AUTOMATIC ON LOAD
TRANSFORMER TAP
CHANGER
1
By.
Uren Thummar
Heema Dave
Abhishek Joshi
Shruti Ghetiya
INTRODUCTION


In conventions on Load Transformer Tap
Changer there is production of Arc when
changing the tapping of Transformer. And in
large KVA rating of Transformer it is hard to
quench the Arc. This major problem can solve in
this thyristor based transformer tap changer.
A single phase on Load Transformer Tap
Changer is a basically A.C. Voltage Controller.
Which uses anti-parallel loop of Thyristors.
2
BASIC BLOCK DIAGRAM
SCR loop
1
AC
Transformer
SCR loop
2
SCR loop
3
AC
supply
Tapping
Firing Pulse
Frequency
μ
C
L
O
A
D
F
e
e
d
b
a
c
k
3
ADVANTAGES

Due to the use of thyristors as switches, the
changeover is fast.

Operation and changeover is smooth.

It avoids sparking while changing over.

It reduces size of OLTC.
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