Difference between squirrel cage and wound rotor induction motor pdf

Wound rotor induction motors ac motors electronics. Mar 07, 2016 a wound rotor motor slip ring motor is a type of induction motor where the rotor windings are connected through slip rings to external resistances. One of the major difference between the slip ring and the squirrel cage motor is that the slip ring motor has an external resistance circuit for controlling the speed of the motor. An induction motor can therefore be made without electrical connections to the rotor. The rotor of the latter, however, as the name implies, has windings. The significant difference between the rotor and the stator is that the rotor is the rotating part of the motor whereas the stator is the stationary part of the motor. While slip ring induction motors also known as woundrotor motor arent as. Oct 09, 2016 a 3 phase induction motor has two types based on the rotor construction, named as. Whereas in squirrel cage motor, it is not possible to add any external circuit because the bar of the motor is permanently slotted at the end of the ring. Firstly, i am going to tell you about the structure of squirrel cage induction motor.

Difference between squirrel cage and slip ring induction motor. In a squirrel cage induction motor, the rotor has conductive bars embedded in slots in the laminations, running the length of the rotor. The figure itself depicts many difference between the two types of motors. May 31, 2012 the two main parts of the induction motor are the stator, and the rotor. Whats the difference between ac induction, permanent. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. Stator winding is similar to that of a synchronous motor. The stator of a wound rotor motor is constructed and operates in the same way as the squirrel cage motor. A wound rotor motor is a type of induction motor where the rotor windings are connected through slip rings to external resistances. The woundrotor motor is a variation of the squirrelcage induction motor. D of the main panel for a hospital, showing meter position.

Pdf comparison of 5 different squirrel cage rotor designs. Low starting current compared to squirrel cage induction motor. Difference between squirrel cage and phase wound induction. Its synchronous speed with a 50 hz supply is therefore 60 fp, or 1500 rpm. Mar 09, 2018 in this article, we will learn about squirrel cage and slip ring induction motors. These bars are shorted at each end with shorting rings. Difference between squirrel cage and phase wound induction motor.

Construction of ac cage and wound rotor motors blogger. The winding of the rotor is excited by the dc supply. The motor which employing the wound rotor is known as a slip ring induction. A wound rotor induction motor has a stator like a squirrel cage induction motor, but. The other differences between the stator and rotor are shown below in the comparison chart. Typical applications include cranes, large compressors, elevators, and pumps. Slip ring induction motor srim vs squirrel cage induction motor scim. The rotor core and the rotor winding are the part of the rotor. One of the major difference between the slip ring and the squirrel cage motor is. One type is called squirrel cage motor and the other is called wound rotor induction motor wrim. The point of this woundrotor configuration is to provide a means of reducing the.

Squirrel cage wound rotor with slip rings the rotating magnetic field the basic idea of an electric motor is to generate two magnetic fields. Difference between squirrel cage and wound rotor induction. In operation, the nonrotating stator winding is connected to an alternating current power source. Compared to a squirrelcage rotor, the rotor of the slip ring motor has more winding turns. Each pole is wired in series with a variable power resistor. The rotor conductors, though, are not short circuited but are terminated to a set of slip rings as in the diagram above, these slip rings do not have power applied. A woundrotor motor, also known as slip ringrotor motor, is a type of induction motor where the. The rotor of the squirrel cage motor has no winding, and there is no need for the rotor to be electrically connected to any electricity. In this article, we will explain the difference between squirrel cage and phase wound induction motor with different factors. The rotor of a squirrel cage induction motor is constructed of a laminated core with the conductor placed parallel parallel to the surface of the core. Instead of the rotor being the squirrel cage of a standard induction motor bars of conductor material joined at the ends by rings, the entire assembly embedded. Three phase squire cage induction motor, fully enclosed.

Slip ring induction motor fundamentals pnpntransistor. Compared to squirrel cage rotor the rotor construction is not simple. This rotor is a cylinder of steel laminations, with highly conductive metal typically aluminum or copper embedded into its surface. In this article we are going to discuss differences between squirrel cage and slip ring induction motor.

