1
GATE EE 2001
MCQ (Single Correct Answer)
+2
-0.6
Given the potential function in free space to be $$V\left( x \right) = \left( {50{x^2} + 50{y^2} + 50{z^2}} \right)$$ volts, the magnitude (in volts /metre) and the direction of the electric field at a point $$\left( {1,\,\, - 1,\,\,1} \right),$$ where the dimensions are in metres, are
A
$$100\,\,\,\,;\left( {i + j + k} \right)$$
B
$$100/\sqrt 3 ;\,\,\left( {i - j + k} \right)$$
C
$$100\sqrt 3 ;\,\,\left[ {\left( { - i - j - k} \right) - \sqrt 3 } \right]$$
D
$$100\sqrt 3 ;\,\,\left[ {\left( { - i + j - k} \right) - \sqrt 3 } \right]$$
2
GATE EE 2001
Subjective
+5
-0
A voltage commutated thyristor chopper circuit is shown in fig. The chopper is operated at $$500$$ $$Hz$$ with $$50\% $$ duty ratio. The load takes a constant current of $$20A$$

(a) Evaluate the circuit turn off time for the main thyristor $$T{h_1}$$
(b) Calculate the value of inductor $$L,$$ if the peak current through the main thyristor $$Th,$$ is limited to $$180$$% of the load current.
(c)Calculate the maximum instantaneous output voltage of the chopper

GATE EE 2001 Power Electronics - Choppers and Commutation Techniques Question 20 English
3
GATE EE 2001
MCQ (Single Correct Answer)
+2
-0.6
A single - phase full-bridge voltage source inverter feeds a purely inductive load, as shown in figure. when $${T_1},{T_2},\,\,\,\,\,{T_3},{T_4}$$ are power transistors and $${D_1},{D_2},\,{D_3},{D_4}$$ are feedback diodes. The inverter is operated in square-wave mode with a frequency of $$50$$ $$Hz.$$ If the average load current is zero, what is the time duration of conduction of each feedback diode in a cycle? GATE EE 2001 Power Electronics - Inverters Question 25 English
A
$$5\,\,m\,\,\sec $$
B
$$10\,\,m\,\,\sec $$
C
$$20\,\,m\,\,\sec $$
D
$$2.5\,\,m\,\,\sec $$
4
GATE EE 2001
MCQ (Single Correct Answer)
+1
-0.3
$$AC$$ to $$DC$$ circulating current dual converters are operated with the following relationship between their triggering angles $$\left( {{\alpha _1}} \right.$$ and $$\left. {{\alpha _2}} \right).$$
A
$${\alpha _1} + {\alpha _2} = {180^0}$$
B
$${\alpha _1} + {\alpha _2} = {360^0}$$
C
$${\alpha _1} - {\alpha _2} = {180^0}$$
D
$${\alpha _1} + {\alpha _2} = {90^0}$$