This document provides information about the BE8255 – Basic Electrical Electronics and Measurement Engineering course at JNN Institute of Engineering. It outlines the course objectives, which include explaining basic theorems in electrical circuits, components and functions of electrical machines, fundamentals of semiconductors and applications, principles of digital electronics, and imparting knowledge of communication. It lists the textbook and references for the course and provides details about the topics that will be covered, including DC and AC rotating machines, electrical machines, single phase induction motors, and transformers.

1. JNN INSTITUTE OF
ENGINEERING
BE8255 – BASIC ELECTRICAL ELECTRONICS AND
MEASUREMENT ENGINEERING
MALATHY N, ASSISTANT PROFESSOR
Department of EEE

2.  To explain the basic theorems used in Electrical circuits and
the different components and function of electrical
machines.
 To explain the fundamentals of semiconductor and
applications.
 To explain the principles of digital electronics
 To impart knowledge of communication.
OBJECTIVES

3. At the end of the course, the students will able to
 Define the fundamental laws, theorems of electrical circuits
and principles and operation of measuring instruments.
 Summarize the basic principles of electrical machines and
their performance
 Utilize the different energy sources, protective devices and
their field applications
 Design the fundamentals of electronic circuit constructions.
 Explain the fundamentals of communication engineering.
COURSE OUTCOMES

4. TEXT BOOKS:
1. D P Kothari and I.J Nagarath, ”Electrical Machines “Basic Electrical and
Electronics Engineering”, McGraw Hill Education(India) Private Limited,
Third Reprint ,2016
2. S.K.Bhattacharya “Basic Electrical and Electronics Engineering”, Pearson
India, 2011
3. Sedha R.S., “Applied Electronics”, S. Chand & Co., 2006
REFERENCES
1. A.E.Fitzgerald, David E Higginbotham and Arvin Grabel, “Basic Electrical
Engineering”, McGraw Hill Education(India) Private Limited, 2009
2. Del Toro, “Electrical Engineering Fundamentals”, Pearson Education, New
Delhi, 2007
3. Leonard S Bobrow, “ Foundations of Electrical Engineering”, Oxford
University Press, 2013
4. Mahmood Nahvi and Joseph A. Edminister, “Electric Circuits”, Schaum’
Outline Series, McGraw Hill, 2002.
5. Mehta V K, “Principles of Electronics”, S.Chand & Company Ltd, 1994.
6. Nagsarkar T K and Sukhija M S, “Basics of Electrical Engineering”, Oxford
press 2005.

5.  DC and AC ROTATING MACHINES: Types, Construction,
principle, Emf and torque equation, application Speed
Control- Basics of Stepper Motor – Brushless DC motors-
Transformers-Introduction- types and construction, working
principle of Ideal transformer-Emf equation- All day
efficiency calculation.
 https://www.youtube.com/watch?v=IC-PWxtcirI
 https://www.youtube.com/watch?v=CWulQ1ZSE3c
UNIT II ELECTRICAL MACHINES

6.  A dc generator is a machine that converts mechanical
energy into electrical energy (dc voltage and current) by
using the principle of magnetic induction.
DC GENERATOR
1.Yoke or Magnetic frame
2. Pole core and pole
shoes
3. Field winding
4.Armature-Armature
core, Armature winding.
5. Commutator
6. Brushes

8.  Yoke:
outer frame of a dc machine
 Pole core, pole shoes:

9.  Inter poles:
– Inter poles or the commutating poles
– To improve commutation.
 Field winding:
– The field winding is placed on the pole core.
– To carry the current and to produce the magnetic flux.

10.  Armature:
– Armature core
– Armature winding
 Armature core:
– cylindrical in shape with slots
– It is mounted on the shaft.
 Armature winding:

11.  COMMUTATOR
BRUSHES

12.  Faradays laws of electromagnetic induction
 It states that whenever the magnetic lines of force i.e., flux
linking with a conductor or a coil changes, an emf is induced
in that conductor or coil.
 https://www.youtube.com/watch?v=mq2zjmS8UMI
Working of DC Generator:

13. Working of DC Generator:

14.  ϕ= Flux/pole in weber.
 N=Speed of armature in RPM
 P=Number of poles
 N/60=Speed of armature in RPS
 Z= Total number of armature conductors.
 E = EMF induced in any parallel path in the armature in
volts
 A=Number of parallel paths
According to Faraday’s law, the induced emf is proportional
to the rate of change of the magnetic flux.
i.e ., e =-dϕ/dt
EMF equation of dc generator

15. Let us consider a single conductor moving during one
revolution.
dϕ=ϕ*P weber
Number of revolutions per second, =N/60 seconds.
Time taken to complete one revolution, dt=60/N seconds.
According to Faraday’s laws of electromagnetic induction.
EMF generated/conductor = dϕ/dt
……………….(1)

