1. A 690-V, six-pole A-connected induction motor runs at 1085 rpm when operating at a full load. Assume the friction and windage losses are 2.9 kW and core losses are 3.1kW. the motor paramet are: R₁ = 0.06 Ohm, R2 = 0.05 Ohm, X₁ = 0.21 Ohm, X₂ = 0.19 Ohm, Xm = 18.5 Ohm. a. Find the speed of the motor in both rpm and rad/sec. b. Find the air-gap power. c. Find the motor efficiency. 2. For the motor of problem 1 (top problem), find the following: a. Find the maximum torque and the slip in which it happens. What is the rotor speed at th slip in rpm? b. Find the start-up torque. c. Find the rotor resistance which would result in maximum torque occurring at the rotor

1. A 690-V, six-pole A-connected induction motor runs at 1085 rpm when operating at a full load. Assume the friction and windage losses are 2.9 kW and core losses are 3.1kW. the motor paramet are: R₁ = 0.06 Ohm, R2 = 0.05 Ohm, X₁ = 0.21 Ohm, X₂ = 0.19 Ohm, Xm = 18.5 Ohm. a. Find the speed of the motor in both rpm and rad/sec. b. Find the air-gap power. c. Find the motor efficiency. 2. For the motor of problem 1 (top problem), find the following: a. Find the maximum torque and the slip in which it happens. What is the rotor speed at th slip in rpm? b. Find the start-up torque. c. Find the rotor resistance which would result in maximum torque occurring at the rotor

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 28RQ: What are the advantages and disadvantages of using the following types of motors? shaded-pole...

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