMINATION. Electronics & Instrumentation Engineering

II/IV B.Tech(Regular) DEGREE EXAMINATION. Electronics & Instrumentation Engineering SCHME OF EVALUTION II/IV B.Tech(Regular) DEGREE EXAMINATION JUNE,2016 EI ET 403 Electrical Technology Electronics & Instrumentation Engineering Max.Marks :60 marks -----------------------------------------------------------------------------------------------------------

More information

(d) None of the above.

(d) None of the above. Dr. Mahalingam College of Engineering and Technology, Pollachi-3 (An Autonomous Institution affiliated to Anna niversity) CCET II (2016 Regulation) Name of Programme: B.E. (EEE) Course Code & Course Title:

More information

AE105 PRINCIPLES OF ELECTRICAL ENGINEERING JUNE 2014

AE105 PRINCIPLES OF ELECTRICAL ENGINEERING JUNE 2014 Q.2 a. Explain in detail eddy current losses in a magnetic material. Explain the factors on which it depends. How it can be reduced? IETE 1 b. A magnetic circuit with a single air gap is shown in given

More information

SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR

SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (DESCRIPTIVE) Subject with Code : ET(16EE212) Year & Sem: II-B.Tech & II-Sem UNIT I DC GENERATORS Course

More information

Induction motors advantages of induction motors squirrel cage motor

Induction motors advantages of induction motors squirrel cage motor AC Motors With AC currents, we can reverse field directions without having to use brushes. This is good news, because we can avoid the arcing, the ozone production and the ohmic loss of energy that brushes

More information

CHAPTER THREE DC MOTOR OVERVIEW AND MATHEMATICAL MODEL

CHAPTER THREE DC MOTOR OVERVIEW AND MATHEMATICAL MODEL CHAPTER THREE DC MOTOR OVERVIEW AND MATHEMATICAL MODEL 3.1 Introduction Almost every mechanical movement that we see around us is accomplished by an electric motor. Electric machines are a means of converting

More information

CHAPTER 6 INTRODUCTION TO MOTORS AND GENERATORS

CHAPTER 6 INTRODUCTION TO MOTORS AND GENERATORS CHAPTER 6 INTRODUCTION TO MOTORS AND GENERATORS Objective Describe the necessary conditions for motor and generator operation. Calculate the force on a conductor carrying current in the presence of the

More information

Contents. Review of Electric Circuitd. Preface ;

Contents. Review of Electric Circuitd. Preface ; Preface ; Chapter 1 Review of Electric Circuitd 1.1 Introduction, 1 1.2 Direct Circuit Current, 1 1.2.1 Voltage, 3 1.2.2 Power, 3 1.2.3 Ohm's Law, 5 1.2.4 KirchhofTs Laws, 5 1.2.4.1 Kirchhoff s Current

More information

9/7/2010. Chapter , The McGraw-Hill Companies, Inc. MOTOR CLASSIFICATION. 2010, The McGraw-Hill Companies, Inc.

9/7/2010. Chapter , The McGraw-Hill Companies, Inc. MOTOR CLASSIFICATION. 2010, The McGraw-Hill Companies, Inc. Chapter 2 MOTOR CLASSIFICATION 1 In general, motors are classified according to the type of power used (AC or DC) and the motor's principle of operation. AC DC Motor Family Tree 2 DC MOTOR CONNECTIONS

More information

INTRODUCTION Principle

INTRODUCTION Principle DC Generators INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy by using the principle of magnetic induction. Principle Whenever a conductor is moved within a

More information

SYNCHRONOUS GENERATOR (ALTERNATOR)

SYNCHRONOUS GENERATOR (ALTERNATOR) i SYLLABUS osmania university UNIT - I SYNCHRONOUS MACHINES Constructional Details, Types of Windings, Winding Factors, EMF Equation, Fractional Pitch and Fractional Slot Windings, Suppression of Harmonics

