Data from short-circuit and open-circuit tests of a step down 203.28-kVA, 1210-110 V, 60 Hz single-phase...

  

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Data from short-circuit and open-circuit tests of a step down 203.28-kVA, 1210-110 V, 60 Hz single-phase transformer are as follows Voc=1210 V Io = 3.8 A Poc=860 watt Determine, (a) The magnetizing reactance Xm and Rse referred to the low voltage side. Vse 140.8 V Inc=168.0 A P=2250 watt (b) The perunit parameters Xeq ,Req (c) The efficiency at 90% of the full load and 0.7071 power factor lagging (d) The voltage regulation at 90% of the full load and 0.7071 power factor leading (e) The actual primary input voltage to give rated output voltage at 85% of the full load and 0.866 power factor lagging. (f) If the cross section area of the transformer is 800 cm² and the mean lengh of the core is 3.5 meter, find the flux and the reluctance of the transformer at no load (uo 4x107 µ-3600, Number of turns in the low voltage side=440 turns.) A 180-V, 18 hp, 3500 r/min shunt motor, operating at rated conditions, has an efficiency of 88% at rated load. The motor parameters are: R₁=0.031 Rew=0.01 Q R 0.015 Rshunt=450, No. of turns/pole of the shunt field = 1250 turns The magnetization curve is shown (see page 6). Determine: (a) The armature current at rated conditions; (b) The armature induced voltage when operating at rated conditions; (c) The developed rated mechanical torque in Nm (d) The rotational losses at rated conditions (mechanical losses) (e) if the demagnitzation due to armature reaction at full is 900 A.turns find the rotor speed at no load with armature current of 1A. (ignore armature reaction at no load) comment about the effect of the armature reaction. Data from short-circuit and open-circuit tests of a step down 203.28-kVA, 1210-110 V, 60 Hz single-phase transformer are as follows Voc=1210 V Io = 3.8 A Poc=860 watt Determine, (a) The magnetizing reactance Xm and Rse referred to the low voltage side. Vse 140.8 V Inc=168.0 A P=2250 watt (b) The perunit parameters Xeq ,Req (c) The efficiency at 90% of the full load and 0.7071 power factor lagging (d) The voltage regulation at 90% of the full load and 0.7071 power factor leading (e) The actual primary input voltage to give rated output voltage at 85% of the full load and 0.866 power factor lagging. (f) If the cross section area of the transformer is 800 cm² and the mean lengh of the core is 3.5 meter, find the flux and the reluctance of the transformer at no load (uo 4x107 µ-3600, Number of turns in the low voltage side=440 turns.) A 180-V, 18 hp, 3500 r/min shunt motor, operating at rated conditions, has an efficiency of 88% at rated load. The motor parameters are: R₁=0.031 Rew=0.01 Q R 0.015 Rshunt=450, No. of turns/pole of the shunt field = 1250 turns The magnetization curve is shown (see page 6). Determine: (a) The armature current at rated conditions; (b) The armature induced voltage when operating at rated conditions; (c) The developed rated mechanical torque in Nm (d) The rotational losses at rated conditions (mechanical losses) (e) if the demagnitzation due to armature reaction at full is 900 A.turns find the rotor speed at no load with armature current of 1A. (ignore armature reaction at no load) comment about the effect of the armature reaction.