Download Purpose Buck-Boost Chopper Type AC Voltage Controller

BUCK-BOOST CHOPPER TYPE AC
VOLTAGE CONTROLLER
Presented By:
K. Bhagya Lakshmi,
ME(PED).




AC voltage regulation is an important part of power
conversion.
A winding transformer is widely used in voltage regulation
fields such as power system, motor speed control and so on.
There are also other researches which use thyristor phase
controlled circuit to do voltage regulation.But they have some
disadvantages and those arise problems.
These problems can be solved by using high switching
frequency AC chopper i.e. Buck-Boost chopper type AC
voltage controller.



This device is used to increase or decrease the voltage
levels according to requirement.
Best speed control is possible with this controller as it
has fast response speed.
To decrease the losses at conversion devices in ACAC systems it’ll well suitable i.e. transformer has
iron losses which effects on its efficiency.


There are two devices, can perform the AC Voltage
regulation:
1. Transformer
2. Phase Controlled Thyristor circuit
These devices has certain disadvantages and these
disadvantages are eliminated in our Buck-Boost
chopper type AC voltage controller.
Transformer
Thyristor
Advantages over existing devices:
T/F
Phase
Controlled
Thyristor
circuit
BBCACV
C
Efficiency
Power
factor
Losses
Intial Maint.
Cost
Cost
Harmonic
Injection
Space
occupies
95-99% for
Tr.T/F
50% for
Disb. T/F
Low on
light
loads
More
High
High
Never
More
94-99%
Low
Less
Low
Low
More
Less
97-99% for
Both
Tr.,Disb
Always
high
(Unity)
Less
Low
Low
No
Harmonics
Very Less



It can regulate the output voltage and can maintain
constant voltage at load terminals.
This can be achieved by giving feedback signal to our
Voltage Controller from load terminals through PI
controller.
Due to this feedback it can automatically regulates
the output voltage irrespective of Voltage ‘sags’ &
‘swells’.


The Buck-Boost chopper type AC voltage regulator has many
advantages compared to the winding transformer and thyristor
phase controlled voltage regulator.
The Buck-Boost chopper type AC voltage regulator can
improve the PF and reduce the power loss caused by the
reactive and harmonic currents.