Construction of three phase induction motor electrical4u. The construction of stator of the induction motor is almost the same as other motors. Mainly we discuss a threephase squirrel cage induction motor. The singlecage and doublecage induction motors formulation is presented in section 3. The squirrel cage induction motor was designed for an extended service life under very demanding conditions. Firstly, i am going to tell you about the structure of squirrel cage induction motor. Squirrel cage type rotor almost 90% of induction motors are squirrel cage motors.
Squirrel cage construction, the rotor winding consists of a number of rotor bars, shortcut by rings from both side, see figure below. Direct starting of squirrelcage induction motors with direct starting, the poles of contactor and motor protective device are connected to the pole conductors figure 1 and the operating current of the motor flows through them. The squirrel cage induction motor is the most commonly used motor in industry. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. Control of motorcharacteristics by squirrelcage rotordesign. May 20, 2015 the threephase induction motor the squirrel cage induction motor the woundrotor induction motor 3 4. Differentiate between the various types of generating electric power stations. Pdf squirrel cage induction motors are very popular in industrial and manufacturing process because of its reliability, low cost and rugged. Harley and yao duan georgia institute of technology november, 2009. Particularly, the squirrel cage type is characterized by its.
Copper rotor the metal chosen for the squirrel cage structure of the induction motor has substantial implications to both motor performance and motor manufacturability. List and describe the more commonly used equipment in an electric substation. A 3 phase induction motor has two types based on the rotor construction, named as. Torquespeed characteristics of three phase squirrel cage. How are squirrel cage induction motors constructed. Procedure for design of a squirrel cage induction motor the following points are to be noted in designing three phase induction motors. Design of squirrel cage induction motor matlab examples. Studying and improving of squirrel cage induction motor scim efficiency is a continuous area of interest not only among the researchers but also the industry, manufacturer and government. In this work a conventional three phase squirrelcage type induction motor with specifications 10 hp, 415v, stardelta connected and 4 poles is chosen for comparison with our motor, which is designed for good efficiency. The proposed procedure for determining the efficiency of the squirrel cage induction motor powered by a vfd allows obtaining the efficiency curves of all the equipment under test and the overall system in a simple and practical way, in order to make a future efficiency rating of the whole induction motor variable frequency drive. Both the types are quite different from each other. A 1phase induction motor is similar to a 3phase squirrel cage induction motor in physical appearance. Recall that leakage reactance is the reactance due to the rotor flux lines that do not also couple with the stator windings. It is low cost and requires low maintenance in comparison with other motor types.
Ac motors can be divided into two main categories 1 synchronous motor and 2 asynchronous motor. Although the emphasis in this work has been placed on the threephase induction motor with a squirrel cage rotor, the same modelling approaches hold for the. The rotor is same as that employed in 3phase squirrel cage induction motor. The single cage and double cage induction motors formulation is presented in section 3. Induction motor, magnetoharmonic model, transient magnetic model, experimental validation. The threephase squirrel cage induction motor can, and many times does, have the same armature stator winding as the threephase synchronous motor. A highspeed squirrel cage induction machine requires totally different design compared to the traditional squirrel cage industrial motor because of mechanical limitations caused by the high speed. This work is introducing the designing of new three phase squirrel cage induction motor with an objective of getting good efficiency. In order to understand the speed control, theory and methods, it is important that the basic theory of the controlled component i.
An asynchronous motor is popularly called as induction motor. In section 4, the proposed ann and anfis models for the parameters estimation of the induction motors are introduced. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. Construction of squirrel cage induction motor explained. Parameters estimation of squirrelcage induction motors using. Squirrel cage motors have a heavy winding made up of solid bars, usually aluminum or copper, joined by rings at the ends of the rotor. Reaction of a squirrel cage rotor in a 2pole field in the rotor reference frame. What are the advantages of a squirrelcage induction motor. Introduction this manual provides information on how to safely install, couple to the driven equipment, and maintain the toshiba squirrel cage mediumvoltage induction motor.
Design of squirrel cage three 3 phase squirrel cage induction motor free download as pdf file. Section 2 summarizes the dynamic squirrelcage induction motor model. This paper presents a mathematical model of 3phase squirrelcage induction motor accounting for a very high number of space harmonics in which, due to application of a special transformation of voltages and currents, a differential equation system with. Almost 80% of the mechanical power used by industries is provided by three phase induction motors because of its simple and rugged construction, low cost, good operating characteristics, the absence of commutator and good speed regulation. Direct torque and flux control of squirrel cage induction motor. The relative motion between this field and the rotation of the rotor induces electric current in the conductive bars. Pdf squirrel cage induction motor design and the effect of. In an induction motor, the electric current in the rotor needed to produce torque is obtained via electromagnetic induction from the rotating magnetic field of the stator winding. Abstract the paper presents a novel control method for direct. In operation, the nonrotating stator winding is connected to an alternating current power source.
