A linear induction motor lim is a specific type of alternating current ac motor designed to produce motion in a straight line. Design and control of the induction motor propulsion of an. We know that t he speed of the induction motor is given by, from the above equation, the speed of the motor can be controlled by changing supply frequency and by changing number of poles in the stator. This theory was used to analyze twophase induction mo tors in 1969 2, linear induction motor in 1979 3, threephase squirrelcage induction motor with concentric winding in 1991 4, study of saturated induction machines in 1992 5, and fi. For instance, bombardier used laminated back iron instead of the integral back iron, which could improve the acceleration and deceleration performance of.
Linear induction motor having a slotted magnetic field structure wound with a multiphase winding having legs which extend in the slots. The legs are disposed in at least two layers in the slots and interconnected by pairs in each layer whereby all slots contain the same number of layers. The induction motor has two sets of windings copper or aluminum wire coiled to form electromagnets. An induction motor efficiency test program was undertaken by the north carolina alternative energy corporation to form an independent basis for recommending energy efficient motors to industry in. Ibrahim and others published modeling of induction motor based on winding function theory to study motor under statorrotor. Analysis of the endwinding cooling effects in tefc induction. Nov 11, 2011 the linear induction motor is designed for high speed operation. List and describe the more commonly used equipment in an electric substation. Analysis of the endwinding cooling effects in tefc. 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. 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. In the electrical model, the voltage, v, and the slip, s, determine the rotor current.
Differentiate between the various types of generating electric power stations. Pdf analysis of a concentrated winding induction machine. In that apparatus, mechanical rotation is obtained from mechanical rotation, therefore it is a kind of rotating induction clutch. The rotor will constantly be turning to align its magnetic field with that of the stator field. A stator winding is placed in the stator of induction motor and the three phase supply is given to it. That is why such motors are known as induction motors.
If you continue browsing the site, you agree to the use of cookies on this website. Motor analysis block diagram induction motor starting can be analyzed using electrical, mechanical, and thermal models which interact as diagrammed in figure 1. The basic idea of an electric motor is to generate two magnetic fields. Presentation on induction motor linkedin slideshare. Squirrel cage wound rotor with slip rings the rotating magnetic field the basic idea of an electric motor is to generate two magnetic fields. 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. An induction motors rotor can be either wound type or squirrelcage type. Induction motors are commonly used in numerous industrial applications. Analysis of a concentrated winding induction machine for adjustable speed drive applications part 1 motor analysis article pdf available in ieee transactions on energy conversion 64. This paper proposes a novel technique to improve the performance of induction motor. The summation of all torques acting on the motor shaft comprises the mechanical model.
This three phase winding is supplied by three phase ac supply. The slip ring 3phase induction motor is in progress by including resistances, thus the slip ring induction motor s stator winding can be associated in star otherwise delta form. The alternating current ac induction motor is one of the most rugged and most widely used machines in industry. For the designed three winding induction motor, the space factor is 0. 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. The induction motor is made up of the stator, or stationary windings, and the rotor. A threephase induction motor problem enginuity systems. Whenever the stator winding is energized by 3phase ac supply, then it generates a rotating magnetic field rmf. Induction motor driving a centrifugal compressor advantages.
For conventional induction motor, the space factor will be around 0. High level on the phase input causes the motor current, motor winding in order to produce a voltage feedback compared with the programmed voltage of the dac. The auxiliary or start winding overlaps the main or run winding. Pdf construction of three phase linear induction motor. The model created by rmxprt will then be used as an input for empulse as a basis for performing more detailed analysis and for increasing the accuracy of the performance pre. Nov 27, 2019 the three phase induction motor is the most widely used electrical motor. Ordinary production of induction motors is usually based on standardized stator and rotor lamination which can be bought on the market from several lamination producers. Pdf partialparallelpathwinding starting of threephase induction motors is used in order to reduce the starting currents in hardload condition, as. Slot area is effectively utilized by the conductors. Jun 03, 2017 the slots on the periphery of stator core of the three phase induction motor carries three phase winding or stator winding.
Proposed induction motor winding arrangement working as a phase converter. Construction of three phase induction motor electrical4u. This paper presents design and analysis of a three phase induction motor drive using igbt. It is logical that the least expensive, lowest maintenance type. 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. A threephase induction motor problem this application note describes how to set up, solve, and analyze the results of a twopole, threephase induction motor using rmxprt. The slots on the periphery of stator core of the three phase induction motor carries three phase winding or stator winding. Model repair specifications for low voltage induction motors these model repair specifications are intended to cover routine repair and rewind of lowvoltage randomwound threephase ac squirrel cage induction motors. This provides the revolving field necessary to turn the rotor. Based on a conventional squirrel cage induction motor.
Pdf partwinding starting improvement of threephase squirrel. What is stator winding in a threephase induction motor. It is a 16 bit highperformance digital signal controller dsc. Design of a single sided linear induction motor slim using a user interactive computer program a thesis presented to the faculty of the graduate school university of missouricolumbia in partial fulfillment of the requirements for the degree master of science by sarveswara prasad bhamidi dr. It is logical that the least expensive, lowest maintenance type motor should be used most often. Current is induced in these bars because the rotor normally turns at speed which is slower than the synchronous speed. A lim operates under the same principles as its ac rotary motor counterpart, typically powered by a threephase voltage scheme with a.
