Question 1:
a) Draw the circuit of a half-wave-rectifier and find the ripple factor, % regulation, efficiency and PIV.
b) Compare the performance of Inductor filter and capacitor filter.
Question 2: With appropriate diagrams, describe the working of centre-tapped full wave rectifier. Derive expressions for VDC, IDC, Vrms and Irms for it
Question 3:
a) Describe the working of Bridge rectifier with required sketches and parameters.
b) Describe the relative advantages and disadvantages of all the rectifiers.
Question 4:
a) Define the given terms of a rectifier and filter:
• Ripple Factor.
• Regulation.
• Rectification Efficiency.
• Form Factor.
b) What is the ripple factor if a power supply of 220 V, 50 Hz is to be Full Wave rectified and filtered with a 220µF capacitor before delivering to a resistive load of 120Ω? Calculate the value of capacitor for the ripple factor to be less than 15%.
Question 5:
a) Derive expressions for ripple factor of a Full Wave Rectifier with and without a capacitive filter.
b) Calculate the average and RMS load currents, TUF of an unfiltered centre tapped Full Wave Rectifier specified below.
Input voltage to transformer = 220 V/50 Hz.
Step down ratio of centre tapped transformer = 4:1(Primary to each section secondary).
Sum of transformer secondary winding in each secondary segment and diode forward resistance = 100Ω.
Load resistance, RL = 220Ω.
Question 6:
a) Define the term Ripple factor and form factor. Establish a relation between them.
b) Describe the need of a bleeder resistor in an L – section filter used with a Full Wave filter.
c) Calculate ripple factor of an L – section choke input filter used at the output of a Full wave rectifier. Capacitor values of the filter are given as 10 H and 8.2 µF correspondingly
Question 7:
a) List out the advantages and disadvantages of Bridge type Full Wave rectifiers over centre tapped type Full Wave rectifiers.
b) The secondary voltages of a centre tapped transformer are given as 60V-0V-60V the total resistance of secondary coil and forward diode resistance of each section of transformer secondary is 62Ω. Calculate the following for a load resistance of 1 KΩ.
• Average load current
• Percentage load regulation
• Rectification efficiency
• Ripple factor for 240 V/50Hz supply to primary of transformer.
c) What is bleeder resistance in L – section filters?