The stator of a double cage rotor of an induction motor is same as that of a normal induction motor. A 3 phase induction motor has two types based on the rotor construction, named as. Introduction cage rotor induction motor im is widely accepted as the most potential candidate for electric propulsion owing, to their reliability, robustness, less maintenance and ability to work in hostile environments. Model repair specifications for low voltage induction motors. Three phase induction motors used in explosive atmospheres w60 line squirrel cage rotor horizontal date. Parida department of electrical engineering national institute of technology, silchar,assam, india email. Search wegthreephaseinductionmotorstlinesquirrelcagerotor12364818manualenglish. A squirrel cage is the rotor of an induction motor with a cylindrical winding with copper bars around the edge parallel to the axis. The effect of stator slots and teeth is included by a second anisotropic homogeneous medium. What are the application of three phase squirrel cage rotor. Pdf improving squirrel cage induction motor efficiency.
Threephase induction motors used in explosive atmospheres low and high. The rotor is constructed using a number of single bars shortcircuited by end rings and arranged in a. Squirrel cage motors are the most commonly used induction motors, but the main drawback in them is their poor starting torque due to low rotor resistancethese drawbacks are removed by a double squirrel cage motor, which has high starting torque without sacrificing efficiency. The larger the motor power, the more severe this phenomenon. These bars are shorted at each end with shorting rings. Ip56 w22xd ie2 high efficiency explosao portugal rev. The squirrel cage rotor consists of a laminated iron core which is slotted lengthwise around its periphery. Normally, we use the motors in industrial drives because they are rugged, reliable and economical. Squirrel cage induction motors menzel elektromotoren. 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. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. Know about the most popular and almost unbreakable construction of squirrel cage induction motor. Menzel squirrel cage induction motors are manufactured for various industries and industrial applications of all kinds.
Recall that leakage reactance is the reactance due to the rotor flux lines that do not also couple with the stator windings. 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. Modeling and control of squirrel cage induction generator. Torquespeed characteristics of three phase squirrel cage. Squirrel cage induction motors are very widely used in both fixedspeed and variablefrequency drive applications. For motors falling outside this description, the more comprehensive model specifications below are recommended. This arrangement is used for obtaining high starting torque at a low value of starting current.
Reaction of a squirrel cage rotor in a 2pole field in the rotor reference frame. Load tests on a threephase induction motor and measurement of the inrush current objectives. An induction motors rotor can be either wound type or squirrelcage type. In operation, the nonrotating stator winding is connected to an alternating current power source.
The field windings in the stator of an induction motor set up a rotating magnetic field through the rotor. Differentiate between the various types of generating electric power stations. The conversion process is electromagnetic induction. 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. This experiment is performed on a threephase squirrel cage induction motor when the rotor is not allowed to rotate. Background the simplest and most widelyused rotor for induction motors is the socalled squirrel cage rotor, from which the squirrel cage induction motor gets its name. Traditional design of cage rotor induction motors ronald g. 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. But increasing the rotor resistance for improving starting torque is not advisory as it will reduce the efficiency of the motor due to more copper loss.
Starting torque is directly proportional to the rotor resistance. Firstly, i am going to tell you about the structure of squirrel cage induction motor. Control of motorcharacteristics by squirrelcage rotordesign. List and describe the more commonly used equipment in an electric substation.
Squirrel cage construction, the rotor winding consists of a number of rotor bars, shortcut by rings from both side, see figure below. Control of motorcharacteristics by squirrelcage rotordesign the reactance x2 in an induction motor equivalent circuit represents the referred form of the rotors leakage reactance. It converts electrical energy into mechanical energy and it is used to provide motion. To determine for an induction motor on block rotor test, relationship. When the rotor is blocked, only a small amount of voltage.
However, should the motor require service, this manual includes a section that assists the. Three phase squirrel cage induction motor with inverter section model 0100hz. Double squirrel cage induction motor your electrical guide. Construction of squirrel cage induction motor explained. Data sheet three phase induction motor squirrel cage. The effect of variation of stator voltage on input power, and stator current are explained as follows. The main difference between slip ring and squirrel cage induction motor is the rotor construction. Squirrel cage definition and meaning collins english. An induction motor or asynchronous motor is an ac electric motor in which the electric current.
What are the specific applications of squirrel cage and. It depends on the frequency and the amplitude of the magnetic field. 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. Mainly we discuss a threephase squirrel cage induction motor. May 20, 2015 the threephase induction motor the squirrel cage induction motor the woundrotor induction motor 3 4. Energy efficiency improvement of a squirrelcage induction motor. 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 test is similar to shortcircuit on a transformer.
Abstract this paper describes a method to analyze harmonic magnetic fields of squirrel cage induction motors considering rotor skew and. 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. Third international conference on advances in control and optimization of dynamical systems march 15, 2014. It consists of a cylinder of steel laminations, with aluminum or copper. The squirrel cage winding of a synchronous machine will generally be smaller than for an induction machine of similar rating. Jul 25, 2019 squirrel cage induction motor working principle. Design of a three phase squirrel cage induction motor for electric propulsion system. The squirrel cage induction motor was designed for an extended service life under very demanding conditions.
Magnetic field analysis of a squirrel cage induction motor. To obtain the load performance characteristics of a threephase squirrel cage induction motor. Two digital multimeters and fluke power quality meter with banana cables from the. A 3 phase ac induction motor photoed by hordu motor. An induction motor can therefore be made without electrical connections to the rotor. Designing of three phase squirrel cage induction motor for.
