# A single-phase half-wave controlled rectifier has 400 sin 314 t as the input voltage and R as the load. For the firing angle of 60o for the SCR, the average output voltage is

1.

2.

3.

4.

4

Explanation :
No Explanation available for this question

# If in a 3-phase, half-wave rectifier, if per phase input voltage is 200 V, then average output voltage is

1.  233.91 V

2.  116.95 V

3.  202.56 V

4.  101.28 V

4

233.91 V

Explanation :
No Explanation available for this question

# Analysis of voltage waveform of a single phase bridge converter shows that it contains x% of 6th harmonic. The 6th harmonic content of the voltage waveform of a 3-phase bridge converter would be

1.  less than x% due to an increase in the number of pulses

2.  equal to x%, the same as that of the single phase converter

3.  greater than x% due to changes in the input and output voltages of the converter

4.  difficult to predict as the analysis of converters in not governed by any generalized theory

4

greater than x\% due to changes in the input and output voltages of the converter

Explanation :
No Explanation available for this question

# A 3-phase converter feeds a pure resistivfe load at a firing angle of α = 60o. The average value of current flowing in the load is 10 A. If a very large inductance is connected in the load circuit, then

1.  average value of current will remain as 10 A

2.  average value of current will become greater than 10 A

3.  average value of current will become less than 10 A

4.  trend of variation of current cannot be predicted unless the exact value of the inductance connected is known

4

average value of current will remain as 10 A

Explanation :
No Explanation available for this question

# In a 3-phase rectifier circuit, thyristor number 1, 2 and 3 are connected respectively to R, Y and B phases of the star-connected transformer secondary. When the current is being commutated from thyristor No. 1 to No. 2, the effect of the transformer leakage and the ac system inductances will be such that it will

1.  prolong the conduction in No. 1 and delay the turn-on of No. 2 correspondingly

2.  stop the conduction in No. 1 at the scheduled time, but delay the turn-on of No. 2

3.  produce conduction in both No. 1 and No. 2 in parallel for an overlapping period through a transient

4.  double the voltage output through a commutation transient

4

produce conduction in both No. 1 and No. 2 in parallel for an overlapping period through a transient

Explanation :
No Explanation available for this question

# In the given figure, the type of load is

3.  dc motor

4

dc motor

Explanation :
No Explanation available for this question

# A single phase diode bridge rectifier supplies a highly inductive load. The load current can be assumed to be ripple free. The ac supply side current waveform will be

1.  sinusoidal

2.  constant dc

3.  square

4.  triangular

4

square

Explanation :
No Explanation available for this question

# In a 3-phase controlled bridge rectifier, with an increase of overlap angle, the output dc voltage

1.  decreases

2.  increases

3.  does not change

4

decreases

Explanation :
No Explanation available for this question

# AC-to-DC circulating current dual converters are operated with which of the following relationship between their triggering angles (α1 and α2)

1.  α1 +α2 = 180o

2.  α1 +α2 = 360o

3.  α1 -α2 = 180o

4.   α1 +α2 = 90o

4

α12 = 180o

Explanation :
No Explanation available for this question

# In a dual converter, the circulating current

1.  allows smooth reveral of load current, but increases the response time

2.  does not allow smooth reversal of load current, but reduces the response time

3.  allows smooth reversal of load current with improved speed of response

4.  flows only if there is no interconnecting inductor

4