Nov 27, 2019 the three phase induction motor is the most widely used electrical motor. These motors are tested to strict quality control for routine and type tests at every stage of production and are ideally suitable for various industrial applications. What are the application of three phase squirrel cage rotor. Now let us discuss in detail, the most common form of induction motor, the squirrel cage induction motor. There is uniform air gap between stator and rotor but no electrical connection between. Low voltage three phase ac induction motor, squirrel cage. Induction motor with designed rotor is capable for use in overloading conditions. A squirrelcage rotor is the rotating part of the common squirrelcage induction motor. This paper presents the design of threephase induction motor im for high speed with torque speed curve suitable for vehicle propulsion applications. Difference between squirrel cage and slip ring motors. Three phase induction motors used in explosive atmospheres w60 line squirrel cage rotor horizontal date. Induction motor torquespeed characteristics figure 6. Design of squirrel cage three 3 phase squirrel cage induction. This rotating magnetic field has a speed which is known as the synchronous speed this rotating magnetic field induces the voltage in rotor bars and hence shortcircuit currents start flowing in the rotor bars.
The rotor of an induction motor can be a squirrel cage rotor or wound. Induction motors are the most widely used in domestic, commercial and various industrial applications. Compared to squirrel cage rotor the rotor construction is not simple. Design of a three phase squirrel cage induction motor for electric. Model repair specifications for low voltage induction motors these model repair specifications are intended to cover routine repair and rewind of lowvoltage randomwound threephase ac squirrel cage induction motors. But the rotor construction differs with respect to the type of motor. Choose specific magnetic and specific electric loading wbm 2 as average flux density in the airgap. The field windings in the stator of an induction motor set up a rotating magnetic field through the rotor.
The mathematical design of motor consist of nonlinear expressions, several constraints such as core saturation, thermal limits, etc. Electrical grade copper is used in very large 250 hp, 200 kw motors and in some smaller special purpose motors. This paper presents a comparative analysis in terms of results accuracy and computational effort of two numerical models used for the 2d finite element analysis of the threephase squirrelcage induction motor. Former is cheaper and broadly used as it requires less maintenance than later one. When a 3 phase supply is given to the stator winding it sets up a rotating magnetic field in space. A squirrel cage induction motor therefore draws a very high starting. The magnetization current im flowing in the motors equivalent circuit fig. Direct torque and flux control of squirrel cage induction. Deivasahayam gopalakrishnan ranganathan induction motors account for approximately 50% of the overall electricity use in industrialized countries. A motor rating of 10 horse power, 415 volts with 1440 rpm and 4pole is selected for design problem and an equivalent circuit model is developed to find out the various.
Nov 28, 2012 4 thoughts on design of squirrel cage induction motor jagdish singh june 10, 2015 at 11. Starting of squirrel cage induction motors485 an induction motor can be regarded as a transformer with a small air gap in the magnetic circuit. What is the difference between an induction motor and a. Slip ring induction motor is made up from wound rotor and squirrel cage induction motor is made up from the squirrel cage rotor.
Squirrel cage induction motor the engineering projects. However, should the motor require service, this manual includes a section that assists the. The rotor will constantly be turning to align its magnetic field with that of the stator field. Variable voltage variable frequency vf control theory an induction motor compared to a dc motor has some major advantages such as. Pdf improving squirrel cage induction motor efficiency.
In my last article, we have discussed squirrel cage induction motor which is a type of 3 phase induction motor today, i am going to tell you about a wound rotor induction motor, which is also a type of 3 phase induction motor. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. Reaction of a squirrelcage rotor in a 2pole field in the rotor reference frame. Although the design procedures for induction motors are well established, there are some areas which require special attention. Control of motorcharacteristics by squirrelcage rotordesign the reactance x2 in an induction motor equivalent circuit represents the referred form of the rotors leakage reactance. Jul 25, 2019 squirrel cage induction motor working principle. Cage rotor induction motor im is widely accepted as the most potential candidate for electric propulsion owing, to their reliability, robustness, less maintenance. Pdf squirrel cage rotor design and manufacturing for.
Oct 09, 2016 a 3 phase induction motor has two types based on the rotor construction, named as. There are two basic reasons for the use of singlephase motors rather than 3phase motors. It converts electrical energy into mechanical energy and it is used to provide motion. Aug 02, 2016 almost 90% of induction motors are squirrel cage rotor type since this type of rotor possesses the simplest and most rugged construction imaginable and is almost indestructible. This is because the squirrel cage motor has a simple and rugged construction. In slip ring induction motors the rotor is wound type. Design of a three phase squirrel cage induction motor for. Analysis and design of ac induction motors with squirrel cage rotors. Know about the most popular and almost unbreakable construction of squirrel cage induction motor.
