AE-JE Foundation EE Electrical Machines Revision Quiz

Which of the following is not the method of reducing harmonics?

An autotransformer has V₁, I₁ as input quantities and V₂, I₂ as output quantities With V₂ < V₁. The V_A transformed from primary to secondary is

Enclosure of motor is made from

A three phase, 4-pole and 50 Hz induction motor have rotor copper loss equal to 400 W. The torque developed by the motor at 5% slip will be.

A 3-phase induction motor has a full-load slip of 3 percent at normal voltage. What will be the value of slip if it develops the same torque theoretically while operating at 110 percent of normal voltage?

For a 3-phase synchronous motor, if air gap is increased, then what will be its effect on voltage regulation?

In case of 3- ϕ IM, shaft power is 2700 W and mechanical losses are 180 W. At a slip of 4%, The rotor ohmic losses will be:

A stepper motor with stator and rotor teeth of 12 and 10 respectively. The value of single step of stepper motor will be:

A 50 kVA, 2200/110V transformer when tested gave S.C. test 90V, 20.5A, 808W (H.V. Side). Calculate the % Voltage regulation at full load with 0.8 p.f. lagging?

Potier triangle method is helpful in obtaining the voltage regulation of synchronous machines by determining the armature