A proper starting method is important on the industrial scale motor in order to reduce excessive overcurrent that could jeopardise the winding and insulation in the motor itself. The STAR-DELTA circuit configuration in Figure Q4(b) is the most commonly favourable by industry. (i) Explain how the excessive start-up time and locked rotor current can contribute to overheated condition. (ii) Analyse in brief STAR-DELTA circuit in terms of the principles used when starting the motor, the voltages, resultant currents and torques.

A proper starting method is important on the industrial scale motor in order to reduce excessive overcurrent that could jeopardise the winding and insulation in the motor itself. The STAR-DELTA circuit configuration in Figure Q4(b) is the most commonly favourable by industry. (i) Explain how the excessive start-up time and locked rotor current can contribute to overheated condition. (ii) Analyse in brief STAR-DELTA circuit in terms of the principles used when starting the motor, the voltages, resultant currents and torques.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

1. What is the formula for torque production in a single-phase induction motor? Draw a vector diagram for capacitor start single-phase induction motor.2. Which type of starter is popular for using in induction motor and why?
G-1). The 3-phase squirrel-cage induction motor has a poorer starting torque than might be expected based on the line current being drawn, because the rotor current and stator currents are out of phase as a result of the high rotor frequency at starting. a) true b) false G-2). Which of the following is/are a general method of starting squirrel-cage motors? a) full voltage starting b) reduced voltage starting c) both a" and "b" d) neither "a" nor 'lb" G-3). What is, if any, an objection to building a 3-phase squirrel-cage induction motor with high enough rotor resistance to provide good starting torque? a) stator current would increase b) speed regulation would get poorer c) rotor current would increase d) none of the above G-4). Which code letter(s) is given to the rotor of a 3-phase squirrel cage induction motor with the highest resistive value? a) A b) B-E c) F-V d) none of the above
I need the answer as soon as possible
This questions is about Electrical machines , and I need the answer in 30 minutes please
Q3. (a) For a three-phase squirrel-cage induction motor (SCIM), explain: (i) Why is the motor efficiency relatively low at light and heavy loads? (ii) Under what condition that the motor has the maximum efficiency?
A 3 phase , 6 pole , 400 V , 50 Hz , induction motor has R2= 0.1 ohm /ph , X2= 0.8 ohm /ph and the induced emf between slip rings at standstill is 160 V , Assume the friction losses is 300 W. find :- a) the torque output at slip =3% . b) critical slip and the torque maximum .
g) What is an advantage if the starting Torque of the induction motor is higher than the nominal load Torque? h) What are the main differences when the equivalent circuits of transformer and asynchronous motor are examined?
Q1) A 3-phase, star-connected ,220V,6-poles,induction motor has the following constants: (R1=0.32),(R2=0.15).(X1%3D0.50).(X2=0.22),(Xm=132) the total Friction losses+ core losses are( 1000W), the slip is (0.02) determine : 1-the efficiency, 2- the output torque
Explain the principle of operation, constructional features, and excitation Methods for DC MOTORS AND GENERATORS, Series, Shunt, and Compound
B. What are differences in term of construction and working principle between Shaded Pole Induction Motor and Capacitor Start Induction Motor?
2.b) Explain the speed control of the induction motor with the PWM method. please write it with computer
Q1: Fill in the following blanks: 1. In order to have sparkless commutation, the brushes should be placed along... 2. D.C. series motor are used in those applications where... required. 3. The self-induction of a coil undergoing commutation causes .. . at the brushes. .starting torque is