This simplest form of ac induction motor or asynchronous motor is the basic, universal workhorse of industry. A squirrel cage rotor has very low resistance bars cast into the rotor steel which acts as the secondary windings. This rotor is made up from parallel aluminum or copper bars. Jul 25, 2019 difference between squirrel cage and slip ring induction motor. Costs of maintenance and initial investment are certainly much lower for an iscm, that is why it is the first selection as far as it could be tailored properly to the load. Squirrel cage induction motor and wound rotor induction motor. The squirrel cage and the phase wound are the types of the rotor. An electric motor with a squirrel cage rotor is termed a squirrel cage motor. This is because the squirrel cage motor has a simple and rugged construction. The rotor consists of copper bars not insulated, shortcircuited at their end by two conductive rings and constitute a squirrel cage. While slip ring induction motors also known as woundrotor motor arent as popular as squirrel cage induction motors, they do have a few advantages. This cage is swept by the rotating magnetic field 4.

Adjusting the resistance allows control of the speedtorque characteristic of the motor. Also appreciate the rugged construction of squirrel cage rotor and know the spectacular reasons for the skewed arrangements of the rotor conductors. It is usually designed for fixedspeed operation, larger ratings having such features as deep rotor bars to limit direct on line dol starting currents. The squirrel cage rotor is the most popular rotor in induction motor. Srim rotor consists of a threephase winding similar to the stator winding, but in scim the rotor consists of bars which are shortened at the ends with help of end rings.

Know about the most popular and almost unbreakable construction of squirrel cage induction motor. It is simple and relatively inexpensive, and the absence of sliding contacts in the squirrel cage machine reduces maintenance to a minimum. Threephase squirrel cage induction motors are widely used as industrial drives because they are selfstarting, reliable and economical. Squirrel cage induction motor squirrel cage induction motors are usually used in various industrial applications. Speed is the resistance variable over 50% to 100% full speed. Srim rotor construction is very complicated but in scim the rotor construction is. 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. Synchronous and asynchronous ac inductionasynchronous motor a major difference between the wound rotor motor and the squirrel cage rotor is that the conductors of the wound rotor consist of wound coils instead. Below is a comparison table of squirrel cage vs wound rotor type motors. The rotor of the slip ring motor has a cylindrical core with parallel slots, and each slot consists each bar. In slip ring induction motors the rotor is wound type.

These are helpful in adding external resistors and contactors. The rotating part of the motor is known as the rotor. In squirrel cage rotor, the rotor bars are permanently shortcircuited with end rings. It is also possible to find induction motors containing rotors made up of windings rather than a squirrel cage. The rotor will constantly be turning to align its magnetic field with that of the stator field. Difference between synchronous motor and induction motor.

Jun 24, 2017 difference between squirrel cage and slip ring induction motor on our electrical learning portal we have posted articles based on comparisons and differences. Nov 07, 20 wound rotors for dc machine or alternators squirrel cage rotors for ac induction motor. A 3 phase squirrel cage induction motor is a type of three phase induction motor which functions based on the principle of electromagnetism. A squirrel cage rotor or a wound rotor can be used.

Apr 18, 2019 difference between cage rotor and slip ring rotor a wound rotor is a type of induction motor where the rotor windings are connected through slip rings to external resistance. Rotor as the name suggests it is a rotating part of an electrical machine, in which current is induced by transformer action from rotating magnetic field. But in the case of the phase wound induction motor, the rotor winding has the arrangement to connect the external resistance which used to increase the starting torque and speed regulation. Dont worry, difference between squirrel cage and slip ring type induction motor is tabulated after the figure. Know about the different winding slots, lamination of the stator and its construction. The most popular squirrel cage induction motor is of a 4pole design. In squirrel cage induction motors the rotor is simplest and most rugged in construction. Whats the difference between ac induction, permanent magnet. Squirrel cage rotor and slip ring rotor squirrel cage vs wound. Wound rotor induction motors ac motors electronics textbook. The major difference is the external resistance circuit for controlling the speed of the motor. May 18, 2018 please have a look at the below figures of squirrel cage induction and wound rotor slip ring induction motor. Slip ring induction motor srim vs squirrel cage induction.

A wound rotor motor is a type of induction motor where the rotor windings are connected. Squirrel cage rotor wound type rotor or slip ring type rotor squirrel cage rotor in this type. Construction of squirrel cage induction motor explained. What is the difference between a squirrel cage motor and a wound. Electrical interview questions which motor is best. 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. Laminations from typical squirrelcage induction motor rotors, showing the. A squirrelcage rotor is the rotating part of the common squirrelcage induction motor. The wound rotor motor is a variant of the squirrel cage motor arrangement.

