Polyphase induction motors mcqs answers pdf electrical engg. Us5214366a threephase converter for polyphase induction. Common highway engineering civil engineering objective type questions and answers pdf. Polyphase induction motors for power generating stations.
Therefore it will be essential for you to distinguish. Click download or read online button to get asynchronous machines book now. Download free ebooks home engineering mechanical engg. The first ac commutatorfree threephase induction motors were independently invented by. It is simple and relatively inexpensive, and the absence of sliding contacts in the squirrelcage machine reduces maintenance to a minimum.
By order of the executive director office of the federal register washington, d. Ieee std 1122004 revision of ieee std 1121996 ieee standard test procedure for polyphase induction motors and generators sponsor electric. In an induction motor,esecondarg structure comprising a. Feb 12, 2017 it is a motor, that works only with 3 phases or harmonics of 3, where application of voltage induces a rotating magnetic field or rather, the varying values of voltage values make it seem like the field is rotating, which causes a shorted roto. In fact, 90% of industrial motors are induction motors. The polyphase induction motor is the most commonly used industrial motor. Record all nameplate information for the induction motor. Remember that you are working with polyphase power. Drfoc of polyphase induction motor based on fuzzy logic controller speed. Principle of operation of single phase induction motor. Objective polyphase induction motors questions and answers pdf. A polyphase induction machine operated by an inverter drive system.
Starting methods for polyphase induction machine february 17, 2019 february 24, 2012 by electrical4u in this article we are going to discuss various methods of starting a 3 phase induction motor. Test procedure for polyphase induction motors and generators. The national electrical manufacturers association nema released a new energy management guide for polyphase induction motors. This book places emphasis on practice through the use of extensive modeling, simulation and analysis to. In this study an equivalent circuit is proposed that permits the analysis of, or even the calculation for, singlephase, twophase and threephase induction motors. Polyphase induction motor definition of polyphase induction. Home electrical engineering multiple choice questions 110 top most polyphase induction motors electrical engineering multiple choice questions and answers. Determination of the losses in induction machines due to harmonics pdf. Test procedure for polyphase induction motors and generators name of standards organization.
There are two general types of polyphase induction motors. We classify starting methods for squirrel cage induction motor into two types on the basis of voltage. Us6054837a polyphase induction electrical rotating. Other readers will always be interested in your opinion of the books youve read. It has been shown in chapter 1 that the polyphase induction motor can be considered as a polyphase transformer with variable frequency in the shortcircuited secondary winding and an equivalent circuit can be derived per phase of the motor in the same general way as that of a transformer. Request pdf equivalent circuit for a polyphase induction motor in this study an equivalent circuit is proposed that permits the analysis of, or even the calculation for, singlephase, two. Here basic operation principle of an induction motor is. It is a motor, that works only with 3 phases or harmonics of 3, where application of voltage induces a rotating magnetic field or rather, the varying values of voltage values make it seem like the field is rotating, which causes a shorted roto. A threephase converter for polyphase induction motors has an input transformer with primary windings and at least two secondary windings associated with each primary winding, and controlled power semiconductors. Isbn 07389785 ss95211 no part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. The threephase induction motor is the extensively used for various kinds of industrial drives.
An induction motor or asynchronous motor is an ac electric motor in which the electric current. Design, and application electrical and computer engineering cochran, paul on. Home interview questions on polyphase induction motors electrical engineering realtime polyphase induction motors multiple choice questions and answers pdf realtime polyphase induction motors multiple choice questions and answers pdf. Starting of 3 phase induction motors, high starting torque motors. Tesla polyphase induction motors ac motors electronics. Problems and premature failures often indicate input power system troubles, poor or deteriorating mechanical installations, or malfunctions in the driven machinery. Thermodynamics questions and answers pdf free download 1. Polyphase induction motors quiz questions and answers. The 3phase set of currents, each of equal magnitude and with a phase.
Polyphase induction motors, analysis by paul cochran. Our polyphase squirrel cage induction motors are designed for across the line or increment starting as required. The electric energy generated purchased by consumers for different needs. In the drawing, a represents the primary winding of the motor. Dol starting of induction motors is usually restricted to a low horsepower motors b variable speed motors. Ieee std 1122004 ieee standard test procedure for polyphase induction motors and generators. This standard covers instructions for conducting and reporting the more generally applicable and acceptable tests of polyphase induction motors and generators. Institute of electrical and electronics engineers legally binding document. Therefore, motor troubleshooting involves the entire system, not just the. Cage induction motor an overview sciencedirect topics. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. Polyphase motor design polyphase ac circuits electronics.
Dawns little brother jeff is visiting the new schaferspier family. The book covers topics such as the modeling of steadystate motor performance polyphase induction, synchronous, and a. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. Ac motors polyphase peerless electric designs 3phase motors from 120 to 50 hp in various frame sizes from 4. Working of 3 phase induction motor is explained in this video with help of animation. Various methods of speed control 3phase induction motor. Which of the following variables controls the physical properties of a perfect. Motor wg112 motor sc test procedure for polyphase induction motors and generators. Design, and application electrical and computer engineering.
Nema mg 102017 energy management guide for selection and use of fixed frequency medium ac squirrelcage polyphase induction motors. Polyphase induction motors electrical engineering questions. Polyphase induction motor definition is an alternatingcurrent motor having polyphase as 3phase windings. Asynchronous machines download ebook pdf, epub, tuebl, mobi. The basic idea of an electric motor is to generate two magnetic fields. Equivalent circuit for a polyphase induction motor request pdf. Most asked objective questions or mcq on polyphase induction motors electrical engineering. Home most asked objective questions or mcq on polyphase induction motors electrical engineering latest polyphase induction motors multiple choice questions and answers pdf. Realtime polyphase induction motors multiple choice questions.
