This document is highly rated by electrical engineering ee students and has been viewed 2495 times. Difference between squirrel cage and slip ring induction motor. 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. A highspeed squirrel cage induction machine requires totally different design compared to the traditional squirrel cage industrial motor because of mechanical limitations caused by. Modelling and analysis of squirrel cage induction motor with. Designing of three phase squirrel cage induction motor for. Know about the different winding slots, lamination of the stator and its construction.
Basic construction of 3phase ac induction motors you should. The construction of stator for any induction motor is almost the same. The squirrel cage induction motor was designed for an extended service life under very demanding conditions. This simplest form of ac induction motor or asynchronous motor is the basic, universal workhorse of industry. Third international conference on advances in control and optimization of dynamical systems march 15, 2014. Design and fabrication of high efficiency squirrel cage induction motor using. Construction of induction motor electrical edition. Squirrel cage induction motor a squirrelcage induction motor is one in which the secondary circuit consists of a squirrelcage winding suitably disposed in slots in the secondary core.
Pdf principles of electrical machines book by vk mehta. 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. Test motor was tested on bench to experimentally verify the results. The stator is a stationary part and it has laminated construction, which is made up of stampings. The linear induction motor has been proposed as a drive for highspeed passenger trains.
Know about the most popular and almost unbreakable construction of squirrel cage induction motor. However, it suffers from the disadvantage of a low starting torque. Design of a three phase squirrel cage induction motor for. In first comparison, motor was supplied from laboratory source. Cheap copare to slipring im maintainance is easy cost is less compare to slipring im can use at explosive area starting torque is low compare to slip. Advantages and disadvantages of squirrel cage induction motor. A 3 phase induction motor has two main parts i stator and ii rotor. Jul 25, 2019 a 3 phase squirrel cage induction motor is a type of three phase induction motor which functions based on the principle of electromagnetism. Design, construction, and manufacture of squirrel cage rotors. Standard handbook of petroleum and natural gas engineering third edition, 2016. I g crow beng, phd, ceng, fimeche, fimare, memasme, r robinson bsc, ceng, fiee, in plant engineers reference book second edition, 2002.
Know how the speed control is easily achieved by changing the number of stator poles. Analysis and design of ac induction motors with squirrel cage rotors. Phasor diagram of induction motor on noload and loaded conditions, visualization of a threephase induction. The internal design and construction of both are not discussed you can simply read them from your theory books. It provides knowledge for industrial engineers, who use motor current signature analysis mcsa to determine if there are any cage winding breaks in their squirrel cage induction motors scims. This rotor is a cylinder of steel laminations, with highly.
An induction motor s rotor can be either wound type or squirrel cage. Parida department of electrical engineering national institute of technology, silchar,assam, india email. The slip ring motor has very little application in industries. Squirrel cage rotor consists of a set of copper or aluminium bars installed into the slots, which are connected to an endring at each end of the rotor.
Current signature analysis mcsa to determine if there are any cage winding breaks in their squirrel cage induction motors scims. It provides knowledge for industrial engineers, who use motor c. Menzel squirrel cage motors are available in all standard motor cooling and protection types for lowvoltage from 75 kw as. Dont worry, difference between squirrel cage and slip ring type induction motor is tabulated after the figure. This final thesis will mostly be dedicated to induction motors but also to synchronous permanent magnet and reluctance motors. The rotor consists of a cylindrical laminated core with parallel slots for carrying the rotor conductors which, it should be noted clearly, are not wires but consist of. Squirrel cage induction motors are more sensitive to the supply voltage fluctuations.
Depending upon the type of rotor construction used the three phase induction motor are classified as. The stator of an induction motor is laminated iron core with slots similar to a stator of a synchronous machine. Horizontal squirrel cage mediumvoltage induction motor. Tesla polyphase induction motors ac motors electronics. Closedform analysis of squirrelcage induction motors with. Induction motor teco pdf book manual free download. Motors employing this type of rotor are known as squirrel cage induction motors. Starting of squirrel cage induction motors485 an induction motor can be regarded as a transformer with a small air gap in the magnetic circuit. 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. Types of ac induction motor rotors there are twotypes of rotor windings.
