Controlled rectifier

Which semiconductor device is commonly used as a controlled switch in half-wave rectifiers?

• Diode

• Transistor

• Thyristor (SCR)

• Capacitor

What is the firing angle in a controlled half-wave rectifier circuit? A) C) D)

Model Answer: B) The angle at which the thyristor is triggered to conduct

• The angle at which the output voltage becomes zero

• The angle between the positive peak of the input voltage and the start of conduction

• The angle between the negative peak of the input voltage and the end of conduction

• The angle at which the thyristor is triggered to conduct

What is the advantage of controlling the firing angle in a half-wave rectifier circuit?

• It reduces power losses.

• It allows for variable DC output voltage

• It increases the efficiency of the rectifier.

• It prevents voltage spikes.

In a controlled half-wave rectifier, if the firing angle is 60 degrees, what is the conduction angle? A) B) C) D)

• 60 degrees

• 90 degrees

• 120 degrees

• 180 degrees

What happens to the average output voltage of a controlled half-wave rectifier when the firing angle is increased? A) B) . C) D)

• It increases.

• It remains constant

• It decreases.

• It becomes zero.

What is the key difference between a controlled full-wave rectifier and an uncontrolled full-wave rectifier? A) B) C) D)

• Controlled rectifiers use diodes, while uncontrolled rectifiers use transistors.

• Controlled rectifiers can regulate the output voltage, unlike uncontrolled rectifiers.

• Uncontrolled rectifiers are more efficient than controlled rectifiers.

• Controlled rectifiers work only with AC input, while uncontrolled rectifiers work with both AC and DC inputs.

For a controlled full-wave rectifier with a firing angle of 45 degree, what is the RMS output voltage if the peak voltage of the input AC signal is 100 V? A) 70.71 V70.71V B) 50 V50V C) 100 V100V D) 85.85 V85.85V

• 50

• 27.17

• 54.33

• 85

If the load resistance in a controlled half-wave rectifier circuit is RL​=10Ω, and the firing angle α=60∘, what is the DC output current if the peak voltage of the input AC signal is 220 V?

• 76

• 105 V

• 52.52 V

• 86