16. Substituting, dϕ=ϕ*p and dt=60/N in equation (1) gives
=ϕ*p/(60/N)
EMF generated/conductor =ϕNp/60 volts
Number of conductors in one path of armature =z/A
EMF generated/path = (ϕpN/60) *(z/A) volts
For wave winding, A=2
EMF generated/path = (ϕpN/60) *(z/2) volts
=ϕpNz/120 volts
For lap winding, A=P
EMF generated/path = (ϕpN/60) *(z/P) volts = ϕNz/60 volts

17.  Separately excited DC generator.
 Self excited DC generator
- DC shunt generator
- DC series generator
- DC compound generator
Types of DC generators

18.  A dc generator whose field winding is energized from an
independent external dc source is called separately excited
dc generator.
 Armature current Ia=IL
 Generated emf Eg=V+ Ia Ra+ VBrush
 Power developed in the armature = Eg Ia
 Power delivered to load=V Ia
Separately excited DC generator

19.  Self-excited DC Generator is a device, in which the current
to the field winding is supplied by the generator itself
A shunt DC generator
 Field winding is connected in parallel with armature.
 It is a “constant speed” machine.
 Shunt field current Ish=V/Rsh
 Armature current Ia = IL+ Ish
 Generated emf, Eg=V+ Ia Ra+ VBrush
Ia Ra=Voltage drop in the armature resistance
VBrush = Voltage drop at connects of the brush
Self excited DC generator

20.  The field winding is connected in series with armature.
 Same current flows through field as armature.
 Ia=IL=Ise
 Generated emf Eg=V+ Ia Ra +Ia Rse + VBrush
 Ia Rse= Voltage drop in the series field winding resistance
series DC generator

21. Short shunt
 Load current IL=Ise
 Shunt field current Ish=(V+IseRse)/Rsh
 Generated emf Eg=V+ Ia Ra+Ise Rse+ Vbrush
Long shunt
 Series field current Isc =Ia=IL+ Ish
 Shunt field current Ish=V/Rsh
 Generated emf Eg=V+Ia(Ra+Rse)+VBrush
A compound generator

22.  electrical energy into mechanical energy
 Principle of operation
 “Whenever current carrying conductor is placed in magnetic
field, the conductor experiences a force tending to move
it”. The force whose direction is given by Fleming’s Left-
Hand Rule and whose magnitude is given by
F=BILNewton.
B=Magnetic field intensity in wb/m2
I=Current in Amperes
L=Length of the conductor in meter.
DC MOTOR

23. Principle of operation

24.  Back emf of a Motor:
Eb=(ϕ Z N/60)*(p/A)

25. DC Shunt Motor
 Shunt field current Ish=V/Rsh
 Armature current Ia = IL- Ish
 Supply voltage V= Eb +IaRa+ VBrush
 Ia Ra=Voltage drop in the armature resistance
 VBrush = Voltage drop at connects of the brush
 Input current IL=PL/V
Types of DC motors

26.  Ia=IL=Ise
 V= Eb+Ia Ra +Ia Rse +VBrush
 Ia Rse= Voltage drop in the series field winding resistance
 IL=PL/V
DC Series Motor

27. Long Shunt
 Series field current Ise =Ia=IL- Ish (or) IL=Ia+Ish
 Shunt field current Ish=V/Rsh
 V = Eb + IaRa+IaRse + VBrush
Compound Motor

28.  Load current IL=Ise
 Shunt field current Ish=(V-IseRse)/Rsh
 V=Eb+ Ia Ra+Ise Rse+VBrush
Short Shunt

29. EMF EQUATION OF DC GENERATOR

30. P=4, ᵠ= 0.02wb, N=1500 rpm, A=2 (wave wound)
Z= No. of conductors per slot X No of slots
= 12 X 65 = 780
Eg = 780 V
Problem: Calculate the emf generated by 4 pole wave wound generator
having 65 slots with 12 conductors per slop when driven as 1500 rpm. The
flux per pole is 0.02 wb

31. 1) 4 pole wave wound armature has 720 conductor and is related
1000 rev/min. If the useful flux is 20 mWb, calculated the
generated voltage.
Ans - 480v
2) An 8 pole lap connected has armature 4 slot with 12 conductor an
generate of voltage 500v determine the speed at which running if
the flux per pole is 50 mWb.
Ans - N = 1250 r.p.m
3) A DC generator has an armature EMF of 100v when the useful flux
per pole is 20mWb adding the speed of 800 RPM calculate the
EMF generator (a) which the same flux and speed of 1000 r.p.m
(b) with a flux per pole 24mWb and the speed of 900 r.p.m.
Ans - a. 125V
b. 135V
Problems to Solve

