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) = R₀ / R_L

But, R_o = emf resistance + forward resistance

= 0.4 + 0.15

= 0.55

V_R = R₀ / 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 %