Problem 7 A three-phase, 60 Hz, six-pole, Y-connected, 480-V induction motor has the following parameters: R₁ = 0.20, R2 = 0.102, Xeq = 50 The load of the motor is a drilling machine. At 1150 rpm, the load torque is 150Nm. The motor is driven by a constant v/f technique. When the frequency of the supply voltage is reduced to 50 Hz, calculate the following: a. Motor speed b. Maximum torque at 60 Hz and 50 Hz c. Motor current at 50 Hz Hint: For a drilling-machine load (an inverse-speed-characteristics load) T₁/T₂ = n2/n1 = (1-S₂)/(1-1)

Problem 7 A three-phase, 60 Hz, six-pole, Y-connected, 480-V induction motor has the following parameters: R₁ = 0.20, R2 = 0.102, Xeq = 50 The load of the motor is a drilling machine. At 1150 rpm, the load torque is 150Nm. The motor is driven by a constant v/f technique. When the frequency of the supply voltage is reduced to 50 Hz, calculate the following: a. Motor speed b. Maximum torque at 60 Hz and 50 Hz c. Motor current at 50 Hz Hint: For a drilling-machine load (an inverse-speed-characteristics load) T₁/T₂ = n2/n1 = (1-S₂)/(1-1)

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

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.4P

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Similar questions

Name three factors that determine the torque produced by an induction motor.
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