The nameplate of a 3-phase asynchronous motor is represented by the below figure The motor operates at full load under a voltage of U-380V (between phases). The stator Joule's losses are P₁, 100 W and the stator iron losses are P₁-50 W. a) Determine the type of connection of the stator windings. b) Determine the number of poles (2p) and the synchronous speed (n.). c) Calculate the slip (s). d) Calculate the absorbed power (P₁). e) Show that the efficiency is n = 76%. f) Calculate the power transmitted to the rotor (P). g) Calculate the rotor Joule's losses (P). h) Calculate the mechanical losses of the motor. Pu f

The nameplate of a 3-phase asynchronous motor is represented by the below figure The motor operates at full load under a voltage of U-380V (between phases). The stator Joule's losses are P₁, 100 W and the stator iron losses are P₁-50 W. a) Determine the type of connection of the stator windings. b) Determine the number of poles (2p) and the synchronous speed (n.). c) Calculate the slip (s). d) Calculate the absorbed power (P₁). e) Show that the efficiency is n = 76%. f) Calculate the power transmitted to the rotor (P). g) Calculate the rotor Joule's losses (P). h) Calculate the mechanical losses of the motor. Pu f

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 12.6P

See similar textbooks

Similar questions

Induction motors and welding transformers require magnetizing current, which causes a. lagging power factor. b. leading power factor. c. unity power factor. d. zero power factor.
a)the figure below shows the per-phase equivalent circuit of a two - pole three- phase induction motor operating at 50 Hz . The voltage (E1) across the magnetizing inductance is 210 v , and the slip (s) is 0.05 . What is the developed torque produced by the motor ? b) A 4 poles , 50Hz , Y-connected three phase induction motor has the per phase equivalent circuit parameters of (R1 =R2=0.12 , X1=X2=0.6 , Xm =12 ) ohm and I2 =20 (0 . Use exact equivalent circuit to determine the following at rated slip of 0.03 : I. Stator current II. Magnetizing current III. Power factor IV. Developed torque C) What is the physical meaning for each of the following induction motor parameters : R1 , R2 , Rc , X1 , X2 , Xm d) What is synchronous watt
E-a). The lower the speed setting, the_________ the impedance of run winding in a single-phase multi-speed motor. a) lower b) higher c) either "a" or "b" d) neither "a" nor "b" E-b)The rotor of a single-phase repulsion motor gets its voltage a) by induction b) direct wired from an external AC source c) direct wired from an external DC source d) all of the above
Q11-b) A three-phase induction motor is used to drive many types of loads for example water pump and compressor. Explain the followings: i. The construction and its operational principle;ii. Synchronous speed, rotor speed, slip and their relationships,iii. Starting methods for induction motor,iv. Disadvantages of induction motor.
A 460V, 25hp, 60Hz, 4 pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R1 = 0.641 Ω R2 = 0.332 Ω X1 = 1.106 Ω X2 = 0.436 Ω Xm = 26.3 Ω The total rotational losses are 1100W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 3.5% at the rated voltage and rated frequency, find the motor’s Speed Stator current Power factor Pconv and Pout Ʈǐnd and Ʈload Efficiency
A 3-phase, 6 pole, 440 V, 60 Hz, Y-connected induction motor has the following impedances per phase referred to the stator circuit: R1=0.43 Ω, R2=0.54 Ω, X1=1.263 Ω, X2=0.608 Ω, XM=43Ω The total rotational losses are 1100 W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 2 percent at the rated voltage and rated frequency, Find the motor speed, stator current, output power
A delta connected 1185 V, 50 Hz three phase induction motor has a star-connected slip-ring rotor with a phase transformation ratio of 4. 2. The per phase rotor resistance and standstill leakage reactance are 0.0627 ohm and 0.049 ohm respectively. Assuming the stator impedance and magnetizing current are neglected. Calculate the the following iii) The rotor current at 3 % slip with slip-rings are short circuited. (iv) The rotor power factor at 3 % slip with slip-rings are shot (v) The external rotor resistance per phase required to obtain a starting current of 145 A in the stator supply lines.
A synchronous, three-phase motor, connected in Y, with a frequency of 60Hz, 2300V, has a synchronous reactance of 110 per phase. The synchronous motor is a smooth pole motor. When delivering 200HP, the efficiency is calculated to be 90%, neglecting losses in the magnetic field. The power factor angle is 15 electrical degrees. Also neglect the ohmic resistance of the windings and calculate: a) The induced excitation voltage per phase. b) The line current. c) The power factor of the synchronous motor.
QI: The parameters of a 4 kW, 220V. 2-phase induction motor, in ohms per phase, are: r1=0.53, x1 =2.4, XM= 70, r2 = 0.96, x2 = 3.0. The motor is operated from unbalanced 2- phase source whose voltages are 230V and 210V, the smaller voltage is lagging the larger by 800. For a slip of 5% and rotational losses of 30 W, find the positive- and negative- sequence components of: (a) the applied voltages. (b) Find the values of phase currents (c) the input current. (d) Find the developed mechanical power. (e) Find the efficiency.
A 3-phase induction motor having a synchronous speed of 1200 rpm draws 70kW from a 3-phase feeder.The copper losses and iron losses in the stator amount to 4kW.Friction and windage losses amount to 2kW.If the motor runs at 1170 rpm, determine the a. active power transmitted to the rotorb. rotor copper lossesc. mechanical power developedd. the mechanical power delivered to the loade. efficiency of the motor.
The result of no-load test on a 3-phase Y-connected induction motor are as follows: line to line voltage =400v; input power= 1770W; input current =18.5A; friction and windage loss = 600W. Determine:1. resistance per phase representing the core loss2. the magnetizing reactance per phase of the core.
A three-phase induction motor with electrical phase equivalent circuit below is 4 poles and the label rotor speed is It is 1455 rpm. Wind-friction and iron losses are neglected. The motor is delta connected. a.) Calculate the development moment. b.) Calculate the overturning moment. c.) Calculate the value of the line current at the stator development moment (t = 0 s). d.) If Y / ∆ is started to this motor, what will be the value of the line current at the moment of development (t = 0 s).