Here are the solutions to the transformer problems: 1. A transformer has 100 turns on coil 1 and 200 turns on coil 2. i. If the voltage on coil 1 is 10 volts, the voltage on coil 2 will be 20 volts (Voltage on coil 2 = Voltage on coil 1 x Turns on coil 2/Turns on coil 1 = 10V x 200/100 = 20V) ii. If the voltage on coil 1 is 200 volts, the voltage on coil 2 will be 400 volts (Voltage on coil 2 = Voltage on coil 1 x Turns on coil 2/Turns on coil 1 = 200V x 200/100 = 400V) iii.

2. Contents:

3. History first
A varying current in the
or primary winding creates a
varying magnetic flux in the
transformer's core and thus a
varying magnetic field through
the secondary winding.

4. History
This varying magnetic
field induces a
varying electromotive force
(EMF), or "voltage", in the
secondary winding. This effect
is called inductive coupling.

5.  A transformer is a device
that transfers electrical
energy from one circuit to
another through
inductively coupled
conductors—the
transformer's coils.

6. How it is used?
 A transformer is used to
bring voltage up or down
in an AC electrical circuit.
A transformer can be
used to convert AC power
to DC power.

8. Responsible
for the
Development
of
TRANSFORMER

9. William Stanley, Jr. (USA)
•He contributed
to the
development of
an alternating
current
induction
motor.

10. Lucien Gaulard (France)
(1850 - November
26, 1888)
invented devices
for
the transmission
of alternating
current electrical
energy.

11. Sebastian Ziani de Ferranti
(England)
who promoted the
installation of
large electrical
generating
stations and
alternating-current
distribution
networks in

12. TRANSFORMER
Power converter
that transfer
electrical energy
from one circuit to
another through
inductively.

13. Principle
 transformer is based on two
principles:
 (1) that an electric current can
produce a magnetic field (
electromagnetism)
 (2) that a changing magnetic field
within a coil of coil induces a
voltage across the ends of the coil
( electromagnetic induction)

14. TYPES OF TRANSFORMER
Step Up Transformer
Step Down Transformer

15. Step Up Transformer
This type of
transformer
converts low
voltage of high
voltage at low
current.

16. Primary
The primary coil
is made of thick
copper wire while
the secondary coil
is made of thin
wire.

17. Secondary
The number of
turns in the
secondary coil is
greater than the
number of turns in
the primary coil.

18. Step Down Transformer
If we assume
there is no loss
of power,
Out put power
= Input power
EsIs = EpIp = K

19. If a load is connected to the secondary
winding, current will flow in this winding, and
electrical energy will be transferred from the
primary circuit through the transformer to the
load. In an ideal transformer, the induced
voltage in the secondary winding (Vs) is in
proportion to the primary voltage (Vp) and is
given by the ratio of the number of turns in the
secondary (Ns) to the number of turns in the
primary (Np) as follows:

20. The transformer equation:
N1 = V1
N2 = V1
N1 = Number of turns on coil 1
N2 = Number of turns on coil 2
V1 = Voltage on coil 1
V2 = Voltage on coil 2

21. Advantage of Alternative
Current
 Electric power distribution
primarily used direct current at
the same voltage used by motors
and lights.
 Changing direct current voltage
level required rotating machinery
which was costly to purchased
and install.

22. Advantage of Alternative
Current

23. BASIC TRANSFORMER
 The basic transformer is an
electrical device that transfers
alternating-current energy
from one circuit to another
circuit by magnetic coupling of
the primary and secondary
windings of the transformer.

24. The voltage applied to the primary winding causes current
to flow in the primary.
This current generates a magnetic field, generating a
counter emf (cemf) which has the opposite phase to that of
the applied voltage. The magnetic field generated by the
current in the primary also cuts the secondary winding and
induces a voltage in this winding.

25. TRANSFORMER
CONSTRUCTION
 A TRANSFORMER consists
of two coils of insulated
wire wound on a core. The
primary winding is usually
wound onto a form, then
wrapped with an insulating
material such as paper or
cloth.

26. TRANSFORMER
CONSTRUCTION

27. Transformer Consructions
 The most common types of
transformers are the shell-core
and the hollow-core types. The
type and shape of the core is
dependent on the intended use
of the transformer and the
voltage applied to the current in
the primary winding.

28. Exciting Current
 When voltage is
applied to the primary
of a
transformer, exciting
current flows in the
primary.

29. The current causes a magnetic field
to be set up around both the
primary and the secondary
windings. The moving flux causes a
voltage to be induced into the
secondary winding, countering the
effects of the counter emf in the
primary.

30. Power of
Transformer
 A transformer with two or
more windings wound on a
laminated iron core. The
transformer is used to supply
stepped up and stepped down
values of voltage to the
various circuits in electrical
equipment.

31. Power of Transformer

32. Application
 The major application of
transformer is to increase
voltage before transmitting
electrical energy over long
distances through the wire.
 Also used extensively in
electronic products to step
down the supply voltage to a
level suitable for the low
voltage circuits they contain.

33. Activity Time

34. Question…..

35. If this is a step–up
transformer, which
side would be the
secondary?
A. Right
B. Left

36. Correct Answer
Is (b.) Left
A step-up transformer raises
voltage.The secondary would
have more voltage and
more coils: the left side.

37. Which side has the
most CURRENT?
A. Bottom
B.Top

38. A. Bottom because
Power in must =
Power out, the side
with the least voltage
must have the most
current.

39. currentmust be use
in transformer??
A. Ac
B. Dc

40. Answer : A. AC A
transformer transfers
voltage by transferring
magnetic flux. Magnetic flux
occurs with changing
magnetism and changing
current: Alternating
Current.

41. Problem Solving
1.A transformer has 100 turns on
coil 1 and 200 turns on coil 2.
*What will the voltage on coil 2 be
if the voltage on coil 1 is
i. 10 volts?
ii. 200 volts?
iii. 1000 volts?

44. Created By:
Mallillin, Khate A.
• IV-2
•
Fernandez, Mariel
• IV-2
•
Aguilar, Marry Grace
• IV-2
•

45. References:
• http://www.physicstutorial
s.org/home/magnetism/tr
ansformers
• http://www.worsleyschool.
net/science/files/transform
ers/page.html
• http://www.tpub.com/neet
s/book2/5k.htm
• *http://edisontechcenter.o
rg/Transformers.html