Almost 90 percent of induction motors arc squirrel cage type, because this type of rotor has the simplest and most rugged construction imaginable and is almost indestructible. Some of the advantages, disadvantages and applications of squirrel cage induction motor compared with slipring induction motor are discussed below. Three phase induction motor construction electrical academia. Oct 19, 20 three phase squirrel cage induction motor with inverter section model 0100hz. Threephase ac induction motors are widely used in industrial and commercial applications.
Construction of induction motor posted by electrical. Control of motorcharacteristics by squirrelcage rotordesign. Construction of squirrel cage induction motor explained. Ppt threephase induction motor electrical engineering. Most of single phase induction motors use squirrel cage rotor as it has a remarkably simple and robust construction enabling it to operate in the most adverse circumstances. A simple explanation of how a 3 phase induction motor works. The induction motor rotor is a completely shortcircuited conductive cage.
We saw the construction of the squirrel cage induction motor. The majority of commercial and industrial applications usually involve the use of a threephase squirrel cage induction motor. These motors can operate at any working conditions. Slip ring induction motor is made up from wound rotor and squirrel cage induction motor is made up from the squirrel cage rotor. Those induction motors which employ squirrel cage rotor are called squirrel cage induction motors. Induction motors are used in applications requiring fast and precise control of. Squirrel cage induction motor an overview sciencedirect. 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. Squirrel cage induction motors menzel elektromotoren. Introduction this manual provides information on how to safely install, couple to the driven equipment, and maintain the toshiba squirrel cage mediumvoltage induction motor. The squirrel cage induction motor is by far the most common type of induction motor. An induction motor can therefore be made without electrical connections to the rotor. The rotor will constantly be turning to align its magnetic field with that of the stator field.
A wound rotor or slip ring motor has a 3phase winding, similar to the stator. Squirrel cage induction motor an overview sciencedirect topics. The rotor is constructed using a number of single bars shortcircuited by end rings and arranged in a hamsterwheel or squirrel cage configuration. The figure itself depicts many difference between the two types of motors. The wound stator and the squirrel cage rotor of an induction motor may be cut at the circumference and unrolled into a linear induction motor. Nov 27, 2019 the three phase induction motor is the most widely used electrical motor. The construction of a stator for both of the kinds of three phase induction motors is identifcal, and is discussed briefly below. With scalar control, the induction motor presently rivals permanent magnet motors in many industrial applications such as pumps, compressors, and conveyor belts. But the rotor construction differs with respect to the type which is specified above. This paper deals with analysis of high speed squirrel cage induction motor. Squirrel cage induction motor and wound rotor induction motor. The rotor consists of a cylindrical lamina ted core with parallel slots for carrying the rotor conductors which, it should be.
A 3 phase induction motor has two types based on the rotor construction, named as. Squirrel cage induction motor is used in lathes, drilling machine, fan, blower printing machines etc slip ring or wound rotor. The below diagram shows squirrel cage induction rotor having aluminum bars short circuit by aluminum end rings. A 3 phase squirrel cage induction motor is a type of three phase induction motor which functions based on the principle of electromagnetism. Threephase induction motor construction rotating magnetic field due to 3phase currentalternate analysis for rotating magnetic field.
Slip ring induction motor or wound induction motor or phase wound induction motor. Pdf three phase squirrel cage induction motor, conctruction. A squirrel cage induction motor therefore draws a very high starting. Motor, 3 phase induction motor construction, induction motor construction, working ppt, induction motor construction video, induction motor construction and working pdf. Read online induction motor teco book pdf free download link book now. A 3 phase induction motor can be used for different applications with various speed and load requirements. Diagnostics of rotor and stator problems in industrial induction motors by fang duan b. Stator of this motor is the same as the one used in squirrel cage induction motors. Kanpur, india design of a three phase squirrel cage induction motor for electric propulsion system ravi prakash,mohammad junaidakhtar, r. References 16 stator winding is placed in the stator of induction motor and the three phase 1.