32. 4) An 8-pole lap-wound d.c. generator armature has 960,
conductors, a fian 40 mWb and a speed of 400 r.p.m.
Calculate the e.m.f generated on open circuit the same
armature is wave wound, at what speed must the
armature be driven to generate 400v.
Ans - 256v
15625 r.p.m
5) A 6-pole d.c generator runs at 850 r.p.m. and each pole has
a flux of 12 mWb. there are 150 conductors in series
between each pair of brushes, What us the value of
generated e.m.f. ?
Ans - 153v
Problems to Solve

33.  two-pole or four-pole, 2 hp or less
 domestic appliances
 resembles, three-phase, squirrel-cage motor
 no starting torque & special arrangement
Types of Single-Phase Motors
 (i) split-phase type
 (ii) capacitor start type
 (iii) capacitor run type
 (iv) capacitor start capacitor run type
 (v) shaded-pole type
 Three phase IM
 https://www.youtube.com/watch?v=AQqyGNOP_3o
SINGLE PHASE INDUCTION MOTOR

34.  https://www.youtube.com/watch?v=awrUxv7B-a8
 https://www.youtube.com/watch?v=mQ-gPMDv-tI
 not self starting
 double-field revolving theory.
 https://www.youtube.com/watch?v=DNo47MW-H4s
Working

35.  Stator
 Rotor
Stator
 laminated iron core with two windings
 main winding and a starting (also known as an auxiliary) winding
 windings are displaced by 90°
 main winding - very low resistance and high inductive reactance.
 Auxiliary winding – very high resistance and low inductive
reactance
Construction of single phase induction motor

37.  resistance-start motor
 high starting current
 starting torque is about
1.5 times full-load torque
 washing machines.
 Air conditioning fans.
 food mixers, grinders, floor polishers,
 blowers, centrifugal pumps,
 small drills, lathes, office machinery, etc.
Split-phase Type

38. CAPACITOR START TYPE

39. CAPACITOR-START CAPACITOR-RUN
MOTORS

40. SHADED POLE INDUCTION MOTOR

41. SHADED POLE IM

43.  runs at synchronous speed.
 rotor that has a set of salient poles excited by direct current
to form alternate N and S poles.
 Ns = 120f / P
SYNCHRONOUS MOTOR

45.  electromechanical device
 The motor’s position can be controlled accurately without
any feedback mechanism, as long as the motor is carefully
sized to the application
 Permanent magnet stepper
 Hybrid synchronous stepper
 Variable reluctance stepper
 https://www.youtube.com/watch?v=eyqwLiowZiU
STEPPER MOTOR

46. Variable Reluctance Stepper Motor

47. Permanent magnet stepper

48.  Similarities to AC induction motors and brushed DC motors.
 Hall sensor provides the information to synchronize stator
armature excitation with rotor position
 The electronic controller circuit energizes appropriate motor
winding by turning transistor or other solid state switches to
rotate the motor continuously.
 no mechanical commutator
 High speed of operation
 Computer hard drives and DVD/CD players
 Electric vehicles, hybrid vehicles, and electric bicycles
 https://www.youtube.com/watch?v=bCEiOnuODac
BRUSHLESS DC MOTOR

49.  static device
 principle of mutual induction between two inductively coupled
coils.
 Iron core to provide a low reluctance path
 https://www.youtube.com/watch?v=U3CubKnkO4c
TRANSFORMER

50. TRANSFORMER
https://www.youtube.com/watch?v=Cx4_7lIjoBA&t=423s

51.  N1 = Number of turns in primary winding
N2 = Number of turns in secondary winding
Φm = Maximum flux in the core (in Wb) = (Bm x A)
f = frequency of the AC supply (in Hz)
 average rate of change of flux = Φ
m /(T/4) = Φ
m/(1/4f)
average rate of change of flux = 4f Φm
 Induced emf per turn = rate of change of flux per turn
 average emf per turn = 4f Φm
 Form factor = RMS value / average
EMF Equation Of The Transformer

52. RMS value of emf per turn = Form factor X average emf per turn
RMS value of emf per turn = 1.11 x 4f Φm = 4.44f Φm
RMS value of induced emf in whole primary winding (E1) = RMS
value of emf per turn X Number of turns in primary winding
E1 = 4.44f N1 Φm
RMS induced emf in secondary winding (E2)
E2 = 4.44f N2 Φm
voltage transformation ratio
If N2 > N1, i.e. K > 1, then the transformer is called step-up transformer.
If N2 < N1, i.e. K < 1, then the transformer is called step-down transformer.
EMF Equation Of The Transformer

53. All Day Efficiency of a Transformer
https://www.youtube.com/watch?v=Yn0BGv_EACo