Power Electronics
Choppers and Commutation Techniques
Marks 1Marks 2Marks 5
Single and Three Phase Rectifier
Marks 1Marks 2Marks 5
Power Semiconductor Devices
Marks 1Marks 2
Ac Voltage Controllers
Marks 1Marks 2Marks 5
1
GATE EE 2007
MCQ (Single Correct Answer)
+1
-0.3
A three - phase fully - controlled thyristor bridge converter is used as line commuted inverter to feed $$50kW$$ power $$420$$ $$V$$ $$dc$$ to a three phase, $$415$$ $$V$$ (line), $$50$$ $$Hz$$ $$ac$$ mains, Consider $$dc$$ link current to be constant. The $$rms$$ current of the thyristor is
A
$$119.05$$ $$A$$
B
$$79.37$$ $$A$$
C
$$68.73$$ $$A$$
D
$$39.68$$ $$A$$
2
GATE EE 2007
MCQ (Single Correct Answer)
+1
-0.3
''Six $$MOSFETS$$ connected in a bridge configuration (having no other power device) MUST be operated as Voltage Source Inverter $$(VSI)''.$$ This statement is
A
True, because being majority carrier devices. $$MOSFETS$$ are voltage driven
B
True, because $$MOSFETs$$ have inherently anti - parallel diodes
C
False, because it can be operated both as Current Source Inverter $$(CSI)$$ or a $$VSI$$
D
False, because $$MOSFETs$$ can be operated as execellent constant current sources in the saturation region
3
GATE EE 2005
MCQ (Single Correct Answer)
+1
-0.3
The output voltage waveform of a three - phase square-wave inverter contains
A
only even harmonics
B
both odd and even harmonics
C
only odd harmonics
D
only triple harmonics
4
GATE EE 2000
MCQ (More than One Correct Answer)
+1
-0
Triangular $$PWM$$ control, when applied to a $$BJT$$ based three phase voltage source inverter, introduces.
A
low order harmonic voltages on the $$dc$$ side.
B
very high order harmonic voltage on the $$dc$$ side
C
low order harmonic voltage on the $$ac$$ side
D
very high order harmonic voltage on the $$ac$$ side
GATE EE Subjects
Electromagnetic Fields
Signals and Systems
Engineering Mathematics
General Aptitude
Power Electronics
Power System Analysis
Analog Electronics
Control Systems
Digital Electronics
Electrical Machines
Electric Circuits
Electrical and Electronics Measurement