1
GATE EE 2007
+2
-0.6
A three phase squirrel cage induction motor has a starting current of seven times the full load current and full load slip of $$5\%$$

If an auto-transformer is used for reduced voltage starting to provide $$1.5$$ per unit starting torque, the auto-transformer ratio $$\left( \% \right)$$ should be

A
$$57.77\%$$
B
$$72.56\%$$
C
$$78.25\%$$
D
$$81.33\%$$
2
GATE EE 2007
+2
-0.6
A three phase squirrel cage induction motor has a starting current of seven times the full load current and full load slip of $$5\%$$

If a star-delta starter is used to start this induction motor, the per unit staring torque will be

A
$$0.607$$
B
$$0.816$$
C
$$1.225$$
D
$$1.616$$
3
GATE EE 2007
+2
-0.6
A three phase squirrel cage induction motor has a starting current of seven times the full load current and full load slip of $$5\%$$

If a starting torque of $$0.5$$ per unit is required then the per unit starting current should be

A
$$4.65$$
B
$$3.75$$
C
$$3.16$$
D
$$2.13$$
4
GATE EE 2006
+2
-0.6
The speed of a $$4$$-pole induction motor is controlled by varying the supply frequency while maintaining the ratio of supply voltage to supply frequency $$(V/f)$$ constant. At rated frequency of $$50$$ $$Hz$$ and rated voltage of $$400$$ $$V$$ its speed is $$1440$$ $$rpm$$. Find the speed at $$30$$ $$Hz,$$ if the load torque is constant
A
$$882$$ $$rpm$$
B
$$864$$ $$rpm$$
C
$$840$$ $$rpm$$
D
$$828$$ $$rpm$$
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
EXAM MAP
Joint Entrance Examination