Us6054837a polyphase induction electrical rotating machine. Polyphase power is particularly useful in ac motors, such as the induction motor, where it generates a rotating magnetic field. The rotor of a polyphase induction machine may be one of two types. Which of the following component is usually fabricated out of silicon steel. Practicing all polyphase induction motors electrical engineering questions and answers in online helps you to improve your ability to attend the real time gate, ies and bsnl jto exams. This site is like a library, use search box in the widget to get ebook that you want. The squirrelcage motor is the simplest to manufacture and the easiest to maintain. Objective polyphase induction motors questions and answers pdf 71.
The polyphase current produces a rotating magnetic. Ac induction motors are also the most common motors used in main powered home appliances. Squirrelcage induction motor the operation of the squirrelcage motor is simple. Ieee std 1122004, ieee standard test procedure for. Latest polyphase induction motors multiple choice questions and answers pdf. An induction motors rotor can be either wound type or squirrelcage type.
Instructions for conducting and reporting the more generally applicable and acceptable tests of polyphase induction motors and generators are covered. Ieee standard test procedure for polyphase induction motors. The frame of an induction motor is usually made of a silicon steel b cast iron. An induction motor or asynchronous motor is an ac electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. Threephase cage induction motors are the most widely used for ancillary. You should also make a dc measurement of stator winding linetoline resistance using a dmm. An induction motor can therefore be made without electrical connections to the rotor. Home category electrical engineering mcq questions and answers 3 phase induction motors 1 the frequency of the induced emf in an induction motor is a. Pdf drfoc of polyphase induction motor based on fuzzy logic.
Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. Polyphase induction motor mcq set 03 objectivebooks. A 3 phase induction motor can be used for different applications with various speed and load requirements. In rheostatic braking, the stator winding is employed as a dc field winding and the rotor winding as an armature winding. Pdf polyphase induction machines nasrin shaheen academia. On the other hand, the polyphase induction motor shown in cutaway in fig. Polyphase induction motors for power generating stations part i.
Whether youve loved the book or not, if you give your honest and detailed thoughts then people will find new books that are right for them. Jul 02, 20 working of 3 phase induction motor is explained in this video with help of animation. In a threephase induction motor, the number of poles in the rotor winding is always a zero b more than the number of poles in stator c less than number of poles in stator d equal to number of poles in stator ans. The polyphase induction motor the polyphase induction motor is the most commonly used industrial motor, finding application in many situations where speed regulation is not essential. Nema publishes energy management guide for polyphase. Polyphase induction motors mcqs answers pdf electrical. Perhaps the most important benefit of polyphase ac power over singlephase is the design and operation of ac motors.
Ieee std 1122004, ieee standard test procedure for polyphase. He is miserable because all his old friends have changed, and. The motor is mounted in a test rig that allows one to control the torque applied to the motor shaft and to measure both rpm and torque. S bimbhra pdf download free if you are finding the electrical machine by ps bimbhra pdf then this is the right place for you. Induction motors are favored due to their ruggedness and simplicity.
The guide includes practical information about the proper selection, installation. Equivalent circuit for a polyphase induction motor. The most common type of motor in this group is the squirrelcage polyphase induction motor so called because the rotor is constructed like a squirrelcage fig. As we studied in the first chapter of this book, some types of ac motors are virtually identical in construction to their alternator generator counterparts, consisting of stationary wire windings and a rotating magnet assembly. Download as ppt, pdf, txt or read online from scribd. Krishnan electronic control of machines develops a systematic approach to motor drives.
Home mcq polyphase ind motors polyphase induction motor mcq set 03 polyphase induction motor mcq set 03. Sep 02, 2014 101 top polyphase induction motors electrical engineering multiple choice questions and answers. Polyphase induction motors mcq question is the important chapter for a electrical engineering and gate students. We use cookies to make interactions with our website easy and meaningful, to better understand the use of our services, and to tailor advertising.
S bimbhra pdf download free if you are finding the electrical machine by ps bimbhra pdf then this is the right plac. If an induction motor with certain ratio of rotor to stator. Polyphase induction motors mcqs answers electrical engineering multiple choice questions answers pdf download. Electrical braking in polyphase induction motors electrical. Nikola tesla conceived the basic principles of the polyphase induction motor in 1883 and had a half horsepower 400 watts model by 1888. Starting methods for polyphase induction machine electrical4u. Ieee standard test procedure for polyphase induction. The rotor will constantly be turning to align its magnetic field with that of the stator field. Twelve or more phases are used to sufficiently cover the airgap region, in contrast to the conventional three phases using distributed and chorded windings. Many of the tests described may be applied to both motors and generators, as needed, and no attempt is made to partition the test procedure into clauses and subclauses that separately apply to motors or to generators.
A 3phase induction motor stator delta connected, is carrying full load and one of its fuses blows out. Polyphase induction motors, electrical engineering multiple choice questions objective type questions, mcqs, with question and answers, download free pdf, electrical engineering, multiple choice questions, objective type questions, electrical engineering short notes, rapid fire notes, best theory. The rheostatic braking with a polyphase induction motor can be obtained by disconnecting the stator winding from the ac supply and exciting it from a dc source to produce a stationary dc field. The advantages of threephase ac induction motor are listed below. The machine is constructed with concentrated full span windings. Teslas polyphase system and induction motor 125 understand why the motor does not have the highest torque at start, and because of the second mistake he came to the wrong conclusion that that motor can not have the efficiency higher than 0. The induction motor is made up of the stator, or stationary windings, and the rotor.