Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.75 p.u 0.25 p.u 0.5 p.u 0.125 p.u 0.75 p.u 0.25 p.u 0.5 p.u 0.125 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine torque depends on which of the following? both A and B flux (φ) speed armature current (I) both A and B flux (φ) speed armature current (I) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In electric locomotive which of the following motor are used ? DC series motor. Synchronous motor. Shunt motor. Separately compound motor. DC series motor. Synchronous motor. Shunt motor. Separately compound motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the e.m.f. generated by a 4 pole lap connected DC Generator rotating at 1500 r.p.m.? Its flux per pole is 0.4 mWb and total no of armature conductors is 1000. 20 volts. 30 volts. 10 volts. 40 volts. 20 volts. 30 volts. 10 volts. 40 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause double frequency currents in the rotor. heating of rotor. All of these vibrations. double frequency currents in the rotor. heating of rotor. All of these vibrations. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Magnetic field of a DC generator is produced by what? Both B and C. None of the options. Permanent magnets. Electromagnets. Both B and C. None of the options. Permanent magnets. Electromagnets. ANSWER DOWNLOAD EXAMIANS APP