Please show a complete solution to the problem A three-phase,50-Hz, 480-V system supplies the following loads:  A six-pole, 50-Hz, 390-hp, three-phase, wye-connected induction motor, operating at 77 percent of the rated load with an efficiency of 95.1 percent and a power factor of 88.3 percent. 2. A 40-kW, delta-connected, three-phase resistance heater. 3. A 360-hp, 50-Hz, four-pole, wye-connected, cylindrical-rotor synchronous motor, operating at 48 percent of the rated load, with a torque angle of -17.7º. Neglecting copper losses, the synchronous motor is operating at 92.0 percent efficiency, and its synchronous reactance is 0.748 Ohm/phase. Determine the active power of the system in watts. Give your final answer in 2 decimal places.

Please show a complete solution to the problem A three-phase,50-Hz, 480-V system supplies the following loads:  A six-pole, 50-Hz, 390-hp, three-phase, wye-connected induction motor, operating at 77 percent of the rated load with an efficiency of 95.1 percent and a power factor of 88.3 percent. 2. A 40-kW, delta-connected, three-phase resistance heater. 3. A 360-hp, 50-Hz, four-pole, wye-connected, cylindrical-rotor synchronous motor, operating at 48 percent of the rated load, with a torque angle of -17.7º. Neglecting copper losses, the synchronous motor is operating at 92.0 percent efficiency, and its synchronous reactance is 0.748 Ohm/phase. Determine the active power of the system in watts. Give your final answer in 2 decimal places.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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Needed to be solve In 20 minutes please
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2) A large 3-phase, 4000 Va (phase to phase), 60 Hz squirrel-cage induction motor draws a current of 385 A/phase. The total active power at the stator input terminals is 2344 kW, when operating at full load. The corresponding speed is accurately measured and found to be 709.2 r/min. The stator is connected in wye and the resistance between two stator terminals is 0.10 Q. The total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate the following: a) The power factor at full load b) The active power supplied to the rotor c) The total 12.R losses in the rotor d) The load mechanical power (kW), torque (kN-m), and efficiency. S = Va• V3- I S= Vy 3•I %3D
Electrical and electronic engineering
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