Schrage motors variable speed ac motors electric motors. A novel induction machine with continuous speed control is found possible. As with the stator, also the rotor core consists of electrically laminated steel sheets. Below is the electrical drives mcq test that checks your basic knowledge of the electrical drives. Schrage of sweden combined elegantly a srim wrim and a frequency converter into a single unit. In this video i have explained what is schrage motor. A type of alternatingcurrent commutator motor whose speed is controlled by varying the position of sets of brushes on the commutator. The woundrotor secondary is on the stator, with brushes located on the comutator 120 apart exciting the stator.
Switching transient phenomena of schrage motor, electrical. Depending on the phase angle of injected voltage, power factor can be improved. Switching transient phenomena of schrage motor switching transient phenomena of schrage motor kamatani, masahiko. It is a rotor fed induction motor built for speed and power factor control. A new method for impedance control of induction motor speed. Use the link below to share a fulltext version of this article with your friends and colleagues. Daniel schrage studies electroencephalography, circuits and systems, and entropy. Electrical machines ii question bank 2 download pdf. Family owned and operated, and located in java center, ny, conroy motors has been serving the community since 1880. Schrage motor and outline of synchronizing phenomena in principle, the schrage motor can be operated at an arbitrary speed, higher or lower than the synchronous speed, by changing the brush angle.
A schrage motor is a polyphase commutator motor with shunt characteristic, in which the rotor carries two windings, of which one receives current from the supply by means of collector rings, while the other is connected to the commutator. It is a variable speed commutator type 3 phase shunt type, brush shifting induction motor, and was invented in 1911 by h. If the capacitor of a singlephase motor is shortcircuited the motor will not start the motor will. Oct 14, 2009 the schrage motor is a variable speed motor that was commonly used in applications related to yarn and carpet making. Induction motor action occurs between primary and secondary windings. Schrage motor is basically an inverted polyphase induction motor, with primary winding on the rotor and secondary winding on the stator. Synchronizing phenomena of schrage motors at synchronous. Schrage motors electrical calculations and induction motor. Working of schrage motor 942015s5 6 primary energized with line frequency voltage. Vector diagrams showing voltage relationships at sub synchronous speed and above synchronous. Unlimited viewing of the articlechapter pdf and any associated supplements and figures.
A relation between the torque and the primary leakage reactance of the schrage commutator motor is pointed out and it has been. Single phase 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. Schrage of sweden combined elegantly a srim wrim and a frequency. Mo tor motor characteristicscharacteri5tics of series mo. It was developed in sweden, but is not commonly used today. Unlike induction motor the primary winding of schrage motor is on the rotor. Speed control of schrage motor is possible by varying the injected emf into the motor which can be controlled by changing the angular. In this volume in the mit presss essential knowledge series, innovation expert michael schrage explains the origins, technologies, business applications, and increasing societal impact of recommendation engines, the systems that allow companies worldwide to know what products, services, and experiences you might also like. Three phase supply is given to the primary with the help of 3 slip rings. Donald schrage will be referred to by name, respondent or as the former husband.
High step count motors topout at lower rpms than similar size. Pdf doubly fed induction motors kimbugwe simon peter. View the article pdf and any associated supplements and figures for a period of 48 hours. Single phase induction motor multiple choice questions. Which of the following motor is a constant speed motor. Torque versus power factor curve for a schrage motor. By far the most commonly used ac motor is the induction motor. Schrage motorsis a combination of a wound rotor induction motor and frequency convertor.
In capacitor start singlephase motors current in the starting winding leads the voltage current in the starting winding lags the voltage current in the starting winding is in phase with voltage in running winding none of the above answer. Polyphase commutator motors with shunt characteristics core. The rotor also carries a lowvoltage commutator winding with conductors located in the same slots as, and above, those of the primary. The ac variable speed commutator motor is essentially a 3 phaseinduction motor with an e. On the rotor, there is a three phase delta winding with the endpoints of the delta brought out on to slip rings. Jul 29, 2016 schrage motors my avatar my thanks go to rapparee for the photographs of a rather poorly schrage motor. A pony motor is used for the starting which of the following motors. In the neighborhood of synchronous speed, however, an abnormal phenomenon occurs when the motor is.
Schrage motor operation principle and characteristics of schrage. Apr 28, 2017 download any book for free pdf,free books download pdf, free pdf books bestsellers, free ebooks download for android, download free books by isbn number, free ebook download sites without registration, free books online pdf, where to download free ebooks,history books in urdu free download pdf,islamic urdu books pdf free download, urdu library free download. Schrage motor can be treated as an inverted poly phase induction motor. Theory of arc interruption and different types of oil circuit breakers. The motor can be treated as an inverted poly phase induction motor. Induction motor which has built in arrangement both for speed control. Transformer action occurs between primary and regulating windings. Same is an inverted induction motor with slip regulator. Schrage motor is an ac commutator machine schrage motor is basically an inverted polyphase induction motor.