Squirrel cage rotor almost 90 per cent of induction motors are squirrel cage type, because this type of rotor has the simplest and most rugged construction imaginable and is almost indestructible. 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. But the rotor construction differs with respect to the type of motor. Also appreciate the rugged construction of squirrel cage rotor and know the spectacular reasons for the skewed arrangements of the rotor conductors. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. The basic idea of an electric motor is to generate two magnetic fields. A squirrelcage induction motor is one in which the secondary circuit consists of a. Almost 90% of induction motors have squirrel cage rotors. The 3phase set of currents, each of equal magnitude and with a phase. 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. Basics of induction motors basics of electrical engineering. The ruggedness and simplicity of the squirrel cage induction motor usually makes it the first choice for a driver. A squirrel cage rotor is the rotating part of the common squirrel cage induction motor. The principle of working of squirrel cage and slip ring induction motor is based on faradays law of electromagnetic induction.
It is called a squirrel cage motor because the rotor inside of it known as a squirrel cage rotor looks like a squirrel cage. Squirrel cage wound rotor with slip rings the rotating magnetic field the basic idea of an electric motor is to generate two magnetic fields. The principal advantages of the squirrel cage induction motor are its simplicity of design and robust construction. A squirrelcage rotor is the rotating part of the common squirrel cage induction motor. These are of two types, squirrel cage and slip ring motors. Control of motorcharacteristics by squirrelcage rotordesign the reactance x2 in an induction motor equivalent circuit represents the referred form of the rotors leakage reactance. These stampings consists of slots on its periphery to carry the.
The threephase squirrel cage induction motor can, and many times does, have the same armature stator winding as the threephase synchronous motor. Normally, we use the motors in industrial drives because they are rugged, reliable and economical. These motors have the advantage of adapting any number of pole pairs. These motors are having the difference in rotor construction.
The main difference between slip ring and squirrel cage induction motor is the rotor construction. The induction motor is mod eled as six concentric cylindrical layers representing the different construction components of the motor. Most of the application of industrial as well as domestic are this type of induction motor. When the supply voltage is reduced, induction motor draws more current. A squirrel cage motor has a very good speed regulation and it is used in places where the load is varying.
This rotor consists of uninsulated copper or aluminium bars, placed in the slots. Telecommunication engineering, southwest jiaotong university, china, 2005 thesis submitted for the degree of masters of engineering science in school of electrical and electronic engineering the university of adelaide, australia august 2010. Basic construction and operating principle like most motors, an ac induction motor has a fixed. Pdf squirrel cage rotor design and manufacturing for. The laminations are aligned and heatshrunk onto the shaft, and then the molten aluminum is forced into the slots to form the squirrel cage winding.
Know about the construction of double squirrel cage motor with a graphical comparison with single cage. Induction motor construction squirrel cage rotor duration. Starting torque is directly proportional to the rotor resistance. How are squirrel cage induction motors constructed. 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. However, should the motor require service, this manual includes a section that assists the. As in other induction motors, the basic parts are stator and rotor.
Double squirrel cage motor we have already discussed that the rotor which is of squirrel cage type has two end rings, which are permanently shorted with the rotor conductors. A single phase induction motor is very similar to a 3phase squirrel cage induction motor. This explains single phase induction motors working principle and construction. The ac induction motor comprises two electromagnetic parts. Recall that leakage reactance is the reactance due to the rotor flux lines that do not also couple with the stator windings. The shaded pole induction motor has no commutator, brushes, collector rings, contactors, capacitors or moving switch parts, so it is relatively cheaper, simpler and extremely rugged in construction and reliable.
Working principle of 3 phase squirrel cage induction motor. This chapter presents the essential features of the design, construction, and manufacture of squirrel cage induction rotors. Squirrel cage induction motortable of contents1 squirrel cage induction motor2 slip ring or wound induction motor3 advantages of squirrel cage induction motor4 advantages of slip ring induction motor5 disadvantages of squirrel cage induction. Introduction to induction motor instrumentation and control. Most of three phase induction motor use squirrel cage rotor as it has a remarkably simple and robust construction enabling it to operate in the most adverse circumstances.
