The 3phase set of currents, each of equal magnitude and with a phase. The principle of operation of the induction machine is based on. Explain the rotor rheostat control of 3 phase slip ring. Also know about the qualities of slip ring induction motors. The value of slip in induction motor is can never be zero. Popularly, when receiving a pulse signal, the stepper motor will rotate a fixed angle namelystepping angle according to the direction set for the stepper motor. Working principle of an induction motor circuit globe. Proposed circuit diagram of the traction drive system using wrim traction rectifier. When the stator windings are supplied with threephase alternating current, a rotating magnetic field is generated between the stator and the rotor. Slip ring induction motor is made up from wound rotor and squirrel cage induction motor is made up from the squirrel cage rotor. Induction motor works on the principle of induction where electromagnetic field is induced into the rotor when rotating magnetic field of stator cuts the. Pdf design and analysis of drive system with slip ring induction.
The topic lies under the basic electrical and electronics engineering course that covers various other. Three phase slip ring induction motor my tech info. Why are there two different designs of rotor construction for induction motors. In the second section, i would be throwing light on the operation and working principle of wound rotor induction motor. A motor is an electromechanical device which converts electrical energy to mechanical energy. An induction motor is the most modest electrical machine from constructional point of view, in the majority of the cases. Oct 10, 2016 a wound rotor induction motor is also known as slip ring induction motor. Ppt induction motor powerpoint presentation free to. The principle of working of squirrel cage and slip ring induction motor is based on faradays law of electromagnetic induction. Induction motor seminar ppt, pdf report study mafia. In these type of motors, the rotor is simplest and most rugged in construction. The stator of slip ring induction motor is very much the same as that of the squirrel cage induction motor, but the construction of its rotor is very much different. Pdf this work has developed a steadystate and dynamic mathematical model of three phase slipring induction motors with external impedance.
Watch this video to understand the working principals of the three phase induction motors. The rotor will constantly be turning to align its magnetic field with the stator field. Working principle of an induction motor the motor which works on the principle of electromagnetic induction is known as the induction motor. As discussed earlier, a slip ring induction motor is an asynchronous motor, as the rotor never runs in synchronous speed with the stator poles.
Slip ring induction motor is one of the types of 3phase induction motor and is a wound rotor motor type. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. An887, ac induction motor fundamentals microchip technology. At noload, the slip is nearly zero slip ring induction motor working in the induction principle. This rotating magnetic field has a speed which is known as the synchronous speed. As the torrent of water dried up for the first time in thousands of years. The torque of the induction motor depends on the rotor resistance. But at the starting of the induction motor, starting current is very large which may damage motor windings. A woundrotor motor, also known as slip ring rotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external resistance.
The slip ring motor has very little application in industries. In slip ring induction motors the rotor is wound type. But the rotor construction differs with respect to the type of motor. Cylindrical laminated core rotor is wound like winding on the stator. The speed of rotating magnetic field is synchronous speed, n s r. Introduction types of electrical machines types of 3ph induction motor basic principle working principle compnents of induction motor application comparision between 1ph i. Compared to squirrel cage rotor the rotor construction is not simple. Stator winding can be either star or delta connected depending upon the design. In the induction motors used in lift and hoists, you will see a type of rotor called a slip ring rotor, whereas in most of the other applications you will see a simpler, squirrel cage type of rotor. As these motors have external resistance connected to its rotor circuit, the value.
The slip ring induction motor working in the induction principle. These motors have much higher efficiency than slip ring induction motors. Jan 15, 2014 watch this video to understand the working principals of the three phase induction motors. Starting of slip ring induction motor explained in an easy manner. But how does external resistance aid in better starting characteristics. Read here to know about the starting arrangement and the role played by the external resistances in obtaining better starting characteristics.
Synchronous motor working principle instrumentation tools. A simple explanation of squirrel cage induction motors. Thus, the basic induction motor becomes an induction generator. Induction motor works on the principle of electromagnetic induction. When the 3 phase supply is provided to the stator, a magnetic field is produced which rotates the rotor and motor starts.
What are the specific applications of squirrel cage and. Slip ring induction motor construction, working and its. The slipring motor or woundrotor motor is a variation. Ball and roller bearings are used to suit heavy duty, torublefree running. In short, it works based on the principle of electromagnetic induction. Let see the construction of squirrel cage induction motor. This article is devoted to slip ring induction motors. The stator is the outer component of the motor which can be seen. A slip ring is an electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. By putting resistance in series with the rotor windings, the starting current can be kept low while maintaining good starting torque. When three phase supply is given to the stator winding, a rotating magnetic field of constant magnetic field is produced. An induction motor can be defined as the ac electric motor device in which a power source fed by the alternating current with the help of a primary winding. As these motors have external resistance connected to its rotor circuit, the value of starting current is adjusted or kept minimum, by increasing the resistance of the rotor circuit.