Search wegthreephaseinductionmotorstlinesquirrelcagerotor12364818manualenglish. Design of a threephase squirrelcage induction motor based on efficiency maximization using fem software mucet2008paper no here. Kanpur, india design of a three phase squirrel cage induction motor for electric propulsion system ravi prakash,mohammad junaidakhtar, r. Threephase induction motors used in explosive atmospheres low and high. Skin effect may not be neglected in linestart motors when assessing the starting, or breakdown torque. Torquespeed characteristics of three phase squirrel cage induction motor aim to obtain the torquespeed characteristics tn r of a three phase squirrel cage induction motor using 1.
Omar almukhtar universitylibya benha university, egypt. Squirrel cage induction motor and wound rotor induction motor. Also appreciate the rugged construction of squirrel cage rotor and know the spectacular reasons for the skewed arrangements of the rotor conductors. Parameters estimation of squirrelcage induction motors.
An induction motor also known as an asynchronous motor is a commonly used ac electric motor. This paper presents design of a squirrel cage rotor for safety and reliability improvement a three phase induction machine. Pdf design and analysis of squirrel cage induction motor in short. Design optimization of three phase squirrel cage induction motor. Faculty of engineering tobruk, faculty of engineering benha2 1, 2. The threephase induction motor squirrel cage has a characteristic change in the event of a change in temperature beyond the motor operation, which leads to changes in the stator so that the resistance value affects the performance of the rotational speed of the motor, the motor rotation speed changes are. Review on efficiency improvement in squirrel cage induction motor by using dcr technology subramanian manoharan.
In traditional designs of 60 hz linefed induction machines, skin effect is represented by correction coefficients k r and k x for bar resistance and slot leakage inductance. When one considers only the bars and rings as a whole, they are much like an animals rotating exercise cage, hence the name. In traditional designs of 60 hz linefed induction machines, skin effect is represented by correction coefficients k. Dec 10, 2015 watch this video and learn basics of squirrel cage induction motor. Section 2 summarizes the dynamic squirrel cage induction motor model. Pdf design of a threephase squirrelcage induction motor. Electrical grade copper is used in very large 250 hp, 200.
The singlephase motor stator has a laminated iron core with two windings arranged perpendicularly. For motors falling outside this description, the more comprehensive model specifications below are recommended. 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. Model repair specifications for low voltage induction motors. As in the synchronous motor, applying threephase currents to the armature creates a synchronously rotating magnetic field. Oct 10, 2016 hi friends, i hope you are fine and having fun. The sinusoidally distributed flux density wave is moving at slip speed inducing in the rotor cage voltages of magnitude indicated by the blue vertical lines. The squirrel cage induction motor was designed for an extended service life under very demanding. Modeling and control of squirrel cage induction generator. Horizontal squirrel cage mediumvoltage induction motor. In this work a conventional three phase squirrel cage type induction motor with specifications 10 hp, 415v, stardelta connected and 4 poles is chosen for comparison with our motor, which is designed for good efficiency. The induction motor rotor is a completely shortcircuited conductive cage. Designing of three phase squirrel cage induction motor for. The rotating magnetizing field represented by the space vector b m or, equivalently by the magnetizing current i m moves at the synchronous speed.
Third international conference on advances in control and optimization of dynamical systems march 15, 2014. An anisotropic homogeneous representation for both squirrelcage rotor and stator windings is used. Squirrel cage induction motors menzel elektromotoren. Specifications of the induction motor to be designed. Menzel squirrel cage induction motors are manufactured for various industries and industrial applications of all kinds. Single phase induction motor the singlephase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills, compressors, pumps, and so forth. In section 4, the proposed ann and anfis models for the parameters estimation of. The reason for the name squirrel cage is because of the type of rotor used in these motors. In squirrel cage induction motors the rotor is simplest and most rugged in construction. A synchronous motor may have a squirrel cage winding embedded in its rotor, used to increase the motor starting torque and so decrease the time to accelerate to synchronous speed. Squirrel cage definition and meaning collins english. Search wegthreephaseinductionmotorstlinesquirrelcage.
It is simple and relatively inexpensive, and the absence of sliding contacts in the squirrelcage machine reduces maintenance to a minimum. The basic idea of an electric motor is to generate two magnetic fields. The threephase squirrelcage induction motor can, and many times does, have the same armature stator winding as the threephase synchronous motor. Traditional design of cage rotor induction motors ronald g. This rotating magnetic field has a speed which is known as the synchronous speed. Vfd controlled induction motor efficiency measurement. A squirrel cage is the rotor of an induction motor with a cylindrical winding with copper bars around the edge parallel to the axis. On a mathematical model of squirrelcage induction motors. Squirrel cage induction motor vs slip ring induction motor. Menzel squirrel cage motors are available in all standard motor cooling and protection types for lowvoltage from 75 kw as well as medium and high voltage up to 25,000 kw. Know about the different winding slots, lamination of the stator and its construction. Parida department of electrical engineering national institute of technology, silchar,assam, india email. The 3phase set of currents, each of equal magnitude and with a phase. Wound rotor induction motor the engineering projects.