Pdf design and control of the induction motor propulsion of. Induction motor working principle when a threephase stator winding of an induction motor is connected to the ac supply, current starts flowing in the stator conductors. This paper explores the construction process of a linear induction motor lim, the basic concepts behind key aspects of linear induction machines construction and the testing process of a working. These are also called as asynchronous motors, because an. But here in induction motor only the stator winding is fed with an ac supply. Lecture 6 three phase induction motors cairo university. This is the basic working of the induction motor, whether its a single phase or 3 phase induction motor. Motor speed relationship the synchronous speed of an ac motor is the speed of the rotating magnetic field set up by the stator winding synchronous speed rpm 120 x frequency divided by the number of poles. The rotor is wound 3phase for as many poles as the stator and is shortcircuited. The major difference between them is that transformer is static in nature i. A portion of rotating magnetic field in a threephase. An induction motor is an ac electric motor in which the electric current in the rotor of electric motor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. In a twopole motor, the stator has one north and one south pole at any time, and the rotor needs to turn one full rotation or close to that for each cycle.
The rotor of an induction motor can be a squirrel cage rotor or wound. Other members of the family are the directcurrent dc motor or generator, the induction motor or generator, and a number. Based on the ev desired performances, the induction motor optimal power can be calculated. The motor is mounted in a test rig that allows one to control the torque applied to the motor shaft and to measure both rpm and torque. The induction motor, which is the most widely used motor type in the industry, has been favored because of its good selfstarting capability, simple and rugged structure, low cost and reliability, etc. You should also make a dc measurement of stator winding linetoline resistance using a dmm. These are also called as asynchronous motors, because an induction motor always runs at a speed lower than synchronous speed.
These motors include shaded pole the split stage, and capacitor motors. The principle of induction is a way of proving that pn is true for all integers n. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. The working principle and types of single phase induction motors have. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Fall 2005 ee595s electric drive systems 36 the plan continued achieving 14. 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 stator works as the primary while the rotor works as the secondary. Working principle of 3 phase induction motor, three phase induction motor working operation theory, types of induction motor induction motor working principle pdf. Single phase induction motor the singlephase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills, compressors, pumps, and so forth. An electrical motor is an electromechanical device which converts electrical energy into mechanical energy. The stator and rotor are two essential parts of the motor. Nov 27, 2019 thus from the working principle of three phase induction motor, it may be observed that the rotor speed should not reach the synchronous speed produced by the stator.
The singlephase motor stator has a laminated iron core with two windings arranged perpendicularly. For example, in an induction motor, it may be as high as 3050 % of rated current whereas it is only 15% of rated current in a transformer. So, this document provides information about single phase induction motor, constructionstator, rotor, working principle, types of single phase induction motors, starting methods of single phase induction motors, and applications of single. There basically 2 types of induction motor depending upon the type.
The difference is that, in the case of the induction motor, the secondary windings can move due to the rotation of the rotor the secondary winding of the im, the induced voltage in it does not have the same frequency of the stator the primary voltage 3192014 emdii induction motor design. Electromagnetical model of an induction motor in comsol. Let a be an integer, and let pn be a statement or proposition about n for each integer n. The speed of an induction motor is given as n 120fp 1s. Dec 23, 2016 working principle of three phase induction motor induction motor how does an induction motor workan electrical motor is such an electromagnetically device which converts electrical energy into a. As the supply given to the stator winding, flux will generate in the coil due to the flow of current in the coil. An induction motor is the most modest electrical machine from constructional point of view, in the majority of the cases. This is similar to a transformer, whose secondary is rotating and shortcircuited. Construction, types and principle of operation of 3phase induction motors. When a three phase supply is given to the three phase stator winding, a rotating magnetic field of constant magnitude is produced as discussed earlier. So obviously the speed of an induction motor can be controlled by varying any of three factors namely supply frequency f, number of pole p or slip s. Working principle of an induction motor the motor which works on the principle of electromagnetic induction is known as the induction motor. When three currents pass through these windings at an angle of 120 degrees a rotating magnetic field is generated. Induction motors an induction motor has two magnetically coupled circuits.
