Ac Machines-i Ls.pdf

BALAJI INSTITUTE OF TECHNOLOGY & SCIENCE Laknepally, Narsampet, Warangal - 506 331

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING LECTURE SCHEDULE

NAME OF FACULTY : M.SREELEKHA SUB: AC MACHINES-I

AY : 2017 - 2018 DEEE IV Sem

Lecture Number

Topic Covered Date

NAME OF THE TOPIC

UNIT-I (SINGLE PHASE TRANSFORMERS) 1

Introduction

2

Working Principle of a transformer

3

HV and LV Windings

4

Transformer on DC Supply

5

Transformer Classification

6

Construction of Transformer

7

Types of Transformers- based on construction

8

Comparision between Core type and shell type Transformers

9

Ideal Transformer

10

EMF Equation of a Transformer

11

Voltage and Current transformation Ratios

12

Transformer on NO-Load

13,14,15 Transformer ON-Load Practical Transformer Analysis 16 17,18

Practical Transformer on load considering winding resistance and leakage reactance

19

Equivalent circuit of a Transformer

20

Voltage Regulation of a Transformer

21

Losses in a Transformer

22

Efficiency of a Transformer

22,23 24 25,26

Open Circuit and Short Circuit Tests Necessity of Transformer rating is in KVA Difference between Ideal and Practical Transformer

27

All-Day Efficiency

28

Difference between distribution and Power Transformer

29,30

Polarity test on Transformer

31,32

Sumpner's Test

33,34

Paralle Operation of Transformers

35

Numerical Problems UNIT-II (THREE PHASE TRANSFORMERS)

36

Introduction

36

3-Phase Transformers Vs three 1-Phase transformer bank

37

3-Phase Transformer Connections

37

Voltage and Current Relationships for 3-Phase Transformer Connections

38

Open-Delta Connections

38

Parallel Operation of 3-Phase Transformers

39

Special Transformers

40

Auto-Transformers

41

Scott- Connection

42

Cooling of Transformers

43

Transformer Tank and accessories

44

Tap Changers

45

Humming of Transformers UNIT-III (ALTERNATORS)

46 47,48

Introduction Construction details of Alternators

49

Stator and Rotor

50

Types of Rotors

51

Exciters

52

Working Principle of an Alternator

53

Parts of Alternator with Material used

54

Frequency of Induced EMF

55

Synchronous Speed

56

Advantages of stationary Armature or Advantages of rotating Field system

57 58 59 60 61 62 63 64 65 66 67, 68

Armature Windings Classification of Armature windings Single phase and Poly phase windings Single layer and Double layer windings Lap,Wave and Concentric (or)Spiral winding Full pitch and Short Pitch Coils Concentrated and Distributed Winding Winding Factors EMF Equation of an Alternator Alternator on Load (Voltage Variations on Load) Synchronous Reactance and Synchronous Impedance Factors that cause a change of Alternator Terminal Voltage on Load Vector Diagrams of a loaded Alternator Voltage Regulation by Synchronous Impedance Method No-Load induced emf for different power Factors Numerical Problems UNIT-IV (PARALLEL OPERATION OF ALTERNATORS) Synchronising of Alternators

Necessity of Parallel operation(or)Advantages of Parallel Operation 69,70 Conditions for Synchronisation

71 72 73,74 75

Synchronising of Alternators 1-Phase Alternators by Lamp Method 3- Phase Alternators Load sharing between two Alternators

Sign of Faculty

Sign of HoD