1
GATE EE 2009
MCQ (Single Correct Answer)
+2
-0.6
Match the switch arrangements on the top row to be steady $$-$$ state $$V$$ - $$I$$ characteristics on the lower row. The steady state operating points are shown by large black dots.
2
GATE EE 2007
MCQ (Single Correct Answer)
+2
-0.6
A $$1:1$$ pulse transformer $$(PT)$$ is used to trigger the $$SCR$$ in the adjacent figure. The $$SCR$$ is rated at $$1.5$$ $$kV$$, $$250$$ $$A$$ with $${{\rm I}_L} = 250\,mA,\,\,{{\rm I}_H} = 150\,mA,$$ and $${{\rm I}_{G\max }} = 150mA$$ with $${{\rm I}_L} = 250\,mA,$$ $${{\rm I}_{G\min }} = 100mA.$$ The $$SCR$$ is connected to an inductive load, where $$L$$ $$=150$$ $$mH$$ in series with a small resistance and the supply voltage is $$200$$ $$V$$ $$dc.$$ The forward drops of all transistors/diodes and gate $$-$$ cathode junction during $$ON$$ state are $$1.0V$$
The minimum approximate volt $$-$$second rating of the pulse transformer suitable for triggering the $$SCR$$ should be: (Volt - second rating is the maximum of product of the voltage and the width of the pulse that may be applied)
3
GATE EE 2007
MCQ (Single Correct Answer)
+2
-0.6
A $$1:1$$ pulse transformer $$(PT)$$ is used to trigger the $$SCR$$ in the adjacent figure. The $$SCR$$ is rated at $$1.5$$ $$kV$$, $$250$$ $$A$$ with $${{\rm I}_L} = 250\,mA,\,\,{{\rm I}_H} = 150\,mA,$$ and $${{\rm I}_{G\max }} = 150mA$$ with $${{\rm I}_L} = 250\,mA,$$ $${{\rm I}_{G\min }} = 100mA.$$ The $$SCR$$ is connected to an inductive load, where $$L$$ $$=150$$ $$mH$$ in series with a small resistance and the supply voltage is $$200$$ $$V$$ $$dc.$$ The forward drops of all transistors/diodes and gate $$-$$ cathode junction during $$ON$$ state are $$1.0V$$
The resistance $$R$$ should be
4
GATE EE 2006
MCQ (Single Correct Answer)
+2
-0.6
An $$SCR$$ having a turn ON time of $$5\,\,\mu \,\,\sec $$, latching current of $$50$$ $$mA$$ and holding current of $$40$$ $$mA$$ is triggered by a short duration pulse and is used in the circuit shown in figure The minimum pulse width required To turn the $$SCR$$ ON will be
GATE EE Subjects
Browse all chapters by subject
Electric Circuits
Electrical Machines
Engineering Mathematics
Signals and Systems
Power Electronics
Power System Analysis
Digital Electronics
Analog Electronics
Electromagnetic Fields
Control Systems
Electrical and Electronics Measurement
General Aptitude