1.
An ideal regulated power supply should have
2.
What is the control element in an SCR?
3.
What are some areas where GTO is applicable?
4.
A single-phase half wave rectifier circuit has a freewheeling diode. The freewheeling diode will conduct only if
5.
The specified maximum junction temperature of thyristors is about
6.
The torque produced by a single-phase induction motor fed through an ac voltage controller for speed control is due to
7.
The di/dt protection for an SCR is achieved through the use of
8.
The three terminals of an SCR are the
9.
A thyristor can be termed as
10.
ECG stands for electrocardiography while EEG stands for?
11.
A power supply has full-load voltage of 24V. What is its no-load voltage for 5% regulation (rounded to the nearest integer) ?
12.
In a feedback series regulator circuit, the output voltage is regulated by controlling the
14.
The peak reverse blocking voltage of an IGBT is nearly
15.
When the temperature increases, the intrinsic stand off ratio
16.
Which one of the following is NOT the advantage of solid state switching of ac capacitors into ac supply over relay-based switching?
17.
Current in SCR to turn on transient can be reduced by
18.
For an SCR, dv/dt protection is achieved through the use of
19.
Which of the following configurations is used for both motoring and regenerative braking?
20.
For a BJT α = 0.98, then β =
21.
Control system that maintains a speed voltage, or other variable within specified limits of a preset level.
22.
Which semiconductor power device, out of the following, is not a current triggered device?
24.
The input power factor of the converter is
25.
A motor armature supplied through phase controlled SCRs receives a smoother voltage shape at
26.
An advantage of cycloconverter is
27.
An SCR is considered to be a semicontrolled device because
28.
In a single-phase semiconverter with resistive load and for a firing angle α , each SCR conduction and freewheeling action takes place
29.
Which of the following is a common application of UJT?
30.
What is that voltage above when the SCR enters the conduction region?
31.
Which of the following can change the angle of conduction in SCR?
32.
Which of the following is NOT a method primarily used for density sensing?
33.
AC power in a load can be controlled by connecting
35.
di/dt protection is provided to the thyristor by
36.
The sharing of the voltage between thyristors operating in series is influenced by their
37.
Carrier frequency gate drive is used for turn-on of a thyristor to reduce.
38.
An SCR is a member of what family?
39.
A single-phase full converter gives maximum and minimum output voltage at firing angles of
40.
An RC snubber circuit is used to protect a thyristor against:
41.
The voltage across an SCR when it is turned on is about
42.
Once an SCR is turned on, it remains so until the anode current goes below
43.
Which one of the following statements is correct? In the case of load regulation
44.
Turned-on of a thyristor takes place when
45.
The triac can be used only in
46.
A thyristor has its gate current zero. To start conduction the forward voltage must exceed
47.
The dv/dt effect in SCR can result in
48.
Which one of the following is the most suitable device for a dc to dc converter?
49.
The main advantage of IGBT over SCR in power electronics is
50.
In a thyristor dc chopper, which type of commutation results in best performance ?