In essence, the objective of field orientation is to make the induction motor emulate the separately excited dc machine as a source of adjustable torque. An induction or asynchronous motor is an ac electric motor in which the electric current in the rotor needed to produce torque is induced by electromagnetic induction from the magnetic field of. 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. The induction motor is made up of the stator, or stationary windings, and the rotor. These types of motors are known as selfstarting induction motors. The induction motor and other alternating current motors, their theory and principles of design by behrend, bernard arthur, 1875publication date 1921 topics. Basics of induction motors basics of electrical engineering. The main methods employed for speed control of induction motors are as follows. Scroll to the bottom to watch the youtube tutorial on this article the induction motor is the most common type of electrical motor used in industry, and its used in pretty much everything, from elevators. Thus, as an electrical and electronics engineer or hobbyist we must know a few basic concepts about these types of machines we use regularly in our life. Electromagnetical model of an induction motor in comsol multiphysics iv we reserve all rights in this document and in the information contained therein. Working principle of induction motor semiconductor for you.
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. A 480v, 60 hz, 6pole, threephase, deltaconnected induction motor has the following parameters. Thus after the study of ac drive working principle, it becomes possible to control the speed of ac motor as well as to conserve the electrical energy, as we know that the energy conservation has become an important subject to all over the world. Jul 26, 2017 but the rotor never catches up the relative speed. A 3 phase induction motor derives its name from the fact that the rotor current is induced by the magnetic feild, instead of electrical connections. The basic idea of an electric motor is to generate two magnetic fields. 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. Most induction motors are either twopole or four pole. 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. The 3phase set of currents, each of equal magnitude and with a phase. What is common to all the members of this family is that the basic physical process involved in their operation is the conversion of electromagnetic energy to mechanical energy, and vice versa. The block uses the threephase input voltages to regulate the individual phase currents, allowing control of the motor torque or speed. In order for the stator filed to induce a current in the rotor circuit, the rotor must turn slower than synchronous speed such that faradays law of induction holds and the flux cuts across the rotor windings.
A 3 phase induction motor can be used for different applications with various speed and load requirements. But the three phase motor has a wider use in industries and homes. Principle of operation of induction motor eeeguide. Induction motor testing and evaluation summary as energy costs rise, more emphasis is being placed on determining the health of large inductive motors. Motor current monitoring and analysis mcsa is a straight forward tool to diagnosing problems with large inductive motors. It can be of two types, single phase induction motor or three phase induction motor. Woundrotor induction motor the magnetizing branch can not be neglected i0 may be 40% of ip due to the air gap for motors greater than 2 hp, the magnetization branch can be shifted to the input terminals for a motor running at a slip s, the rotor speed is ns1s this will modify the values of e1, i1, e2 and i2. Free download induction motor seminar ppt, pdf report. Working principle of an induction motor circuit globe. Thus from the working principle of three phase induction motor, it may be observed that the rotor speed should not reach the synchronous speed produced by the stator. If the speeds become equal, there would be no such relative speed, so no emf induced in the rotor, and no current would be flowing, and therefore no torque would be generated. In dc motor, one supply is given to the stator and another to the rotor through brush arrangement. For 60 hz systems, a two pole induction rotor will run anywhere from 3500 to 3600 rpm or about 5860 turns per second. 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.
Basic construction and operating principle like most motors, an ac induction motor has a fixed outer portion, called the stator and a rotor that spins inside with a carefully engineered air gap between. The speed of this rotation magnetic field is synchronous speed n s r. An887, ac induction motor fundamentals microchip technology. They run at a constant speed from noload to the full load. It is logical that the least expensive, lowest maintenance type. An ac engine is an electromechanical device that converts electric energy into mechanical motion throughout the shifting of the frequency as well as the usage of electromagnetism. The first industrial motors of this type were constructed at the end of the nineteenth century and soon gained the favor of users who appreciated their raggedness, simplicity and relatively low manufacturing cost compared to dc commutator motors. Differentiate between the various types of generating electric power stations. Induction motor basics, single phase and three phase.
