A singlephase motor is a rotating machine that has both main and auxiliary windings and a squirrelcage rotor. Ppt induction motor powerpoint presentation free to. Introduction to induction motor the engineering projects. Threephase ac induction motors are widely used in industrial and commercial applications. There are two types of induction motors, one is named as single phase induction motor, while the second one is named as 3 phase induction motor. Induction motor basics, single phase and three phase. Induction motor seminar ppt, pdf report study mafia. The single phase induction motor is more subtle and less efficient. Nov 07, 2011 stator it is the stationary part of the motor.
Stator has three main parts outer frame it is the outer body of the of the motor. The most common type of ac motor being used throughout the work today is the induction motor. The main purpose of controlling the speed of three phase induction motor is to save unwanted energy. The stator carries a 3 phase winding called stator winding while the rotor carries a shortcircuited winding called rotor winding. The very first thing that you should do before starting any type of maintenance on a motor is a visual inspection, a lot of times the trouble can be found just by looking, because if the problem is that bad then it should be very obvious by observation. It will start rotating in reverse direction and so does the rotor. Three phase induction motors authorstream presentation. Fault identification of 3 phase slip ring induction motor free download as powerpoint presentation. It consists stator winding it is housed on the motor frame.
Learn what a three phase induction motor is, how it is constructed, and its working principle. The rotor also carries star or delta winding similar to that of stator winding. The rotor will constantly be turning to align its magnetic field with that of the stator field. As previously, we have covered a lot of important topics. Hello everyone, i am niko and, in this instructables i will show you, how to rewind and renew old three phase electric motor. This type of motor has a major use in the different industrial applications due to numerous benefits such as higher efficiency, reliable cost, minimum maintenance and selfstarting feature. The thermal overload is supplied as a separate item. Since a stator and its winding of three phase induction motor is the same as that of a synchronous motor. There are two types of induction motors, one with wound type rotor, also called slipring motor and another one with squirrelcage rotor. Like any electric motor, a 3 phase induction motor has a stator and a rotor. As induction motors are widely being used, their speed control may be required in many applications.
Applications of three phase induction motors of size varying from half a kilowatt to thousands of kilowatts are numerous. Three phase induction motor the induction motor that runs on a three phase ac supply is known as a threephase induction motor. 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, absence of commutator and good speed regulation. It comprises an enclosure in steel or plastic, a contactor, start contact, link wires and stop start buttons. Fault identification of 3phase slip ring induction motor. As the rotor conductor is short circuited current flows through them. Ppt threephase induction motor electrical engineering ee. The starter energizes the motor and thus the motor is started. Sep 27, 2016 induction motor is an ac electric motor, having a stator and a rotor just like other motors, but the working principle is a little different which would be discussed further. These motors are selfstarting and use no capacitor, start winding, centrifugal switch or other starting device.
The synchronous speed is independent of loading condition and it is constant. Many single phase motors having two windings can be viewed as two phase motors, since a capacitor is used to generate a second power. It certainly leads to the best performance and high efficiency of the induction motor. Frame provides mechanical support to the stator and rotor. Today we are going to made available a powerpoint presentation file for all. They are found everywhere from a small workshop to a large manufacturing industry. The three phase induction motor is the easiest motor of this type to understand so these notes start with that type. If you are searching for rewinding of one phase motor you can find it here. Speed control of three phase induction motor ppt play ppt. If we interchange any two phases of the ac supply, we will get new phase sequence, then the direction of rotating magnetic field in three phase induction motor will reverse. By far the most commonly used ac motor is the induction motor. The supply is given to the rotor resistance starter.
Hardware implementation the 3 phase supply is given to the equivalent circuit of the slip ring induction motor which is formed using chokes. It protects the inner part of the machine stator core built up of high grade silicon steel. Be careful it can hurt to tangle with a three phase motor. The primary focus of problems in a three phase induction motor is in their stators and their supports. Ppt threephase induction motor electrical engineering. One of the most important topic for electrical engineers. Supplying of both main and auxiliary windings enables the singlephase machine to be driven as a twophase machine. As shown in equation, the developed torque depends on the air gap power and synchronous speed. The braking is the process of reducing the speed of an induction motor. Therefore, the direction of rotation of a 3 phase induction motor can be reversed by interchanging any two of the three motor supply lines.