Motor runs smoothly as the magnetic hum is reduced b. Because of various advantages like low initial current, high starting torque, and improved power factor, it is used in applications that require high torque, cranes, and elevators. A slip ring can be used in any electromechanical system that requires rotation while transmitting power or signals. For induction motors a very important parameter is the slip of the motor the slip, s, defines the relative speed difference between synchronous speed and rotor speed and is given by. While slip ring induction motors also known as woundrotor motor arent as popular as. It is very commonly used in industries because it is very cheap, robust, efficient, and reliable. The rotor is separated from the stator by a small airgap which ranges from 0.
The rotor winding terminals are connected to three slip rings which turn with the rotor. The rotor will constantly be turning to align its magnetic field with that of the stator field. Adjusting the resistance allows control of the speedtorque characteristic of the motor. The stator of an induction motor is, in principle, the same as that of a synchronous motor or. Stepper motor is an actuator transforming electric pulse into angular displacement. The electromagnetic induction is the phenomenon in which the electromotive force induces across the electrical conductor when it is placed in a rotating magnetic field. This cooling type corresponds to the design of a surfacecooled motor with a housing featuring cooling fins and an external fan mounted on the shaft. Slip ring induction motor working principle electrical mastar. I will tell you about the construction of wound rotor induction motor in the first section. A motor with only armortisseur windings is called an induction motor.
If instead of taking mechanical power from the rotor, the rotor is driven by a prime mover such as the wind, it can be moved faster than the synchronous speed and starts producing electrical power instead of consuming it. The basic idea of an electric motor is to generate two magnetic fields. Explain the rotor rheostat control of 3 phase slip ring induction motor. We can react very quickly due to a comprehensive stock of slip ring motors in a power range up to 15000 kw. Explain starting methods of 3 phase induction motor. Starting and control of slipring induction motors5 97 the use of wound motors is on the wane, for reasons of inherent advantages of a squirrel cage motor over a wound motor and the availability of static drives which can make a squirrel cage motor perform the same duties as a wound motor and even better. Advantages and disadvantages of slip ring induction motor. The induction motor is started by itself that we know. Jul 25, 2019 squirrel cage induction motor working principle. When a 3 phase supply is given to the stator winding it sets up a rotating magnetic field in space. A slip ring induction motor can be started with external resistance added in its rotor circuit. Squirrel cage wound rotor with slip rings the rotating magnetic field.
The surfacecooling principle in slip ring induction motors ic 411 the standard threephase slip ring induction motor in protection class ip 55 has ic 411 cooling. With neat diagrams explains the working of any two types of starters used for squirrel cage type 3 phase induction motor. What is the working principle of slip ring induction motor. Most of the industries prefer these type of motor due to less maintenance cost, higher efficiency, and their lightweight construction. The construction of a stator is the same for both the squirrel cage and slip ring induction motor. Free download induction motor seminar ppt, pdf report. Working principal of three phase induction motor electrical. Induction motor basics, single phase and three phase. The slip ringsbrushes allow external resistors to be connected in series with the winding. Wound rotor induction motor as the slip power recovered can be used to. Maximum starting can be attained in the slip ring motor compared to squirrel cage motor by inserting an external resistance in each phase of the rotor circuit and cutting the resistance during starting speeds can be adjusted in the case of slip. When two unlike poles are brought near each other, if the. Enter your email below to receive free informative articles on electrical.
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. A 3 phase induction motor has two main parts i stator and ii rotor. Wound rotor induction motor the engineering projects. Sep 18, 2018 induction motors have been ruling the industrial world for many decades.
The slip ring induction motor could be used for industrial wires where variable speed and high starting torque are prime requirements. These motors are usually started with full line voltage applied across its terminals. Induction motors have been ruling the industrial world for many decades. Slip ring motor manufacturer menzel provides shortterm availability and adaptation, applicationspecific requirements and worldwide logistics. Jun 01, 2018 slip in induction motor is the relative speed between the rotating magnetic flux and rotor expressed in terms of per unit synchronous speed. A 3 phase induction motor can be used for different applications with various speed and load requirements. The slip ring rotor was developed after a decade or so. Slip ring motor fundamentals brighthub engineering. Synchronous motor mainly runs on principle of magnetic locking between rotor and rmfrotating magnetic field. Starting of slip ring induction motor explained in an easy. Learn more about the construction and operation of a slip ring induction motor. In the induction motors used in lift and hoists, you will see a type of rotor called a slip ring rotor, whereas in most of. The tendency of the rotor teeth to remain under the stator teeth due to direct magnetic attraction is reduced. By putting resistance in series with the rotor windings, the starting current can be kept low while mainta.
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