Power Electronics Questions

• Inverters find applications in
• It is possible to use a freewheeling diode in
• The leads in a TRIAC are denoted by
• Assertion (A): A GTO can be turned on and turned off by gate pulses Reason (R): A GTO can be turned off by negative gate pulse.
• As the firing of a thyristor is delayed, the output voltage of a controlled rectifier decreases.
• Assertion (A): When the anode current of an SCR starts increasing during turn on process, the anode cathode voltage drop starts decreasing. Reason (R): During turn on the reverse biased junction in SCR breaksdown.
• When a thyristor is conducting, the voltage drop across it
• The static equalisation circuit for thyristors connected in series is
• The advantage of modified series inverter with two inductors and two capacitors is
• A fully controlled bridge converter can operate in quadrants
• A TRIAC is equivalent to
• Assertion (A): The output voltage of an inverter can be controlled by PWM technique Reason (R): In a current source inverter the input current is constant.
• An SUS is
• In a half bridge inverter the gate pulses of the two thyristors have a phase displacement of
• The cut in voltages for germanium and silicon diodes respectively as
• The symbol in figure is for
• A cycloconverter is a group of controlled rectifiers.
• In a certain inverter circuit each thyristor carries 26.67 A for 60°, 13.33 A for 120° and zero A for 180° of the cycle. The rms current of thyristor is
• Which of the following devices has two gates?
• The factor η for a UJT is about