The concept of field orientation, proposed by hasse in 1969 and blaschke in 1972, constitutes the most important paradigm in the theory and practice of control of induction motors. It is made up of a number of stampings, which are slotted to receive the windings fig. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. Induction motor seminar ppt, pdf report study mafia. The stator of an induction motor contains 3 single phase windings. This paper deals with a methodology for presizing the induction motor propulsion of an electric vehicle ev. Induction motors are the most commonly used motors in most of the applications. The principle of operation of induction motor figure 9.
To understand its working principle, lets take a look at its structural parts. All we need to do is to keep daxis stator current constant. Introduction to induction motor the engineering projects. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. 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. Induction motors ppt transformer electrical engineering. Introduction types of electrical machines types of 3ph induction motor basic principle working principle compnents of induction motor application comparision between 1ph i.
Single phase induction motor singlephase induction motors are used such as air conditioners, ceiling fans, washing machines, and refrigerators. Induction motor data calculates the inductances and resistances of the well known equivalent circuit of the induction motor from the nameplate parameters. A motor with only armortisseur windings is called an induction motor. Due to this current, a rotating magnetic field of constant amplitude and a constant speed is set up in the air gap between stator and rotor. Nov 03, 2019 an induction motor also known as an asynchronous motor is a commonly used ac electric motor. The rotor will constantly be turning to align its magnetic field with that of the stator field. Designing of three phase squirrel cage induction motor for. Introduction to induction motor instrumentation and. This is because does not require any starting device i. Induction motor working principle your electrical guide. The induction motor is an electromechanical device which successfully converts electrical energy to mechanical. Induction motor works on the principle of induction where electromagnetic field is induced into the rotor when rotating magnetic field of stator cuts the. An induction motor also known as an asynchronous motor is a commonly used ac electric motor.
List and describe the more commonly used equipment in an electric substation. An induction motor consists essentially of two main parts. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. Working principle of 3phase induction motor electrical. The motor which works on the principle of electromagnetic induction is known as the induction motor. Synchronous speed means the speed of the rotating magnetic field in the stator. The construction of the induction motor is robust in nature. Dec 25, 2014 now here is the key thought you must have to understand the induction motor working principle and why there is no pole slipping. 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. Pdf construction of three phase linear induction motor. To get a good understanding of the working principle of a three phase. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. When threephase stator winding of an induction motor is energized from a 3 phase supply, a rotating magnetic field is set up which rotates around the stator at synchronous speed ns.
Induction motors and transformers both im and transformer works on the principle of induced voltage transformer. It has been more than a century since the principle of the operation of induction motors was discovered. Chapter 1 principles of operation of synchronous machines the synchronous electrical generator also called alternator belongs to the family of electric rotating machines. This rotation of field is known as the synchronous speed. Record all nameplate information for the induction motor. Single phase induction motor 1introduction the singlephase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills, compressors, pumps, and so forth. Advantages and disadvantages of 3 phase induction motors. Singlephase induction motor threephase induction motor singlephase induction motor there are probably more singlephase ac induction motors in use today than the total of all the other types put together. Induction motors are the most commonly used motors in many applications.
The induction motor block implements a threephase induction motor. In the case of three phase ac alternating current operation, the most widely used motor is a 3 phase induction motor, as this type of motor does not require an additional starting device. How does a threephase alternating current induction motor work. There are two basic reasons for the use of singlephase motors rather than 3phase motors. The working of the threephase induction motor is based on the principle of electromagnetic induction. Induction motor problems and solutions pdf 3 phase induction motor pdf three phase induction motor the wound rotor induction motor speed control of induction motor three phase induction motor diagram blocked circle diagram of an induction motor speed control of induction motor by vf method single phase induction motor pdf free download speed control of three phase induction motor with. When a rotating magnetic field sweeps across the two windings, equal e. An electrical motor is a device that has brought about one of the biggest advancements in the fields of engineering and technology ever since the invention. Jul 26, 2017 it can be of two types, single phase induction motor or three phase induction motor. Find out here with this article on induction motors.