More information

Unit-II Synchronous Motor

Unit-II Synchronous Motor Unit-II Synchronous Motor CONSTRUCTION OF THREE PHASE SYNCHRONOUS MOTOR PRINCIPLE OF OPERATION Prepared By P.Priyadharshini Ap/EEE - 1 - Note: 1. The average torque exerted on the rotor of synchronous

More information

Pretest Module 21 Units 1-4 AC Generators & Three-Phase Motors

Pretest Module 21 Units 1-4 AC Generators & Three-Phase Motors Pretest Module 21 Units 1-4 AC Generators & Three-Phase Motors 1. What are the two main parts of a three-phase motor? Stator and Rotor 2. Which part of a three-phase squirrel-cage induction motor is a

More information

Circuit Diagram For Speed Control Of Slip Ring Induction Motor

Circuit Diagram For Speed Control Of Slip Ring Induction Motor Circuit Diagram For Speed Control Of Slip Ring Induction Motor A wound-rotor motor is a type of induction motor where the rotor windings are Compared to a squirrel-cage rotor, the rotor of the slip ring

More information

Introduction: Electromagnetism:

Introduction: Electromagnetism: This model of both an AC and DC electric motor is easy to assemble and disassemble. The model can also be used to demonstrate both permanent and electromagnetic motors. Everything comes packed in its own

More information

Doubly fed electric machine

Doubly fed electric machine Doubly fed electric machine Doubly fed electric machines are electric motors or electric generators that have windings on both stationary and rotating parts, where both windings transfer significant power

More information

Question 2: Around the bar magnet draw its magnetic fields. Answer:

Question 2: Around the bar magnet draw its magnetic fields. Answer: Chapter 13: Magnetic Effects of Electric Current Question 1: What is the reason behind the compass needle is deflected when it is brought close to the bar magnet? Compass needles work as a small bar magnet;

More information

INDUCTION MOTOR. There is no physical electrical connection to the secondary winding, its current is induced

INDUCTION MOTOR. There is no physical electrical connection to the secondary winding, its current is induced INDUCTION MOTOR INTRODUCTION An induction motor is an alternating current motor in which the primary winding on one member (usually the stator) is connected to the power source and a secondary winding

More information

DC MOTORS DC Motors DC Motor is a Machine which converts Electrical energy into Mechanical energy. Dc motors are used in steel plants, paper mills, textile mills, cranes, printing presses, Electrical locomotives

More information

DHANALAKSHMI COLLEGE OF ENGINEERING MANIMANGALAM. TAMBARAM, CHENNAI B.E. ELECTRICAL AND ELECTRONICS ENGINEERING

DHANALAKSHMI COLLEGE OF ENGINEERING MANIMANGALAM. TAMBARAM, CHENNAI B.E. ELECTRICAL AND ELECTRONICS ENGINEERING DHANALAKSHMI COLLEGE OF ENGINEERING MANIMANGALAM. TAMBARAM, CHENNAI B.E. ELECTRICAL AND ELECTRONICS ENGINEERING V SEMESTER EE2305 ELECTRICAL MACHINES II LABORATORY LABORATORY MANUAL 1 CONTENT S. No. Name

More information

Experiment 3. The Direct Current Motor Part II OBJECTIVE. To locate the neutral brush position. To learn the basic motor wiring connections.

Experiment 3. The Direct Current Motor Part II OBJECTIVE. To locate the neutral brush position. To learn the basic motor wiring connections. Experiment 3 The Direct Current Motor Part II OBJECTIVE To locate the neutral brush position. To learn the basic motor wiring connections. To observe the operating characteristics of series and shunt connected

More information

Induction type Energy meter Construction

Induction type Energy meter Construction Induction type Energy meter Construction The four main parts of an energy meter are: Driving system Moving system Braking system and Registering system The construction is as shown below: Fig. Construction

More information

Special-Purpose Electric Machines

Special-Purpose Electric Machines Special-Purpose Electric Machines The machines introduced in this lecture are used in many applications requiring fractional horsepower, or the ability to accurately control position, velocity or torque.