Jun 10, 2017 in this video basic of construction and working principle of 3 phase induction motor is explained with the help of 3d animation. Induction motors ppt transformer electrical engineering. View and download powerpoint presentations on three phase induction motor ppt. Find powerpoint presentations and slides using the power of, find free presentations research about three phase induction motor ppt. A variable frequency drive vfd is used to control the speed of motor with the primary voltage control method. The method is characterized by less investment, simple equipment and small quantity. Different speed control methods of induction motor are explained below. It becomes a current carrying conductor in magnetic field and start rotating. Only the stator winding is fed from the 3 phase supply. Feb 15, 2018 a simple explanation of a 3 phase induction motor. These are of two types, squirrel cage and slip ring motors.
Directonline starting this kind of starting mode is the most basic and simplest in the motor starting. There are two basic reasons for the use of single phase motors rather than 3 phase motors. Windingrotor arrangements for 3 phase induction machine three phase slip ring induction motor. The three phase induction motor is the most widely used electrical motor. Download 3 phase induction motor powerpoint presentation. View 3 phase induction motor ppts online, safely and virusfree. The rotor of three phase induction motor consists of a cylindrical laminated core with parallel slots that can carry conductors. In braking, the motor works as a generator developing a negative torque which opposes the motion the braking is mainly classified into three types i. The most common type of three phase induction motor is the squirrel cage type. As we shall see, the rotor in a 3 phase induction motor runs in the same direction as the rotating magnetic field. The starting methods of three phase induction motor generally are directonline starting, reducedvoltage starting and soft starter. These stator and rotors are made up of highmagnetic core materials with less hysteresis and eddy current losses. Maintenance and troubleshooting three phase induction motor. Introduction threephase induction motors are the most common and frequently encountered machines in industry simple design, rugged, lowprice, easy maintenance wide range of power ratings.
For reason of economy, most houses, offices and also rural areas are supplied with single phase a. This presentation file is prepared by one of my friend taking help from different sources. These are usually caused by broken bars or broken end rings, rotor misalignment and imbalance. Parts of an induction motor three phase induction motor. Induction motors are most commonly run on single phase or three phase power, but two phase motors exist. Dec 29, 2017 threephase induction motors are the most common and frequently encountered machines in industry simple design, rugged, lowprice, easy maintenance wide range of power ratings. Three phase induction motor consists of a stator and a rotor, and there is no electrical connection between these two. Rotating magnetic field in 3 phase induction motor your.
Scribd is the worlds largest social reading and publishing site. This final thesis will mostly be dedicated to induction motors but also to synchronous permanent magnet and reluctance motors. Directonline dol motor starter description the direct on line motor starter dol is designed to switch a single or three phase induction motor at rated voltage. For a three phase supply, this can be done by interchanging any two of the three lines. The conductors are heavy copper or aluminum bars fitted in each slot and shortcircuited by the end rings. The rotor winding terminals are connected to three slip rings which turn with the rotor. The stator consists of three phase windings overlapped with one another at 120 degree phase shift. How an induction motor works by equations and physics. Well, every electrical domain engineering students are aware of 3 phase induction motor. While materials and insulation systems have changed, the basic principles and operation of an electric. A successful salesman for general electrics motor division once remarked to one of your instructors that, when asked by a customer how a motor. The 3 phase set of currents, each of equal magnitude and with a phase.
The rotor is separated from the stator by a small airgap which ranges from 0. The basic idea of an electric motor is to generate two magnetic fields. Threephase induction motors are the most common and frequently encountered machines in industry simple design, rugged, lowprice, easy maintenance wide range of power ratings. Threephase induction motor protection systems and its. The magnetic field in the air gap from the voltage applied to the stator. A 3 phase induction motor has two main parts i stator and ii rotor. A wound rotor or slip ring motor has a 3phase winding, similar to the stator winding. The electric motor has its name derived from the fact that the rotor assemble resembles the wheel of a squirrels cage. Dec 23, 2014 principle of operation a rotating magnetic field rmf is set up in the stator when a 3 phase supply is given. The leading causes of failures are superheating, imperfections in the isolation, mechanical bearings, and electrical failures.
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