PROJECT ON
FULL WAVE RECTIFIER
INDEX
1. CERTIFICATE
2. ACKNOWLEDGMENT
3. INTRODUCTION
4. AIM
5. MATERIALS REQUIRED
6. PROCEDURE
7. WORKING
8. EFFICIENCY
9. BIBLIOGRAPHY
INTRODUCTION
A rectifier is an electrical device that converts alternating
current (AC), which periodically changes direction, to
direct current (DC), which flows in only one direction.
The process is known as rectification. Rectification
produces a type of DC that encompasses active voltages
and currents, which are then adjusted into a type of
constant voltage DC, although this varies depending on
the current's end-use. The current is allowed to flow
uninterrupted in one direction, and no current is allowed
to flow in the opposite direction. Physically, rectifiers
take a number of forms, including vacuum tube diodes,
mercury-arc valves, copper and selenium oxide rectifiers,
semiconductor diodes, silicon-controlled rectifiers and
other silicon-based semiconductor switches. Rectifier
circuits may be single-phase or multi-phase. Most low
power rectifiers for domestic equipment are singlephase, but three-phase rectification is very important for
industrial applications and for the transmission of energy
as direct current (DC).
AIM
To construct a Full Wave rectifier and show that the
alternating current (AC) is rectified into direct current
(DC).
MATERIALS REQUIRED
1. Connecting Wires
2. A plug
3. Single Lead Wire- 2m
4. Cardboard
5. Capacitor
6. A Transformer (6V)
7. A Resistor
8. P-N Junction Diode
9. A LED
10. Insulation Tape, Blades, Soldering Wax, Soldering
Lead, Soldering Iron & Sand Paper
PROCEDURE
Connections are done as in the circuit. The A.C. supply is
given to both the input wires of the transformer and the
two ends of the secondary coil is given to the P side of
the two diodes and the N side of the diodes are twined
and then connected to one end of the capacitor and the
other end to the center tap lead and to the resistor.
Further, the other end of capacitor with the diode
connection is connected to the other end of the resistor.
Connect 2 leads on both the ends of the resistor to
measure the output and this is connected to the positive
and negative terminals of the bulb.
WORKING
First when the A.C. is supplied to the transformer, it
steps down the 220V main supply to 6 volts. It has a
capability of delivering a current of 500mA. The 6 volts
A.C. appearing across the secondary is the RMS value and
the peak value is 8.4 volts. During the first half cycle of
the A.C. input Diode D1 is forward biased and a current ‘I’
flows in the circuit in the direction S1D1ABEOS1. During
this time diode D2 is reverse biased. So it does not
conduct any electric current. During the next half cycle
the diode D2 is forward and D1 is reversed. Hence D2
conducts current in the direction S2D2ABEOS2 and D1
does not conduct any current. In subsequent half cycles
of the A.C current the above processes are repeated. In
both the half cycles it is clear that current flows through
the resistor in only one direction ABE. Even though the
voltage across RL is unidirectional it will still contain a
few A.C components. This is filtered and made
Smooth using a capacitor, which filters 99% of the A.C
current. A resistor is then used to adjust the output
voltage. Capacitor also nearly filters all A.C components
from the supply and resistance is adjusted for the
required output. As this is a simple circuit, only one
capacitor and a resistance are being used. But there will
be slight factor of alternating current (AC) still left in the
output but it is negligible. The output Direct Current and
voltage light up the LED.
EFFICIENCY
An efficiency of full wave rectifier is defined as the ratio
of DC power output to the input AC power. Therefore,
Efficiency = DC power output / AC power input
= 0.812 RL / (rf + RL)
If rf is neglected as compared to RL ,the efficiency of the
rectifier is maximum given as;
ηmax = 0.812 = 81.2%
BIBLIOGRAPHY
1. www.google.com
2. www.wikipedia.com
3. www.physicstoday.com
4. www.scribd.com
5. www.icbse.com
THANK
YOU