Very large values of modulation index (greater than 3.24) lead to___________?
(A) Square AC output voltage
(B) Sine AC output voltage
(C) Triangular AC output voltage
(D) Trapezoidal AC output voltage
Any electrical signal present in a circuit other than the desired signal is known as______________?
(A) Noise
(B) Distortion
(C) Interference
(D) All of these
The advantage of using free – wheeling diode in half controlled bridge converter is that
(A) There is always a path for the dc current independent of the ac line
(B) There is always a path for the ac current independent of the ac line
(C) There is always a path for the dc current dependent of the ac line
(D) There is always a path for the ac current independent of the ac line
To detect an over – current fault condition, the most reliable method is to connect a_____________?
(A) Current sensor across IGBT
(B) Voltage sensor across IGBT
(C) Current sensor in series with IGBT
(D) Voltage sensor in series with IGBT
Harmonics in 3 phase inverters can be reduced by using___________?
(A) Passive filter
(B) Active filter
(C) Both passive and active filters
(D) None of these
The on – state voltage drop of IGBT consists of__________?
(A) Drop across the collector junction
(B) Drop across the drift region
(C) Drop across MOSFET portion
(D) All of these
The most suited gate pulses given to the AC regulator with R – L load can be in the form of____________?
(A) Continuous signal
(B) Large isolating pulse transformer
(C) A train of pulses
(D) None of these
The maximum firing angle in the half wave controlled regulator is_____________?
(A) 180 degree
(B) 190 degree
(C) 200 degree
(D) 210 degree
With increase in firing angle,
(A) Both harmonic distortion and quality of input current increases
(B) Harmonic distortion increases and quality of input current decreases
(C) Harmonic distortion decreases and quality of input current increases
(D) Both harmonic distortion and quality of input current decreases
n a phase controlled 3 phase ac voltage controller, the harmonic present is__________?
(A) 2nd
(B) 3rd
(C) 5th
(D) 7th