•The rotor impedance at standstill of a three-phase, Y-connected, 208-V, 60Hz, 8-pole, wound-rotor induction motor is...

•The rotor impedance at standstill of a three-phase, Y-connected, 208-V, 60Hz, 8-pole, wound-rotor induction motor is 0.1 + j0.5 Ω/phase. •Determine the breakdown slip, (0.2) the breakdown (maximum) torque, (458.37 Nm) and the power developed by the motor at maximum torque (34.6kW). •What is the starting torque of this motor? (176.3 Nm) •Determine the resistance that must be inserted in series with the rotor circuit so that the starting torque is 50% of the maximum torque. (0.034Ω)

Expert Solution

Manojponduru answered 1 month ago

The parameters of a 3-phase, 4-pole, 50 Hz, Y-connected, wound-rotor induction motor are listed below. These...

The parameters of a 3-phase, 4-pole, 50 Hz, Y-connected, wound-rotor induction motor are listed below. These are the default values of the “Asynchronous Machine” model in MATLAB Simulink. r1=0.5968 ?; r2=0.6258 ?; L1=0.0003495 H; L2=0.005473 H; Lm=0.0354 H; Stator line voltage = 400 V rms. The motor for rotor speeds nm= 0 to 1500 rpm. X1= 0.1097 ohm, X2= 1.719 ohm , Xm= 11.12 ohm, RTH = 0.5853 , XTH = 0.1395 and VTH = 230.82 V. Suppose the motor...

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A Y- connected, 460- V, 1710- rpm, 60- Hz, 4- pole squirrel cage induction motor has a rotor current at starting 6 times the rotor current at full load. Calculate: a. The starting torque as percent of full load torque. b. The slip and speed at which the motor develops maximum torque. c. The maximum torque developed b the motor as percent of its full load value.

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