The magnetism characteristic values obtained at 1500 rpm for a direct current motor (separately excited DC...

 

 

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The magnetism characteristic values obtained at 1500 rpm for a direct current motor (separately excited DC motor) with free (Independent) excitation are given in the table below. Accordingly, answer the following questions: a) The engine rotates at 1500 rpm. Armature terminal voltage 790 V, terminal current 50 A and if the inductance is 0.2 02, what is the excitation coil current (field current)? b) The winding resistance of the excitation coil is 20 Q. The excitation winding is from the same voltage source as andavi (790 V) it is desirable to feed. What should be the value of the adjustable resistance (rheostat), which can be set between 0-100 , connected in series to the excitation Decoy, which will ensure that the motor operates under the same operating conditions? c) Calculate the torque of the engine for the values given above? d) Neglecting the armature effect (armature effect) for the case where the excitation current of the motor is constant, the torque-draw speed and torque-industrial current graphs approximately Ea(V) I(A) 50 0 420 4 780 8 Tablo 1 950 10 1120 12.8 1180 14.4 1260 28.8 The magnetism characteristic values obtained at 1500 rpm for a direct current motor (separately excited DC motor) with free (Independent) excitation are given in the table below. Accordingly, answer the following questions: a) The engine rotates at 1500 rpm. Armature terminal voltage 790 V, terminal current 50 A and if the inductance is 0.2 02, what is the excitation coil current (field current)? b) The winding resistance of the excitation coil is 20 Q. The excitation winding is from the same voltage source as andavi (790 V) it is desirable to feed. What should be the value of the adjustable resistance (rheostat), which can be set between 0-100 , connected in series to the excitation Decoy, which will ensure that the motor operates under the same operating conditions? c) Calculate the torque of the engine for the values given above? d) Neglecting the armature effect (armature effect) for the case where the excitation current of the motor is constant, the torque-draw speed and torque-industrial current graphs approximately Ea(V) I(A) 50 0 420 4 780 8 Tablo 1 950 10 1120 12.8 1180 14.4 1260 28.8