A relation between the torque and the primary leakage reactance of the schrage commutator motor is pointed out and it has been shown that an increase in this primary reactance results in an extension of the supersynchronous. It provides indepth discussion on construction, working principles and applications of various electrical machines. Single phase induction motor quiz single phase induction. It is also called the inverted poly phase induction motor. Reliable equations of performance are derived for the schrage motor by the use of tensor calculus. Operation, characteristic, applications magnetic levitation. If resultant rotor voltage increases, current increases, torque increases and speed increases. It is a rotor fed, shunt type, brush shifting, 3 o. You have to select the right answer to the question. This electrical drives mcq test contains 20 multiple choice questions. Each circle is related to a certain brush separation and a certain brush shift, which control respectively the speed and the power factor of the motor. The expressions for torque, slip and current in terms of this angle are derived and are discussed with the aid of. It is a rotor fed, shunt type, brush shifting, 3 o commutator induction motor.
Polyphase commutator motors with shunt characteristics. This final thesis will mostly be dedicated to induction motors but also to synchronous permanent magnet and reluctance motors. The symbol a will refer to the attached appendix and ea will mean emphasis added. This design was demonstrated on a theoretical coaxial helicopter. Free download in pdf single phase induction motor multiple choice questions with answers for competitive exams. The primary excitation winding of the motor is located on the rotor reverse of a woundrotor motor and is excited through sliprings. Schrage motor has three windings two in rotor and one in stator. In an three phase induction motor where both stator and rotor are wound, each with a three phase winding, and the rotor equipped with three slip rings, then when the stator winding are fed with a three phase supply and the rotor slip rings loaded. It is a rotor fed, shunt type, brush shifting, 3 o commutator induction motor which has built in arrangement both for speed control and p.
The primary winding on the rotor is fed through three slip rings and brushes at line frequency. The schrage motor is a commutator induction motor which combines speed control and power factor improvement facilities. Schrage motor is essentially a combination of wound rotor induction motor and frequency convertor. Like never before schrage motor has been discussed. Schrage motor article about schrage motor by the free. Feb 17, 2020 resolution is often expressed as degrees per step. The tradeoff for high resolution is speed and torque. Feb 05, 2020 electrical machines by sk sahdev covers the fundamental concepts of electrical machines, highlighting transformers, motors, generators and magnetic circuits. Schrage motor induction motors gate ies nikhil nakka. An induction motor also known as an asynchronous motor is a commonly used ac electric motor.
Sep 04, 2015 working of schrage motor 942015s5 6 primary energized with line frequency voltage. And the higher steprates needed to turn these motors results in lower torque than a similar size lowstepcount motor. This unwanted induced current is also called eddy current. Which of the following is the disadvantage of rotor resistance control. These short solved questions or quizzes are provided by gkseries. Torque analysis of the schrage commutator motor sciencedirect. Characteristics of schrage motor at brush shift angle.
From these equations the centres and radii of the circle diagrams are established. A text book of electrical technology bl theraja volume2. The circle diagrams are often totally unreliable owing chiefly. Schrage motor operation principle and characteristics of. Electrical machines ii question bank download pdf electrical machines ii important questions download pdf electrical machines ii 2 marks with answers download pdf. Kamatani metropolitan college of technology, tokyo 1. Single phase induction motor, theory of operation double. Finally, you can also attempt online quiz from the take electrical drives quiz button.
Motor principlecomparison of generator and motor ac lionsignificance of the bad emfvoltage equation of a motor conditions for maximum ture torque of a motor shaft of a d. It is a rotor fed, shunt type, brush shifting, 3 o commutatorinduction motor. An electric motor is an electrical machine that converts electrical energy into mechanical. The schrage motor has its primary winding on the rotor, connected to the supply through sliprings and brushes. It is a rotorfed shunt type brush shifting 3 phase induction motor which has built in arrangement for speed control and power factor improvement.
Reliable equations of performance for the schrage motor are deduced in terms of the angle between the stator and the rotor magnetomotive force waves, resulting in an original treatment. In this brief, carlie cargile schrage will be referred to by proper name or as petitioner or the former wife. There are two types of induction motors, one with wound type rotor, also called slipring motor and another one with squirrelcage rotor. A schrage motor is essentially a combination of a wound rotor induction motor and a frequency converter. These short objective type questions with answers are very important for board exams as well as competitive exams. The commutator with the lap winding is in parallel with an induction motor and this has necessitated the machine to be rotorfed. The schrage motor speed can be controlled by varying the injected electromagnetic field emf into the motor. The schrage motor is a variable speed motor that was commonly used in applications related to yarn and carpet making. The same speedcontrolled motor was also produced in the usa as the bta brushshifting motor. The expressions for torque, slip and current in terms of this angle are derived and are discussed with the aid of graphs and locus diagrams. The speed and power factor of slip ring induction motor can be controlled by injecting slip frequency voltage in the rotor circuit. Electrical machines ii ee8401, ee6504 anna university.
Scharge motor 942015s5 2 it is a rotor fed, shunt type, brush shifting, 3 o commutator it has built in arrangement. Schrage motors schrage motors talk electrician forum. This motor may be regarded as an inverted version of a schrage motor in. Schrage motor three winding motor primary, secondary. A type of alternatingcurrent commutator motor whose speed is controlled by varying the position of. The equations and circle diagrams of the schrage motor. This special feature of the machine has given it a shunt characteristic. An electrical motor is a device that has brought about one of the biggest advancements in the fields of engineering and technology ever since the invention.
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