# Numerical - Voltage regulation and efficiency of a half-wave rectifier circuit with silicon diode

**Determine the voltage regulation and efficiency of a half-wave rectifier circuit that uses silicon diode with a forward resistance of 0.15 ohm, load resistance of 15 ohm, threshold voltage of about 0.7 V and emf at secondary winding is about 16 V**_{rms} including the emf resistance of about 0.4 ohm

**Options:**

a. 4.8 % & 36.06 %

b. 1.2 % & 36. 06%

c. 2.5 % & 42.06%

d. 3.6 % & 42.06 %

Correct Answer: d. 3.6 % & 42.06 %

**Explanation:**

Considering the half-wave rectifier circuit,

(i) Voltage Regulation (V_{R}) = R_{0} / R_{L}

But, R_{o} = emf resistance + forward resistance

= 0.4 + 0.15

= 0.55

V_{R} = R_{0} / R_{L}

= 0.55 / 15 = 0.036 or 3.6 %

Efficiency (η) = P _{dc} / P_{in} = 40.6 / ( 1+ Ro / R_{L} )

= 40.6 ( 1 + 0.55 / 15 )

= 42.06 %