Page 102 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

Step –up chopper is also known as Boost choppers. Applications of the step up choppers include battery charging
and as a voltage booster.

Applications of Chopper :
DC to DC converters are applied for many applications such as in
Switched Mode Power Supply System.
in DC motors as speed controllers.

DC voltage boosters.
Battery chargers.
Railway systems.
Electric cars etc…
Choppers are used in signal processing systems also. In choppers, the output voltage can be controlled using
many different techniques such as Pulse width modulation, Frequency modulation, Variable frequency, variable
pulse width, CLC control, etc.

INVERTER
In India and other countries, the main system of electric supply is single and three-phase AC supply but sometimes
shutdown or failure of electric supply may occur so an alternative system is become very much necessary at that
particular time. This type of alternative system is called emergency electric supply system.
Generators are the best example of this system but it is very much expensive due to high price of its fuel and its
smoke is very harmful for environment as well as human health. So due to this, there is a need generated for such
systems which are free from these lacks. Hence, the development of inverter and uninterrupted power supply
have given us a silent and almost pollution free system of emergency supply.

In inverter, 12V/24V battery supply (DC supply) is converted into 230 V, 50 Hz AC supply. A battery charging circuit
is also incorporated in the inverter to recharge the battery many times, when needed. In order to emergency
power supply, there is one more power system which is very much used by computer system, is Uninterrupted
Power Supply (UPS).
Because as interruption of even millisecond can cause a loss of data, damage to hardware as well as software
and interruption of works. So all these things increase the financial loss. A UPS provides at least 10-15 min
backup time in case of desktop PC and 1 to 2 hours in case of laptops Therefore, the study of inverter and UPS
and their installation becomes necessary for an electronic mechanic.
An inverter is used to produce an uninterrupted 220 V or 110 V AC (depending on the line voltage of a particular
country) supply to the device connected as the load at the output socket.

The inverter gives constant AC voltage at its output socket when the AC mains power supply is not available.
Working of Inverter
The working of an inverter can be considered in the following conditions.

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CITS : E & H - Electronics Mechanic - Lesson 48 - 55