In a 3 phase full wave regulator feeding resistance load connected in star, the

CuriousTab

CuriousTab

Home Aptitude

Discussion

Home ‣ Electronics and Communication Engineering ‣ Power Electronics See What Others Are Saying!

Question
In a 3 phase full wave regulator feeding resistance load connected in star, the possible range of firing angle a is
Options
A. 0 ? a ? 180�
B. 0 ? a ? 150�
C. 0 ? a ? 120�
D. 0 ? a ? 90�

Correct Answer

0 ? a ? 150�

Explanation

Since output voltage is zero if a ? 150�, the possible range of firing angles is 0 ? a ? 150�.

More questions

1. In the below figure, the average value of load current is 15 A. The load is highly inductive. The peak value of thyristor current is
Options
A. 15 A
B. 152 A
C.
D. 30 A

3. A single phase half wave regulator uses
Options
A. 2 diodes and 2 thyristors
B. 2 thyristors
C. 1 diode and 1 thyristor
D. 2 diodes

4. The temperature coefficient of resistivity of semiconductors is
Options
A. positive
B. negative
C. may be positive or negative
D. very low

6. A rectifier is fed by a transformer. The rms voltage and current at secondary of transformer are V_s and I_s. Output dc power is V_dc I_dc and output ac power is (V_rms ) (I_rms), Transformer utilisation factor TUF is
Options
A.
B.
C.
D.

8. In a 3 phase semiconverter, the dc output voltage for a certain firing angle is 50% of the maximum possible value. The firing angle is
Options
A. 30�
B. 60�
C. 90�
D. 120�

10. A single phase half wave converter is used to charge a battery of 50 V. The thyristor is continuously fired by dc signal. Input voltage is v = V_m sin ?t. The thyristor will conduct
Options
A. from 0 to 180�
B. when v > 50 V
C. from 0 to 90�
D. When v < 50 V

Comments

There are no comments.

More in Electronics and Communication Engineering: