A. Voltage across the commutating inductances collapses
B. The capacitance voltage adds to the supply voltage
C. Both A. and B.
D. None of these
Related Mcqs:
- In the operation and control of both naturally commutated and forced commutated SCR base converter, commutation plays an important role. The converters is / are ___________?
A. AC – DC
B. DC – DC
C. DC – AC
D. All of these - In a load commutated DC – DC chopper, the capacitor has a_____________?
A. Symmetric triangular voltage across itself
B. Symmetric rectangular voltage across itself
C. Symmetric trapezoidal voltage across itself
D. Symmetric sinusoidal voltage across itself - Choppers is a_______________?
A. AC – DC converters
B. AC – AC converters
C. DC – AC converters
D. DC – DC converters - A step – down choppers can be used in___________?
A. Electric traction
B. Electric vehicles
C. Machine tools
D. All of these - A single phase one pulse controlled circuit has a resistance R and counter emf E load 400 sin(314 t) as the source voltage. For a load counter emf of 200 V, the range of firing angle control is _____?
A. 30° to 150°.
B. 30° to 180°.
C. 60° to 120°.
D. 60° to 180°. - ON state voltage drop across SCR lie between the range_____________?
A. 0 – 0.5 V.
B. 0.5 – 1 V.
C. 1 – 1.5 V.
D. 1.5 – 2 V. - In a full bridge VSI, in order to avoid the short circuit across the DC bus and the undefined AC output voltage condition, the modulating technique should ensure that___________?
A. Top switch of each leg is on at any instant
B. Bottom switch of each leg is on at any instant
C. Either A. or B.
D. None of these - A step up chopper has input voltage 110 V and output voltage 150 V. The value of duty cycle is_____?
A. 0.32
B. 0.67
C. 0.45
D. 0.27 - Under over voltage condition impedance offered by the voltage clamping device is__________?
A. low
B. High
C. moderate
D. infinity - A thyristor string is made of a no. of SCR connected in series and parallel. The string have volume and current of 11 KV and 4 KA. The voltage and current rating of available SCRs are 1800 V and 1000 A. For a string efficiency of 90 % let the number of SCRs in series and parallel are a and b respectively. Then the value of a and b will be_____________?
A. 5, 7
B. 4, 6
C. 7, 5
D. 6, 4
