PPT - Autotransformers | Electrical Machines - Electrical Engineering (EE) PDF Download

 Page 1


      
      
Autotransformer
Autotransformer
Page 2


      
      
Autotransformer
Autotransformer
  
  
A wide variety of transformer designs are used 
A wide variety of transformer designs are used 
for different applications.
for different applications.
?
Auto-transformer
?
Poly-phase transformer
Poly-phase transformer
?
Leakage transformer
Leakage transformer
?
Resonant transformer
Resonant transformer
?
Instrument transformers 
Instrument transformers 
China autotransformer
Page 3


      
      
Autotransformer
Autotransformer
  
  
A wide variety of transformer designs are used 
A wide variety of transformer designs are used 
for different applications.
for different applications.
?
Auto-transformer
?
Poly-phase transformer
Poly-phase transformer
?
Leakage transformer
Leakage transformer
?
Resonant transformer
Resonant transformer
?
Instrument transformers 
Instrument transformers 
China autotransformer
AUTO-TRANSFORMERS
AUTO-TRANSFORMERS
?
An 
An 
autotransformer
autotransformer
 
 
(sometimes called 
(sometimes called 
auto 
auto 
step down 
step down 
transformer
transformer
)is an 
)is an 
electrical 
electrical 
transformer
transformer
 
 
with only one 
with only one 
winding
winding
. 
. 
The "
The "
auto
auto
" (Greek for 
" (Greek for 
"self") prefix refers to 
"self") prefix refers to 
the single coil acting on 
the single coil acting on 
itself and not to any 
itself and not to any 
kind of 
kind of 
automatic 
automatic 
mechanism
mechanism
.
.
Page 4


      
      
Autotransformer
Autotransformer
  
  
A wide variety of transformer designs are used 
A wide variety of transformer designs are used 
for different applications.
for different applications.
?
Auto-transformer
?
Poly-phase transformer
Poly-phase transformer
?
Leakage transformer
Leakage transformer
?
Resonant transformer
Resonant transformer
?
Instrument transformers 
Instrument transformers 
China autotransformer
AUTO-TRANSFORMERS
AUTO-TRANSFORMERS
?
An 
An 
autotransformer
autotransformer
 
 
(sometimes called 
(sometimes called 
auto 
auto 
step down 
step down 
transformer
transformer
)is an 
)is an 
electrical 
electrical 
transformer
transformer
 
 
with only one 
with only one 
winding
winding
. 
. 
The "
The "
auto
auto
" (Greek for 
" (Greek for 
"self") prefix refers to 
"self") prefix refers to 
the single coil acting on 
the single coil acting on 
itself and not to any 
itself and not to any 
kind of 
kind of 
automatic 
automatic 
mechanism
mechanism
.
.
      
      
?
N1=primary turn(1-3)
N1=primary turn(1-3)
?
N2=secondary turn(2-3)
N2=secondary turn(2-3)
?
I1=primary current
I1=primary current
?
I2=secondary current
I2=secondary current
?
V1=primary voltage
V1=primary voltage
?
V2=secondary votage
V2=secondary votage
Theory of Autotransformer
Theory of Autotransformer
From the above fig. We get
                
Page 5


      
      
Autotransformer
Autotransformer
  
  
A wide variety of transformer designs are used 
A wide variety of transformer designs are used 
for different applications.
for different applications.
?
Auto-transformer
?
Poly-phase transformer
Poly-phase transformer
?
Leakage transformer
Leakage transformer
?
Resonant transformer
Resonant transformer
?
Instrument transformers 
Instrument transformers 
China autotransformer
AUTO-TRANSFORMERS
AUTO-TRANSFORMERS
?
An 
An 
autotransformer
autotransformer
 
 
(sometimes called 
(sometimes called 
auto 
auto 
step down 
step down 
transformer
transformer
)is an 
)is an 
electrical 
electrical 
transformer
transformer
 
 
with only one 
with only one 
winding
winding
. 
. 
The "
The "
auto
auto
" (Greek for 
" (Greek for 
"self") prefix refers to 
"self") prefix refers to 
the single coil acting on 
the single coil acting on 
itself and not to any 
itself and not to any 
kind of 
kind of 
automatic 
automatic 
mechanism
mechanism
.
.
      
      
?
N1=primary turn(1-3)
N1=primary turn(1-3)
?
N2=secondary turn(2-3)
N2=secondary turn(2-3)
?
I1=primary current
I1=primary current
?
I2=secondary current
I2=secondary current
?
V1=primary voltage
V1=primary voltage
?
V2=secondary votage
V2=secondary votage
Theory of Autotransformer
Theory of Autotransformer
From the above fig. We get
                
(I/P=O/P)
OUT PUT
The primary and secondary windings of an 
autotransformer are
Connected magnetically as well as electrically.
So the power transferred primary to secondary 
inductively as well as conductively.