This PPT consist the details about the single phase converter.

1. SEMINAR ON SINGLE
PHASE CONVERTER
By
Vinod Srivastava
M.E. Modular I & C
Roll No.151522

2. INTRODUCTION
AC(~) DC(--)
Diode rectifiers are uncontrolled rectifiers
The level of DC output voltage can not be
controlled.
e.g. single phase half wave and full wave
rectifiers.

3. Single phase Full Wave Bridge
Rectifier
.
A.C. in
D.C. out

4. CONTROLLED RECTIFIER
 Rectifier designed with SCR’s are
controlled rectifier.
 AC is converted into regulated DC.
 The phase relationship between i/p
voltage & o/p current can be controlled.
 Level of the voltage can be regulated by
varying firing angle α.

5. Classification-
• Single phase converter
Half wave converter
Full wave converter
• Three phase converter
Half wave converter
Full wave converter

6. Single Phase Half Wave Rectifier
Fig(a) Half wave rectifier for resistive load

7. Average value of output voltage





ttdvv iav sin2
2
1
On solving
)cos1(
2
 i
av
v
v

8. RESISTIVE – INDUCTIVE
LOAD

9. Contd….
 Thyristor turns ON at ωt= α & voltage
appears across Load & current starts
building up.
 Inductor does not changes current
instantaneously, so load current does not
become zero at ωt = π.

10. Average value of output voltage





ttdvv iav sin2
2
1
)cos(cos
2
, 

 i
av
v
vonsolving

11. SINGLE PHASE CONVERTER
Fig-single phase thyristor controlled rectifier with Ls=0

12. Input and output response

13. Operation
 In the positive half cycle T1 and T2 are
forward biased.
 In the negative half T3 and T4 are forward
biased.
 T1 and T2 continue to conduct till T3 and
T4 are triggered.

14. Contd….
 T1T2 α to π + α
 T3T4 π + α to 2π + α
 α to π Vo +ve
 α to π Io +ve
 π to π + α Vo -ve
 π to π + α Io +ve
 α to π L stores the energy.
 π to π + α L releases the energy.

15. AVERAGE VALUE OF
OUTPUT VOLTAGE
ttdvV mav 



sin
1





cos
2 m
av
v
V 
onsolving
Thus, Vav is +ve from o ˂α ˂ π/2
Vav is –ve from π/2 ˂ α ˂ π
Vo
Io
-Vo

16. Line Current

17. Contd….
Eq…(1)
Eq…(2)
Eq…..(
3)
Eq…..(4)
Eq…..(5)
The current Is in fig a can be expressed in terms
of its fourier components as-
Where only odd harmonics are present
Rms value of
is1

18. Power, power factor and reactive
volt amperes
(a)
(2), (4) &
(6)
(2
)
(6
)
8
Eq…(6)
Eq…(7)
Eq…(8)
Eq…(9)
Eq…(10)
Eq…(11)

19. Effect of Ls
Fig (c)
Fig (e)
Fig (d)

20. Contd….
 The effect of inductance can not be
ignored in practical thyristor
converters.
 The current commutation takes a finite
commutation interval u as in fig (d)

21. Fig(c)
Eq…(12
)
Eq…(13
)
(13)
Eq…(14)
(14) (13)
Eq…(15
)
Eq…(16
)
Eq…(17)

22. Contd….
Eq……(18)