A 440-V, 3-φ 50-Hz, 4 poles, 37.3 kW, Y-connected induction motor has the following parameters: R1=...

A 440-V, 3-φ 50-Hz, 4 poles, 37.3 kW, Y-connected induction motor has the following parameters:

R1= 0.1 Ω, X1 = 0.4 Ω , R2′ = 0.15 Ω , X2′ = 0.44 Ω

Motor has stator core loss of 1250 W and rotational loss of 1000 W. It draws a no-load line current of 20 A at a p.f. of 0.09 (lag). When motor operates at a slip of 3%, calculate

a. input line current and p.f. [57.4@29°A, 0.875 lag]

b. electromagnetic torque developed in N-m [230 Nm]

c. output and [34075 W]

d. efficiency of the motor. [88.7%]

Expert Solution

Manojponduru answered 11 months ago

A 50-Hz, 440-V, 2 pole wye connected induction motor is rated at 75 kW. The equivalent...

A 50-Hz, 440-V, 2 pole wye connected induction motor is rated at 75 kW. The equivalent parameters are as follows: RS = 0.075 Ω RR’ = 0.065 Ω XS = XR’ = 0.17 Ω Xm = 7.2 Ω The losses associated with the machine are field and winding, miscellaneous and core loss with values of 1 kW, 150 W and 1.1 kW, respectively. For a slip of 4 %, determine a) The line current. (150.39  -23.08 A) b) The...

A 50-Hz, 440-V, 6 pole wye connected induction motor is rated at 75 kW. The equivalent...

A 50-Hz, 440-V, 6 pole wye connected induction motor is rated at 75 kW. The equivalent parameters are as follows: RS = 0.082 Ω; RR’ = 0.07 Ω; XS = 0.19 Ω; XR’ = 0.18 Ω; XM = 7.2 Ω The losses associated with the machine are field and winding, miscellaneous and core loss with values of 1.3 kW, 150 W and 1.4 kW, respectively. For a slip of 4 %, determine: a) The line current b) The stator power...

A 3-phase, 380 V, 50 Hz , 6 pole, Y-connected induction motor has R1 = 0.1...

A 3-phase, 380 V, 50 Hz , 6 pole, Y-connected induction motor has R1 = 0.1 W , X1 = 0.4 W, R2’ = 0.12 W , X2’ = 0.4 W, Xm = 20 W , Pr = 1 kW. The motor is operated at 970 rpm what is the efficiency?

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...

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs =...

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs = 0.53 Ω, R’r = 0.38 Ω, Xs = 1.23 Ω, X’r = 1.45 Ω, and Xm = 25.2 Ω. The motor is controlled by varying both the voltage and frequency. The volts/hertz ratio, which corresponds to the rated voltage and rated frequency, is maintained constant. a) Calculate the maximum torque, Tm and the corresponding speed, ꞷm for 60 Hz and 30 Hz. b) Repeat...

A 440 V 4-pole 3 phase 50 Hz slip ring induction motor has its stator winding...

A 440 V 4-pole 3 phase 50 Hz slip ring induction motor has its stator winding mesh connected and its rotor winding star connected. The standstill voltage measured between slip rings with the rotor open –circuited is 218 V. the stator resistance per phase is 0.6Ω and the stator reactance per phase is 3Ω. The rotor resistance per phase is 0.05Ω and the rotor reactance per phase is 0.25Ω. Calculate the maximum torque and the slip at which it occurs....

A 37.3 kW 4 pole 50 Hz induction machine has a friction windage torque of 22...

A 37.3 kW 4 pole 50 Hz induction machine has a friction windage torque of 22 N-m. the stator losses equal the rotor circuit loss. Calculate: The input power to the stator when delivering full-load output at a speed of 1.440 rev/min [44000 W] The gross input and stator output power when running at a speed of 1560 rev/min. the stator losses are as in (a) and the windage and friction torque is unchanged [291 N-m; 40300 W]

Q3) A three-phase, Y-connected, 220 V, 13 kW, 60 Hz, six-pole induction motor has the following...

Q3) A three-phase, Y-connected, 220 V, 13 kW, 60 Hz, six-pole induction motor has the following parameter values in Ω/phase referred to the stator: R1 = 0.3 Ω. R2' = 0.15 Ω X1 = 0.5 Ω. X2'= 0.21 Ω Xm = 13.25 Ω The total rotational losses are 450 W. The core loss is lumped in with the rotational losses. For a slip of 0.02, and based on approximate equivalent circuit, determine: (i) The rotor speed. (ii) The stator current....

A 3 phase 460 V, 60 Hz, 4 pole, delta connected induction motor has the following...

A 3 phase 460 V, 60 Hz, 4 pole, delta connected induction motor has the following equivalent circuit parameters. Rs = 0.42 Ω, Rr = 0.23 Ω, Xs = Xr = 0.82 Ω. Xm = 22 Ω. The no load loss = 60 W and may be assumed constant. The rotor speed is 1750 rpm. Use the approximate equivalent circuit ( i.e. the Xm branch is at the very left of the circuit) determine the following a. the synchronous speed...

A Y- connected, 460- V, 1710- rpm, 60- Hz, 4- pole squirrel cage induction motor has...

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.

Question