More information

To study the constructional features of ammeter, voltmeter, wattmeter and energymeter.

To study the constructional features of ammeter, voltmeter, wattmeter and energymeter. Experiment o. 1 AME OF THE EXPERIMET To study the constructional features of ammeter, voltmeter, wattmeter and energymeter. OBJECTIVE 1. To be conversant with the constructional detail and working of common

More information

Pump ED 101. Power Factor (Part 2) - - Electricity Behaving Better

Pump ED 101. Power Factor (Part 2) - - Electricity Behaving Better Pump ED 101 Power Factor (Part 2) - - Electricity Behaving Better Joe Evans, Ph.D http://www.pumped101.com Last month we took a close look at the flow of voltage and current in purely resistive and inductive

More information

2014 ELECTRICAL TECHNOLOGY

2014 ELECTRICAL TECHNOLOGY SET - 1 II B. Tech I Semester Regular Examinations, March 2014 ELECTRICAL TECHNOLOGY (Com. to ECE, EIE, BME) Time: 3 hours Max. Marks: 75 Answer any FIVE Questions All Questions carry Equal Marks ~~~~~~~~~~~~~~~~~~~~~~~~~~

More information

Gener. Instructor: Center

Gener. Instructor: Center PDHonline Course E404 (4 PDH) Alternating Current Gener rators and Motors Instructor: Lee Layton, P.E 2013 PDH Online PDH Center 5272 Meadow Estatess Drive Fairfax, VA 22030-6658 Phone & Fax: 703-988-0088

More information

Three-Phase Induction Motor With Frequency Inverter

Three-Phase Induction Motor With Frequency Inverter Objectives Experiment 9 Three-Phase Induction Motor With Frequency Inverter To be familiar with the 3-phase induction motor different configuration. To control the speed of the motor using a frequency

More information

BELT-DRIVEN ALTERNATORS

BELT-DRIVEN ALTERNATORS CHAPTER 13 BELT-DRIVEN ALTERNATORS INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy using the principle of magnetic induction. This principle is based on the

More information

PI Electrical Equipment - Course PI 30.2 MOTORS

PI Electrical Equipment - Course PI 30.2 MOTORS Electrical Equipment - Course PI 30.2 MOTORS OBJECTIVES On completion of this module the student will be able to: 1. Briefly explain, in writing, "shaft rotation" as an interaction of stator and rotor

More information

EXPERIMENT 19. Starting and Synchronizing Synchronous Machines PURPOSE: BRIEFING: To discover the method of starting synchronous motors.

EXPERIMENT 19. Starting and Synchronizing Synchronous Machines PURPOSE: BRIEFING: To discover the method of starting synchronous motors. EXPERIMENT 19 Starting and Synchronizing Synchronous Machines PURPOSE: To discover the method of starting synchronous motors. BRIEFING: When three-phase is applied to the stator of a three-phase motor,

More information

AUCOM WHITE PAPER SERIES GET YOUR MOTOR RUNNING. An introduction to reduced voltage starting of three phase induction motors

AUCOM WHITE PAPER SERIES GET YOUR MOTOR RUNNING. An introduction to reduced voltage starting of three phase induction motors AUCOM WHITE PAPER SERIES GET YOUR MOTOR RUNNING An introduction to reduced voltage starting of three phase induction motors GET YOUR MOTOR RUNNING WHITE PAPER #1 Reduced voltage starting of three phase

More information

694 Electric Machines

694 Electric Machines 694 Electric Machines 9.1 A 4-pole wound-rotor induction motor is used as a frequency changer. The stator is connected to a 50 Hz, 3-phase supply. The load is connected to the rotor slip rings. What are

More information

Electrical Machines-I (EE-241) For S.E (EE)

Electrical Machines-I (EE-241) For S.E (EE) PRACTICAL WORK BOOK For Academic Session 2013 Electrical Machines-I (EE-241) For S.E (EE) Name: Roll Number: Class: Batch: Department : Semester/Term: NED University of Engineer ing & Technology Electrical

