Controlled rectifier, Slides of Power Electronics

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Single-Phase Half-Wave Rectifier

Waveforms

Performance Parameters

• (^) Average value of the output voltage, V dc
• (^) Average value of the output current, I dc
• (^) Output dc power, P dc
• P dc = V dc I dc
• (^) rms value of the output voltage, V rms
• (^) Output ac power, P ac
• (^) P ac = V rms I rms

Performance Parameters (continued)

• (^) Efficiency, η
  • η = P dc /P ac
• (^) Effective (rms) value of the ac component

of the output voltage, V ac

• (^) V ac = V rms

2

• V dc

2

• (^) Form factor, FF
  • (^) FF = V rms /V dc
• (^) Ripple factor, RF
  • (^) RF = V ac /V dc

Input Voltage and Current

Performance Parameters (continued)

• (^) Displacement angle, Φ
• (^) Displacement Factor, DF
  • (^) DF = cos(Φ)
• (^) Harmonic Factor, HF

1

2 2 2 1

2 1 2

2

1 1

s s s

s s

I I I

HF

I I

^  

Performance Parameters (continued)

• (^) Crest Factor, CF

s ( peak)

s

I

CF

I



Example 3.

• (^) Determine η, FF, RF, TUF, PIV of the

diode, CF of the input current, input PF.

1

2

m

dc m

dc m

dc

f

T

f

V

V V

V V

I

R R

 







 

 

Determine the rms Voltage, V

rms

1 2 2 0 1 2 2 2 0

( sin )

T

rms L

T

rms m

m

rms m

rms m

rms

V v t dt

T

V V t dt

T

V

V V

V V

I

R R







Determine FF and RF

2

2

1.57 157%

1

1.57 1 1.21 121%

rms m

dc m

V V

FF

V V

FF

RF FF

RF

 

 

 

   

Determine the TUF

1

2

2

0

2

( sin ) 0.

T m

s m m

m

s load

m

dc

m s s m

V

V V t dt V

T

V

I I

R

V

P

R

T UF

V

V I

V

R

T UF

^ 

Determine CF

( )

( )

2

s peak

s

m

s peak

m

s

m

m

I

CF

I V I R V I R V R

CF

V

R







 

Determine PF

2

cos

(0.5 )

(0.707 )( )

ac

m

m

m

P

PF

VA

V

R

PF

V

V

R

  

 