The reactance x2 in an induction motor equivalent circuit represents the referred. A wound rotor induction motor has a stator like a squirrel cage induction motor, but a rotor with insulated windings brought out via slip rings and brushes however, no power is applied to the slip rings. Difference between cage rotor and slip ring rotor basic. A special type of ac induction motor, known as wound rotor motors, will be the main focus of this article. A novel three phase induction motor analysis of its. Compared to the squirrel cage induction motor, the wound rotor motor has the following advantages. We saw the construction of the squirrel cage induction motor. Pdf improving squirrel cage induction motor efficiency. Squirrel cage induction motor the engineering projects. Stator in the induction motor is a series of concentric magnetic poles usually electromagnets, and the rotor is a series of closed windings, or aluminium rods arranged in a way similar to a squirrel cage, hence the name squirrel cage rotor. Higher maintenance of brushes and slip rings compared to squirrel cage motor. The 3phase set of currents, each of equal magnitude and with a phase difference of 120o, flow in the stator windings and generate a rotating.

Jan 11, 2019 it is also possible to find induction motors containing rotors made up of windings rather than a squirrel cage. In the case of squirrel cage induction motor, rotor bars. The stationary part of the motor is called stator and rotary part of the motor is called rotor. An induction motors rotor can be either wound type or squirrelcage type. Slip ring induction motor is also known as wound rotor induction motor. The core of the squirrel cage rotor is made of the cylindrical iron core. But the rotor construction differs with respect to the type which is specified above. While only used in special scenarios, these motors have a distinct advantage over other popular choices squirrel cage, synchronous motors, etc. Control of motor characteristics by squirrelcage rotor design. The works of the stator is common in all motor to develop a magnetic field. Feb 16, 20 it consists of a cylinder of steel with aluminum or copper conductors embedded in its surface. In wound rotor, windings are also permanently shortcircuited, hence no slip rings are.

The point of this wound rotor configuration is to provide a means of reducing the. There are a lot of basic differences between a slip ring rotor also known as wound rotor and a squirrel cage induction motor. Lecture 6 three phase induction motors cairo university. A wound rotor induction motor is used when a strong starting torque and a range of speed control are required.

The motor whose rotor is wound type such type of motor is called slip ring induction motor, whereas the squirrel cage motor, has a squirrel cage type rotor. Former is cheaper and broadly used as it requires less maintenance than later one. Wound rotor motors can be started with low inrush current, by inserting high resistance into the rotor circuit. The point of the construction is to provide a means of reducing the rotor current as the motor first begins to spin. Please have a look at the below figures of squirrel cage induction and wound rotor slip ring induction motor. Squirrel cage type rotor almost 90% of induction motors are squirrel cage motors. Whats the difference between asynchronous and synchronous. Differences between synchronous motor and induction motor. That makes a wrim wound rotor induction motor performance very superior if compared to an iscm induction short circuited rotor motor squirrel cage. What is the difference between a squirrel cage motor and a. The ac inductor rotor assembly resembles a cage consisting of aluminum or copper conducting bars connected by shortcircuiting end rings hence the nickname squirrel cage for induction motors.

Difference between slip ring and squirrel cage induction motor. For a fullload operating slip of 3 per cent, the speed will then be 1 s60 fp, or 1455 rpm. Almost 90% of induction motors are provided with squirrel cage because of its very simple robust and almost instructible construction. A slip ring wound rotor motor has insulated wire rotor windings which feed out through slip rings to a bank of large variable resistors where the resistance of the rotor circuit can be varied. An induction motor s rotor can be either wound type or squirrel cage type.

Squirrel cage induction motor vs slip ring induction motor. It is simple and relatively inexpensive, and the absence of sliding contacts in the squirrelcage machine reduces maintenance to a minimum. They are particularly suited for applications where the motor must maintain a constant speed, be selfstarting, or there is a desire for low maintenance. 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.

There is no electrical connection between these bars. Rotor induction motor an overview sciencedirect topics. 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. While the stator is equivalent to that of the squirrelcage motor, it has a set of windings on the rotor which are not shortcircuited, but are terminated to a set of slip rings. These motors are having the difference in rotor construction. It is called a squirrel cage motor because the rotor inside of it known as a squirrel cage rotor looks like a squirrel cage. Difference between squirrel cage and slip ring motors. Difference between slip ring motor with conventional drive and squirrel cage motor with variable speed drive. Their sole purpose is to allow resistance to be placed in series with the rotor windings while starting figure below. The main difference between slip ring and squirrel cage induction motor is the rotor construction. The construction of stator for any induction motor is almost the same.