More information

DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF MECHANICAL ENGINEERING ME 6351 ELECTRICAL DRIVES AND CONTROL UNIVERSITY QUESTIONS AND ANSWERS

DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF MECHANICAL ENGINEERING ME 6351 ELECTRICAL DRIVES AND CONTROL UNIVERSITY QUESTIONS AND ANSWERS DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF MECHANICAL ENGINEERING ME 6351 ELECTRICAL DRIVES AND CONTROL UNIVERSITY QUESTIONS AND ANSWERS 1) What is the Necessity of starter? UNIT 3 Two Marks Both

More information

MYcsvtu Notes

MYcsvtu Notes D.C. MACHINES 1 INTRODUCTION There are two types of d.c. machines (1) D.C. Generator. (2) D.C.Motor. D.C. MACHINES D.C. Generator D.C. Generator. The d.c. generator converts mechanical energy into electrical

More information

R07 SET - 1

R07 SET - 1 R07 SET - 1 II B. Tech II Semester Supplementary Examinations April/May 2013 ELECTRICAL MACHINES - II (Electrical and Electronics Engineering) Time: 3 hours Max. Marks: 80 Answer any FIVE Questions All

More information

ELECTRIC MACHINES EUROLAB 0.3 kw

ELECTRIC MACHINES EUROLAB 0.3 kw index SINGLE-PHASE MOTORS SPLIT-PHASE MOTOR DL 30130 CAPACITOR MOTOR DL 30140 UNIVERSAL MOTOR DL 30150 REPULSION MOTOR DL 30170 THREE PHASE ASYNCHRONOUS MOTORS SQUIRREL CAGE THREE PHASE ASYNCHRONOUS MOTOR

More information

MAGNETIC EFFECTS OF ELECTRIC CURRENT

MAGNETIC EFFECTS OF ELECTRIC CURRENT MAGNETIC EFFECTS OF ELECTRIC CURRENT It is observed that when a compass is brought near a current carrying conductor the needle of compass gets deflected because of flow of electricity. This shows that

More information

Pretest Module 21 Units 1-3 AC Generators & Three-Phase Motors

Pretest Module 21 Units 1-3 AC Generators & Three-Phase Motors Pretest Module 21 Units 1-3 AC Generators & Three-Phase Motors 1. What are the two main parts of a three-phase 2. Which part of a three-phase squirrel-cage induction motor is a hollow core? 3. What are

More information

UNIT-I ALTERNATORS PART-A

UNIT-I ALTERNATORS PART-A UNIT-I ALTERNATORS 1. What principle is used in Alternators? 2. What are the requirements of an alternator? 3. Mention the types of alternator rotor. 4. What is hunting in alternators? 5. What are the

More information

GROUP OF INSTITUTIONS :: PUTTUR UNIT I SINGLE PHASE TRANSFORMERS

GROUP OF INSTITUTIONS :: PUTTUR UNIT I SINGLE PHASE TRANSFORMERS SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (Descriptive) Subject with Code : Electrical Machines-II (16EE215) Course & Branch: B.Tech EEE Regulation:

More information

MAGNETIC EFFECT OF ELECTRIC CURRENT

MAGNETIC EFFECT OF ELECTRIC CURRENT BAL BHARATI PUBLIC SCHOOL, PITAMPURA Class X MAGNETIC EFFECT OF ELECTRIC CURRENT 1. Magnetic Field due to a Current through a Straight Conductor (a) Nature of magnetic field: The magnetic field lines due

More information

Module 9. DC Machines. Version 2 EE IIT, Kharagpur

Module 9. DC Machines. Version 2 EE IIT, Kharagpur Module 9 DC Machines Lesson 38 D.C Generators Contents 38 D.C Generators (Lesson-38) 4 38.1 Goals of the lesson.. 4 38.2 Generator types & characteristics.... 4 38.2.1 Characteristics of a separately excited