Double cage rotor of an induction motor a double cage induction motor is that type of motor in which a double cage or two rotor windings or cages are used. Electric motor construction of induction motors britannica. Know about the different winding slots, lamination of the stator and its construction. The upper slot conductors from the outer cage and the lower slot conductors form the inner cage. Squirrel cage induction motor and wound rotor induction motor. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. We saw the construction of the squirrel cage induction motor. Lecture 6 three phase induction motors cairo university. Design of a three phase squirrel cage induction motor for.
A double squirrel cage rotor is shown in the figure. 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 squirrel cage induction motor is the most commonly used motor in industry. In traditional designs of 60 hz linefed induction machines, skin effect is represented by correction coefficients k. Advantages of three phase squirrel cage induction motor. The rotor is constructed using a number of single bars shortcircuited by end rings and arranged in a hamsterwheel or squirrel cage configuration. Parameters identification of the threephase squirrelcage induction. The reason for the name squirrel cage is because of the type of rotor used in these motors. Modeling and control of squirrel cage induction generator with full power converter applied to windmills dom nguez garc a, jos e luis november 30, 2009. Horizontal squirrel cage mediumvoltage induction motor. To measure the inrush current when the motor starts. A squirrelcage rotor is the rotating part of the common squirrelcage induction motor.
The majority of commercial and industrial applications usually involve the use of a threephase squirrelcage induction motor. Summary of changes performed checked date performed by joseconde checked by marcioaf date 03082016 152016 page 11 revision 2. A 1phase induction motor is similar to a 3phase squirrel cage induction motor in physical appearance. How are squirrel cage induction motors constructed. In a squirrel cage induction motor, the rotor has conductive bars embedded in slots in the laminations, running the length of the rotor.
There is no electrical connection between these bars. Former is cheaper and broadly used as it requires less maintenance than later one. Section 2 summarizes the dynamic squirrelcage induction motor model. What is the difference between a squirrel cage motor and a. Learn the working principle and applications of a squirrel cage induction. The three phase squirrelcage induction machine is the most used motor in industry applications. Analysis and design of ac induction motors with squirrel cage rotors. An induction motor also known as an asynchronous motor is a commonly used ac electric motor. This rotor is made up from parallel aluminum or copper bars. Pdf design of a threephase squirrelcage 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 relative motion between this field and the rotation of the rotor induces electric current in the conductive bars. Scope regulation eu 42014 covers single speed, threephase, 50 hz and 60 hz induction motors with.
Data sheet three phase induction motor squirrel cage customer. In section 4, the proposed ann and anfis models for the parameters estimation of. This rotating magnetic field has a speed which is known as the synchronous speed. 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. The rotor is same as that employed in 3phase squirrel cage induction motor. 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. The iec 60034301 is part of an effort to unify motor testing standards, efficiency requirements and product. Variable voltage variable frequency vf control theory an induction motor compared to a dc motor has some major advantages such as. It is low cost and requires low maintenance in comparison with other motor types. 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. The magnetization current im flowing in the motors equivalent circuit fig. 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 torque of the induction motor depends on the rotor resistance. Squirrel cage motors are the most commonly used induction motors, but the main drawback in them is their poor starting torque due to low rotor resistance.
The rotor of an induction motor can be a squirrel cage rotor or wound type rotor. Dec 10, 2015 watch this video and learn basics of squirrel cage 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. 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. 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. Harley and yao duan georgia institute of technology november, 2009. Kanpur, india design of a three phase squirrel cage induction motor for electric propulsion system ravi prakash,mohammad junaidakhtar, r. Squirrel cage induction motor the engineering projects. Oct 09, 2016 a 3 phase induction motor has two types based on the rotor construction, named as. 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. The rotor will constantly be turning to align its magnetic field with that of the stator field. Wound rotor induction motor the engineering projects. When a 3 phase supply is given to the stator winding it sets up a rotating magnetic field in space.
In most induction motors, the rotor winding is of the squirrelcage type where solid conductors in the slots are shorted together at each end of the rotor iron by. Construction of double squirrel cage induction motor a double squirrel cage induction motor consists of a rotor which has two independent cages one above the other in the same slot. The singlecage and doublecage induction motors formulation is presented in section 3. The basic idea of an electric motor is to generate two magnetic fields. Now let us discuss in detail, the most common form of induction motor, the squirrel cage induction motor.
There are two basic reasons for the use of singlephase motors rather than 3phase motors. Oct 19, 20 three phase squirrel cage induction motor with inverter section model 0100hz. It is very commonly used in industries because it is very cheap, robust, efficient, and reliable. An anisotropic homogeneous representation for both squirrelcage rotor and stator windings is used. The 3phase set of currents, each of equal magnitude and with a phase. Reaction of a squirrelcage rotor in a 2pole field in the rotor reference frame. The squirrel cage induction motor was designed for an extended service life under very demanding. Watch this video and learn basics of squirrel cage induction motor. Parameters estimation of squirrelcage induction motors. The majority of commercial and industrial applications usually involve the use of a threephase squirrel cage induction motor. Working principle of 3 phase squirrel cage induction motor. The threephase induction motor the squirrelcage induction motor the woundrotor induction motor 3 4. Oct 10, 2016 hi friends, i hope you are fine and having fun.
Induction motor torquespeed characteristics figure 6. What are the advantages of a squirrelcage induction motor. Generatori i motorii have developed a series of totally enclosed ribcooled lowvoltage squirrelcage induction motors frame size 280450 series 6azj. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. A simple explanation of squirrel cage induction motors. The principle of working of squirrel cage and slip ring induction motor is based on faradays law of electromagnetic induction. The rotor of a squirrel cage induction motor is shor. The induction motor is mod eled as six concentric cylindrical layers. Determination of the losses in induction machines due to harmonics pdf.
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