Electrical Machines In speed control of DC shunt motor by varying field flux, what may be the value of field regulator? 10 ohm 2 ohm. 100 ohm 0.2 ohm 10 ohm 2 ohm. 100 ohm 0.2 ohm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor when the rotor speed exceeds the synchronous speed during hunting the damper bars develop synchronous motor torque. negative sequence currents are generated. the damper bars develop induction generator torque. the damper bars develop induction motor torque. the damper bars develop synchronous motor torque. negative sequence currents are generated. the damper bars develop induction generator torque. the damper bars develop induction motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 31.1 Ω 31.9 Ω 15.1 Ω 15.9 Ω 31.1 Ω 31.9 Ω 15.1 Ω 15.9 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ia. E = V – IaRa. E = V + IaRa. E = V + Ra. E = V + Ia. E = V – IaRa. E = V + IaRa. E = V + Ra. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is unity power factor lagging power factor None of these leading power factor unity power factor lagging power factor None of these leading power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 0.25Ω. 1Ω. 0.23Ω. 0.5Ω. 0.25Ω. 1Ω. 0.23Ω. 0.5Ω. ANSWER DOWNLOAD EXAMIANS APP