b) A single-phase transformer with 10: 1 turns-ratio and rated at 50 kVA, 2400-V/240-V, 50-Hz is used tostep down the voltage of a distribution system, The low tension (LT) voltage is to be kept constant at 240V. Find the value of the load impedance of the LT side so that the transformer is loaded fully. Find alsothe value of the maximum flux inside the core if the LT side has 23 turns.(c) A 2-pole, 3-phase induction motor delivers 37 hp at the shaft at a speed of 2850 rpm on 500 V, 50 Hz supply.The mechanical losses are 3.5 hp and the power factor of operation is 0.85. Calculate(i) slip(ii) rotor copper loss(iii) total power input if the stator losses are 2500 Watts| (iv) efficiency(v) line current(d) The armature and field resistances of a 300 V, de shunt motor are 0.6 2 and 260 2 respectively. When drivinga load of constant torque at 600 rpm, the armature current is 25 A. If it is required to increase the speed from 600rpm to 750 rpm, calculate the resistance to be connected in the shunt field circuit.

(b): Given in the question: Turns ratio: N1N2=101 Voltage on the primary side is: V1 = 2400V Voltage…

b) A single-phase transformer with 10: 1 turns-ratio and rated at 50 kVA, 2400-V/240-V, 50-Hz is used to step down the voltage of a distribution system. The low tension (LT) voltage is to be kept constant at 240 V. Find the value of the load impedance of the LT side so that the transformer is loaded fully. Find also the value of the maximum flux inside the core if the LT side has 23 turns.

b) A single-phase transformer with 10: 1 turns-ratio and rated at 50 kVA, 2400-V/240-V, 50-Hz is used to step down the voltage of a distribution system. The low tension (LT) voltage is to be kept constant at 240 V. Find the value of the load impedance of the LT side so that the transformer is loaded fully. Find also the value of the maximum flux inside the core if the LT side has 23 turns.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.9P

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Similar questions

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