More information

Alternating Current Machines SAMPLE. Learner Workbook. Version 1. Training and Education Support Industry Skills Unit Meadowbank. Product Code: 5633

Alternating Current Machines SAMPLE. Learner Workbook. Version 1. Training and Education Support Industry Skills Unit Meadowbank. Product Code: 5633 Learner Workbook Version 1 Training and Education Support Industry Skills Unit Meadowbank Product Code: 5633 Contents Introduction... 5 Section 1: Operating Principles of Three-Phase Induction Motors.7

More information

Instructor. Payam Zarbakhsh. Department of electrical electronics engineering

Instructor. Payam Zarbakhsh. Department of electrical electronics engineering Instructor Payam Zarbakhsh Department of electrical electronics engineering Electrical Machines Induction Motors_Note(1) Comparing with synchronous motor No dc field current is required to run the machine.

More information

(d) The magnetic field lines, produced around a straight current-carrying conductor, are concentric circles. Their centres lie on the wire.

(d) The magnetic field lines, produced around a straight current-carrying conductor, are concentric circles. Their centres lie on the wire. Page 240»Exercise» Question 1: Which of the following correctly describes the magnetic field near a long straight wire? (a) The field consists of straight lines perpendicular to the wire (b) The field

More information

EFFECT OF CAPACITOR ON STARTING & RUNNING OF SINGLE PHASE INDUCTION MOTOR

EFFECT OF CAPACITOR ON STARTING & RUNNING OF SINGLE PHASE INDUCTION MOTOR INDEX NO. : M-145 TECHNICAL MANUAL FOR EFFECT OF CAPACITOR ON STARTING & RUNNING OF SINGLE PHASE INDUCTION MOTOR Manufactured by : PREMIER TRADING CORPORATION 212/1, Mansarover Civil Lines, MEERUT. Phone

More information

EXPERIMENT 2 THREE PHASE INDUCTION MOTOR, PART 1

EXPERIMENT 2 THREE PHASE INDUCTION MOTOR, PART 1 University f Jordan School of Engineering Department of Mechatronics Engineering Electrical Machines Lab Eng. Osama Fuad Eng. Nazmi Ashour EXPERIMENT 2 THREE PHASE INDUCTION MOTOR, PART 1 OBJECTIVES To

More information

SYLLABUS 1. SYNCHRONOUS GENERATOR 9 2. SYNCHRONOUS MOTOR 8

SYLLABUS 1. SYNCHRONOUS GENERATOR 9 2. SYNCHRONOUS MOTOR 8 SYLLABUS 1. SYNCHRONOUS GENERATOR 9 Constructional details Types of rotors emf equation Synchronous reactance Armature reaction Voltage regulation EMF, MMF, ZPF and A.S.A methods Synchronizing and parallel

More information

Unit-I MEASURING INSTRUMENTS

Unit-I MEASURING INSTRUMENTS Unit-I MEASURING INSTRUMENTS 1.1 Definition of instruments: An instrument is a device in which we can determine the magnitude or value of the quantity to be measured. The measuring quantity can be voltage,

More information

DC Generator. - The direction of current flow in the conductor is given by Fleming s right hand rule. Figure 2: Change in current direction

DC Generator. - The direction of current flow in the conductor is given by Fleming s right hand rule. Figure 2: Change in current direction DC Generator 1. THE DIRECTION OF CURRENT DUE TO INDUCED VOLTAGE: UNDERSTANDING FLEMING S RIGHT HAND RULE - The direction of current flow in the conductor is given by Fleming s right hand rule Figure 1:

More information

EXPERIMENT CALIBRATION OF 1PHASE ENERGY METER

EXPERIMENT CALIBRATION OF 1PHASE ENERGY METER EXPERIMENT CALIBRATION OF PHASE ENERGY METER THEORY:- Energy Meters are integrating instruments used to measure the quantity of electrical energy supplied to a circuit in a given time. Single phase energy

More information