Model repair specifications for low voltage induction motors. What are the types of windings used for induction motors. Induction motors horizontal and vertical weg electric machinery, wem, induction motors have been specifically designed and manufactured for the most severe industrial applications, such as heavy duty fans, pumps, refiners, compressors, crushers and grinding mill drives. That would allow you to calculate an approximate number of winding turns for each winding distribution alternative that you wish to consider. Winding type influence on efficiency of an induction motor przeglad. In a conventional round rotor induction motor the behavior of the machine is only needed to be calculated ov er one pole pi tch. Stator is also provided with a starting winding which is used only for starting purpose. In addition to the run or main winding, all induction singlephase motors are equipped with an auxiliary or start winding in the stator. This is power point presesentation of principle of operation of induction motor. 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. You should also make a dc measurement of stator winding linetoline resistance using a dmm.
Depending on rotor construction, induction motors are classified as. In order to avoid forced ventilation on the external motor frame, the fan of the prototype and the fan of the synchronous motors have been. 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. Nov 18, 2015 induction motor torquespeed characteristics figure 6. The three phases of the winding are connected either in. The transmission gear ratio i is designed such that the ev reaches its maximum speed at the maximum induction motor speed. As a voltage and a current is applied to the stator winding terminals.
A wound rotor or slip ring motor has a 3phase winding, similar to the stator winding. The three phase induction motor is the most widely used electrical motor. As a voltage and a current is applied to the stator winding terminals, a magnetic field is developed in the windings. A lim operates under the same principles as its ac rotary motor counterpart, typically powered by a threephase voltage scheme with a force that is produced by a moving magnetic field 1. The synchronous motor is driven at variable speed by a threephase sinusoidal static generator that is regulated in frequency and voltage. The 3phase set of currents, each of equal magnitude and with a phase. In fact, an induction motor can be treated as a rotating transformer i. Reduction of shaft voltages and bearing currents in fivephase induction motor. Pdf a general winding design rule for the polephase modulation ppm induction machine is proposed, and three different structures, such as. An induction motor can therefore be made without electrical connections to the rotor. The induction motor developed force on the ev driven wheels is expressed by mm t tn f r. Design of the proposed multifunctional induction machine. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. Pdf winding design, modeling, and control for polephase.
The linear induction motor is designed for high speed operation. Pdf modeling of induction motor based on winding function. In this thesis, the analysis of the dynamic response of a linear induction motor as an electromechanical system is done, accounting for all the governing equations implied in the process which are used to develop the corresponding simulation models. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. Power torque constant torque region constant power region speed base speed maximum speed. In the summer of 1885 he conceived the idea that two outofphase, but synchronized, currents might be used to produce two magnetic fields that could be combined to produce a rotating field without any need for switching or for moving parts. The starting winding is located 90 electrical from the main winding see fig. Linear induction motors are quite an engineering marvel, to convert a general motor for a special purpose with more or less similar working principle, thus enhancing its. The lims 3phase coil assembly can be directly connected to the ac line for single speed applications or to an adjustable frequency drive for variable speed control. Record all nameplate information for the induction motor.
Induction motors p3 typical torquespeed and powerspeed curves for a 4pole induction motor torque power p these curves are greatly affected by the rotor resistance r2 in our model. Induction motor free download as powerpoint presentation. Chapter 3 induction motor and different speed control methods page no 3. In general, the induction motor is cheaper and easier to maintain compared to other alternatives.
The efficiency of induction motor depends on different factors. By using a modified stator winding arrangement the efficiency has been. Modification of the structure or material of rp has influence on motor characteristics. Various induction motor speed control methods advantages. The magnetization current im flowing in the motors equivalent circuit fig. Sharma electric brakin abstractan effective and reliable fast braking i. Induction motor electromagnetic induction electric motor. There are two major components of an ac induction motor. In three phase induction motor, the power is transferred from stator to. When the windings in the stator are energized it induces current in the windings in the rotor this invisible force is call induction, learn about the concept of induction here.
May 31, 2019 a linear induction motor or lim is a special type of induction motor used to achieve rectilinear motion rather than rotational motion as in the case of conventional motors. Rewinding of motors pdf the information in this report and the good practice guide to maintain motor efficiency part 2 was. Electric motors are relatively simple mechanical devices, but rewinding the coils on a dc motor is a precise task that should. As its name indicates stator is a stationary part of induction motor. The stator consists of a series of wire windings of very low resistance permanently attached to the motor frame. I3 i2 i1 i0 current level %, current flowing in the winding of the motor. Winding design, modeling, and control for polephase modulation induction motors article pdf available in ieee transactions on magnetics 492. If you know the maximum flux density and the size of the air gap, you can calculate the airgap flux per pole. The magnetic field structure is subdivided into units of doublepole pitch length which are electrically. Asplitphase induction motor the stator of a splitphase induction motor is provided with an auxiliary or starting winding s in addition to the main or running winding m. It may be said that the predecessor of the induction motor is the baileys. Introduction to induction motor the engineering projects. Winding layout, single layer winding, induction motors, rewinding technique, three phase motor. In this post let us see what are the various methods to control the speed of induction motor.