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. It is very commonly used in industries because it is very cheap, robust, efficient, and reliable. The direction of linear travel is controlled by the sequence of the drive to the stator phases. Former is cheaper and broadly used as it requires less maintenance than later one. Coils are placed in the slots to form a three or single phase winding. Pdf design and fabrication of high efficiency squirrel cage.
The squirrel cage induction motor was designed for an extended service life under very demanding. Introduction to induction motor instrumentation and. In operation, the nonrotating stator winding is connected to an alternating current power source. Diagnostics of rotor and stator problems in industrial. These motors are selfstarting and use no capacitor, start winding, centrifugal switch or other starting device. Types of single phase induction motors electronics hub. There are two types of induction motors, one with wound type rotor, also called slipring motor and another one with squirrel cage rotor. The rotor is built of a stack of steel laminations, such as the one shown in figure 3. Firstly, i am going to tell you about the structure of squirrel cage induction motor. An induction motor always operates at a speed lower than the synchronous speed because the rotating magnetic field that occurs in the stator will generate flux in the rotor that will cause the rotor to rotate, but due to the delay of the flow current in the rotor with current flow in the stator, the rotor will never reach its rotating magnetic field speed, that is, the synchronous speed. Induction motor basics, single phase and three phase. 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.
Reaction of a squirrel cage rotor in a 2pole field in the rotor reference frame. The construction of this type of rotor along with windings resembles a squirrel cage. Learn a brief history of the electrical power systems construction. By far the most commonly used ac motor is the induction motor. Construction of three phase induction motor electrical4u. Bsc, ceng, fiee, in plant engineers reference book second edition, 2002. All questions related to transistor will be clear here by blogs. Wound rotor induction motor the engineering projects. Shaded pole induction motors working and construction. We also discuss the construction of a three phase motor. Pdf squirrel cage rotor design and manufacturing for high.
Design, construction, and manufacture of squirrel cage. Pdf novel multiflux level, threephase, squirrelcage induction. The construction of these motors is more or less similar to a threephase squirrel cage induction motor. The rotor of a squirrel cage induction motor is shor. When a 3 phase supply is given to the stator winding it sets up a rotating magnetic field in space. What are the specific applications of squirrel cage and. This site is like a library, you could find million book here by using search box in the header. What are the advantages of a squirrelcage induction motor. 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. These motors fill most generalpurpose, constantspeed drive requirements. The absence of a centrifugal switch eliminates the possibility of motor failure due to faulty centrifugal switch mechanisms. Stator is also provided with a starting winding which is used only for starting purpose.
Pdf principles of electrical machines book by vk mehta and rohit mehta pdf download. A 1phase induction motor is similar to a 3phase squirrel cage induction motor in. Please have a look at the below figures of squirrel cage induction and wound rotor slip ring induction motor. Oct 09, 2016 a 3 phase induction motor has two types based on the rotor construction, named as. Concept of rotating magnetic field, operating principle, construction, classification and types singlephase, threephase, squirrel cage, slipring, double cage types. Apr 18, 2020 ppt threephase induction motor electrical engineering ee notes edurev is made by best teachers of electrical engineering ee. Squirrel cage induction motor the engineering projects.
The singlephase induction motor is not selfstarting. Although single phase induction motor is more simple in construction and is cheaper than a 3phase induction motor of the same frame size, it is less efficient and it operates at. Menzel squirrel cage induction motors are manufactured for various industries and industrial applications of all kinds. All books are in clear copy here, and all files are secure so dont worry about it. Dec 19, 2015 single phase induction motors consist of two main parts. Three phase squire cage induction motor, fully enclosed. Stator winding spreading the coil in this manner creates a sinusoidal flux distribution per pole, which improves performance and makes the motor less noisy sound and electrically. The construction of stator of the induction motor is almost the same as other motors. The rotor is separated from the stator by a small airgap which ranges from 0. The winding arrangement of a symmetrical induction machine is shown in figure 2. Squirrel cage induction motors are cheaper in cost compared to slip ring induction motors. Construction of a single phase induction motor is similar to the construction of three phase induction motor having squirrel cage rotor, except that the stator is wound for single phase supply.
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