A part of an industrial plant has the following motor loads. • Two 5 MW, 11 kV, 8-pole, 0.85 leading power factor synchronous motors. • • Two 2 MW, 6.6 kV, 730 rpm, 0.89 lagging power factor, wound-rotor induction motors. Two 1 MW, 3.3 kV, 735 rpm, 0.87 lagging power factor wound-rotor induction motors. • Four 500 kW, 400 V, 1470 rpm, 088 lagging power factor squirrel-cage induction motors. • Ten 100 HP, 400 V, 1484 rpm, 0.88 lagging power factor squirrel-cage induction motors. Twenty 20 HP, 400 V, 1460 rpm, 0.86 lagging power factor squirrel-cage induction motors. • • Single-phase loads such as lighting, office fans, computers, etc totaling 20 kW. The plant is fed by a double-circuit 66 kV overhead line which terminates on the 66 kV bus bar in the main substation of the plant. You are required to select suitable transformers to supply the motor loads described above. Your selection should include the following: • Power rating of each transformer. • Voltage transformation ratio of each transformer.

A part of an industrial plant has the following motor loads. • Two 5 MW, 11 kV, 8-pole, 0.85 leading power factor synchronous motors. • • Two 2 MW, 6.6 kV, 730 rpm, 0.89 lagging power factor, wound-rotor induction motors. Two 1 MW, 3.3 kV, 735 rpm, 0.87 lagging power factor wound-rotor induction motors. • Four 500 kW, 400 V, 1470 rpm, 088 lagging power factor squirrel-cage induction motors. • Ten 100 HP, 400 V, 1484 rpm, 0.88 lagging power factor squirrel-cage induction motors. Twenty 20 HP, 400 V, 1460 rpm, 0.86 lagging power factor squirrel-cage induction motors. • • Single-phase loads such as lighting, office fans, computers, etc totaling 20 kW. The plant is fed by a double-circuit 66 kV overhead line which terminates on the 66 kV bus bar in the main substation of the plant. You are required to select suitable transformers to supply the motor loads described above. Your selection should include the following: • Power rating of each transformer. • Voltage transformation ratio of each transformer.

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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