1. PROJECT
ON
REGULATED POWER SUPPLY
BASAVESHWAR ENGINEERING COLLEGE
(AUTONOMOUS), BAGALKOT
DEPARTMENT OF ELECTRONICS AND
COMMUNICATION ENGINEERING
Guided by :
Prof. M. C. Aralimarad
(Professor, Department of ECE)
Basaveshwar Engineering College, Bagalkot
2. INDEX
1. Introduction to Power supply
2. Block Diagram of Power supply
3. Explanation for Power supply
4. Circuit diagram of Power supply
5. Working of Power supply
6. Advantages and Disadvantages of power
supply
7. Applications of power supply
3. INTRODUCTION
• Definition: A regulated power supply system
takes the unregulated alternating or ac power
and provides a regulated unidirectional or dc
power supply
• The main objective to design a regulated to is
get always a constant voltage even when the
input supply voltage or connencted load
changes
• So, this is involved in voltage step down,
rectification, filtration, and regulation
4. OBJECTIVES
• A regulated power supply converts un regulated
AC into a constant DC.
• Regulated power supply is used to ensure that the
output remains constant even if the input
changes.
7. The most important blocks of this system
1. Transformer
2. Rectifier
3. Filter
4. Regulator
8. 1)TRANSFORMER
• The transformer is a device that transfers the electerical energy
form one circuit to another circuit by changing voltage level.
• Here, in this, step down transformer is used that is used to step
down the voltage .
• Generally it takes the 220V supply as input and provides 9V or
12V or 24V as the output according to the circuit output
requirement. By changing the turns ratio of the transformer, the
output voltage can be changed
• The transformer is not essential part of a regulated power supply
circuit ,It is only used when voltage steps down required.
• If the output requires 230V directly there is a no need for
transformer
10. TYPES OF TRANSFORMER
• Based on Voltage Levels
i. Step-up transformer: They are used
between the power generator and the
power grid.The secondary output voltage is
higher than the input voltage.
ii. Step-down transformer: They are used
between the power generator and the
power grid.The secondary output voltage is
lesser than the input voltage.
11. 2) RECTIFIER
• The rectifier is an electrical or electronic circuit made of pn-
junction diodes.
• The main function of the rectifier circuit is to convert the AC
supply into a DC supply.
• It takes the alternating current as a input and gives the direct
current as output.rectifier is a second block of power supply.
• Both half and full-wave rectifier circuits can be used.
• The half wave rectifier circuit rectifies one-half cycle only and
makes more power loss but the full-wave rectifier circuit rectifies
both half cycles and makes very low power loss.
• For, this reason center tap full wave rectifier or bridge rectifier
cricuit is used
13. TYPES OF RECTIFIERS
I. Half-wave rectifiers: half-wave rectifier transform AC voltage to DC
voltage. Half wave rectifier defines as a type of rectifier that allows
only one half cycle of an a AC voltage waveform to pass while
blocking the other half cycle
II. Full-wave rectifiers: A rectifiers that converts alternating current
into direct current and that utilize the halves of each cycle of the
alternating current.
III. Full-wave bridge rectifiers: the diode bridge rectifier circuit of 4
diodes that is used in the process of converting alternating current
from the input terminals to the direct current on the output
terminals.
IV. Voltage multipliers rectifiers: voltage multiplier is a type of diode
rectifier circuit which can produce an output voltage many times
greater than of the applied input voltage
14. 3) FILTER
• The filter circuit is a circuit which removes the AC component from
the output of the rectifier and produces the pure DC output across
the load.
• The output of the rectifier circuit cannot provide the pure DC
supply.
• There are some ripple or AC components available in the DC power
supply.
• To remove those ripples or make the DC power supply pure, a filter
circuit is used.
• The output of the rectifier is connected to the input of the filter
supply.
• Generally a pure capacitor filter, LC filter are used. According to
nature, a capacitor block DC and allows AC, so it can be connected
in parallel for the filteration.
16. TYPES OF FILTERS
1. Capacitor filter :Used to obtain essentially a
DC voltage with some ripple
2. RC Filter : It is possible to reduce the amount
of ripple across a filter capacitor by using an
additional RC filter
3. LC Filter : This reduces Hum & ripple (used
where noise should be reduced)
17. 4) REGULATOR
• It is the last block of the regulated power supply.
• The regulator power supply is one that maintains
constant output voltage or current despite
variations in load current or input voltage
• The regulator actually does the regulation the
regulator circuit uses different types of regulating
components and devices such as zener diode, IC
78XX series, IC 317, etc.
• It always provides a 5V DC voltage as its output
20. ADVANTAGES OF RPS
1. Simplicity of design
2. Reliability
3. Low noise levels
4. Low cost
5. Space savings
6. Fast transient response
7. Low thermal dissipation
21. DISADVANTAGES OF RPS
1. Low efficiency if input and output difference is
large.
2. May require a heat sink.
3. Capable of exclusively of step down operation.
4. Capable exclusively of step down operation.
5. High input ripple current.
22. APPLICATIONS OF RPS
1. Mobile phone charger
2. Various oscillators
3. These are used in amplifiers
4. Electronic computers
5. Automatic control systems and equipment
6. It can be also used as stabilized current power
supply for the verification of some electrical
instruments
23. CONCLUSION
Regulated power supplies maintain the voltage at
the desired level and are ideal for almost all types
of electronic devices because of smooth, steady
supply of voltage they offer.
From the above information, finally, we can
conclude that an RPS changes unregulated
alternating current to a stable direct current. A
regulated DC power supply is also named as a
linear power supply
