Electrical Machines A slip ring Induction motor runs at 290 rpm at full load, when connected to 50 Hz supply. Determine the number of poles and slip. P = 50, s = 4.43 %. P = 20, s = 3.33 %. P = 60, s = 0.96 %. P = 40, s = 5.79 %. P = 50, s = 4.43 %. P = 20, s = 3.33 %. P = 60, s = 0.96 %. P = 40, s = 5.79 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor especially the cage rotors slots are nearly parallel to shaft axis. This is called crawling. cogging. slip. skewing. crawling. cogging. slip. skewing. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator frame in an induction motor is used to provide return path for the flux. ventilate the armature. hold armature stamping in position. protect the whole machine. provide return path for the flux. ventilate the armature. hold armature stamping in position. protect the whole machine. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When maximum flux density is constant, the eddy current losses are proportional to f2 f V V2 f2 f V V2 ANSWER DOWNLOAD EXAMIANS APP
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 0.125 p.u 0.25 p.u 0.5 p.u 0.75 p.u 0.125 p.u 0.25 p.u 0.5 p.u 0.75 p.u ANSWER DOWNLOAD EXAMIANS APP