In general, the induction motor is cheaper and easier to maintain compared to other alternatives. Consider a single phase induction motor whose rotor is at rest. Performance of linear induction motors within an automated. For maglev applications, two specific configurations of these linear motors are considered that have been practically tested and applied. When a linear motor receives power for more than thirty 30 seconds, it is operating at a duty cycle of 100%. 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.
In the betatron, there is usually one pulsedpower primary input. Characteristics of linear induction motor considering material of. Force analysis of linear induction motor for magnetic. Linear induction motor electric motor rotation around a. The aim this researc h pro ject is to dev elop a linear induction motor system capable of op erating at 400 v olts with an initial energy of 25 j to in v estigate the lo w feasibilit y op erating concept and erify design pro cedure used in. Comparison of linear synchronous motors lsm and linear induction motors lim 20, 21 linear synchronous motor lsm taking into account the following. Baldor linear motors and stages steven engineering. Sizes vary from fractional horsepower to several thousand horsepower used for such applications as dieselelectric locomotives. Induction motor seminar ppt, pdf report study mafia. The case where the system dynamics are described by a set of linear differential equations and the cost is described by a quadratic functional is called the lq problem.
Study and design of a double sided linear induction motor. Pdf construction of three phase linear induction motor. Developing an efficient yet powerful linear induction motor lim is key to swissloops future as a sustainable hyperloop transportation company. The linear motor training system is a useful teaching tool for instructors who wish to demonstrate the basic principles of magnetism as applied to the operation of linear induction motors. That is why such motors are known as induction motors. Introduction trafficrelated problems are multiplying rapidly in the denselypopulated capital of the republic of korea. High grade control of linear induction motor drives by. A conducting rod moving in a uniform magnetic field the rod, velocity, and current are mutually perpendicular. Curren t w a v eforms pro duced b y the system in practice and theoretical sim ulation are compared to eac h other, in addition qualitativ ely observing an y motion of the armature coil.
Instead of producing rotary torque from a cylindrical machine it produces linear force from a flat one. Free download induction motor seminar ppt, pdf report. Linear induction motors e r laithwaite imperial college of science and technology london patent literature first mentions linear induction machines in 1890, only two years after the discovery of the rotary induction principle. Optimalairgap control of a linear induction motor for. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects, whereas a conventional induction motor is arranged. Mar 10, 2021 pdf this paper explores the construction process of a linear induction motor lim, the basic concepts behind key aspects of linear induction machines. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. Being a leader in linear motor design and manufacturing, baldor continually develops advanced products and innovations to meet a variety of linear motion applications. The electrical generator includes a tube assembly having a tube with an induction coil surrounding the tube and an induction magnet within the tube. The motors must be properly sized for the application so that they run within the rated operating conditions for the specific motor. Induction motors are the commonest type of motor and account for a very large proportion of heavy duty motors.
They may be obtained by cutting and unrolling the rotary induction machines to yield flat, singlesided topologies figure 5a, where the cage secondary may be used as such or replaced by. The electric motors in most case s are responsible for the proper functioning of the productive system. The secondary of the linear induction motor consists of a flat aluminium conductor with a. Apart from basic types of motors, several different types of motors have been developed with special features such as stepper motor, linear induction motor lim and others, designed according to the needs of the industry.
Service factor is a multiplier that indicates how much a motor can. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects. Abstractin this paper, a method of calculating the parameters of equivalent circuit model of linear induction motorlim is proposed based on numerical. Among many kinds of linear motors, linear induction motor lim is prefer for the urban railway. Linear induction accelerators 284 in the linear induction accelerator, the beam is a single turn secondary with multiple parallel primary inputs from highvoltage modulators. Exp erimen tal system used to test the pulsed linear induction launc her concept. Design of a single sided linear induction motor slim using a user interactive computer program 32 books linear induction motor 33 patents linear induction motor construction 34 secondary member for singlesided linear induction motor 35 linear induction motor 36. Instead of rotary motion in a three phase conventional. Comparison of observed data to regression model predictions 24 figure 12.
By using direct thrust control, position sensorless drive is available in linear metro and that can be used as a failsafe function of the vector control when. Developments of induction motors for superhigh speeds and high powers a parallel history of linear induction motors with applications in linear motion control has unfolded new and better methods of manufacturing and testing for induction machines integral induction motors. Linear induction motor, the following equations are used. Simplified perphase model of an induction motor 17 figure 9. These use a conductive plate on the moving load and work like a rotary induction motor, with a slip speed between the. Oct 01, 2015 design of a single sided linear induction motor slim using a user interactive computer program 32 books linear induction motor 33 patents linear induction motor construction 34 secondary member for singlesided linear induction motor 35 linear induction motor 36.
Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Apr 29, 2018 linear induction motor lim is an asynchronous motor, working on the same principle an induction motor works, but is designed to produce the rectilinear motion, unlike the rotary movement produced by a motor. Figure 2 motor power factor as a function of % fullload amperage overloaded motors can overheat and lose efficiency. In this paper, first the dynamic model of the linear induction motor with including end effects is represented. A doublesided linear induction motor dlim is a special type of induction motor which gives linear motion. Linear induction motor electric motor rotation around. There are different types of linear induction motors lims, among them, singlesided linear induction motors slims are widely used in transportation system. In fact, an induction motor can be treated as a rotating transformer i. For singlesided assemblies, the reaction plate consists of 18 thick aluminum backed by a 14 thick steel plate, and for doublesided assemblies the reaction plate is 18 thick aluminum or copper only. L r s and be the angular velocities of the magnetic field line frequency, rotor, and slip respectively.
Figure 1 shows the concept of a linear motor derived from a rotary motor. 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. Linear induction motor induction launc hers feasible within the scop e of a small undergraduate pro ject. Wo2015164941a1 linear induction generator using magnetic. In the case of threephase 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. Labvolt series by festo didactic linear motor training. Among many kinds of linear motors, linear induction motor lim is. Keywords drives, elevators, linear induction motor, power electronics. Nowadays, the vast majority of applications, that a linear motion is. It can also be used by students for determining the basic electrical characteristics of a linear induction motor and studying the dynamic behavior tractive force, acceleration, top speed of a linear. Design of a linear and non linear controller for induction motor design of lqr controllerthe theory of optimal control is concerned with operating a dynamic system at minimum cost. An induction motor consists essentially of two main parts. Passenger and cargo capsules need to be accelerated via some form of a highspeed linear accelerator and a lim is believed to be one of the best options for such a system. Levitation and rotation of this ring system is realized by the slim segments and requires a simultaneous, decoupled control of the generated thrust and normal forces.
In addition, many studies of dtc in linear induction motor drives are performed 1,3. Many motors are designed with a service factor that allows occasional overloading. There are different types of motors developed for different purposes. Optimalairgap control of a linear induction motor for korean. High grade control of linear induction motor drives publication no. They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required. It is made up of a number of stampings, which are slotted to receive the windings fig. Ppt linear induction motor powerpoint presentation free. 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. Ac induction motor high performance linear induction motor baldor provides industry with the widest range of linear motors, linear stages and controls. Nov 15, 2020 an electrical motor is an electromechanical device that converts electrical energy into mechanical energy. The model of lim with considering end effect had been proposed in.
The induction motor is made up of the stator, or stationary windings, and the rotor. The technology is not new but merely designed in a. Linear induction motor rotary, squirrel cage induction motor, split radially along its axis of rotation and flatten out is a linear induction motor that produces direct linear force instead of torque linear induction motor noncontacting, high speed, linear motor that operates on the same principle as a rotary, squirrel cage, induction motor. In addition, the number of longdistance commuters continues to increase as an increasing number of citizens moving to. In this type of motor, the stator and rotor are called primary and secondary respectively. Linear induction motor, traction system, electromagnetic analysis, power consumption 1. Synchronous velocity, r s v v 1s 1 pole pitch, 2 v s 2f 2 slot pitch, 1 2 mq 3 length of primary stator, l s 2s 4 2. It operates on the principle of which a conventional induction motor operates. Design of singlesided linear induction motor used in elevator. The university of texas at arlington, 2007 supervising professor. The linear induction motors for transport vehicles such as urban vehicles or trains, or for linear drives where they can replace the rotary electric machines, hydraulic or pneumatic equipment with linear movement. Pdf this paper explores the construction process of a linear induction motor lim, the basic concepts behind key aspects of linear induction machines. A linear induction motor lim is an advanced version of rotary induction motor which gives a linear translational motion instead of the rotational motion. Basically the con cept of the linear device consists in imagining a.
Survey paper presentation made in fall2018 for electrical machines. How an induction motor works by equations and physics. Finally, we designed a linear induction motor lim for a propulsion system, and we used the finite element method fem to analyze its performance as it travelled through deepunderground tunnels. Dc motors dc controls software linear stages linear motors engineering information duty cycle the duty cycle of a motor is defined as the time the motor receives power during a cycle divided by the total time of the cycle. 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. S l r the flux in the singleturn coil on the rotor surface is. Pdf equivalent circuits for singlesided linear induction. Mec design and construction of a pulsed linear induction motor. Ppt linear induction motor powerpoint presentation. Linear motors have been examined with threephase moving magnetic field models and insufficientlyresearch parts of the problem were interpreted as different models in the literature has been evaluated. Linear induction motors can be manufactured in a wide range of force outputs, speeds, and footprints.
They have merits such as the ability to exert thrust on the secondary without mechanical. Induction motor equations engn1931f spring 2017 2 let. Comparison of linear synchronous and induction motors. This video explains how a linear induction motor works. That must include duty cycle, speed, torque, and importantly cooling. A doublesided linear induction motor dslim is a special type of induction motor which gives linear motion instead of rotational motion, as in the case of conventional induction motor. The beam acts as a multiturn secondary because it is wrapped in a circle. Linear induction motor lim for hyperloop pod prototypes. If a rotary induction motor is compared with the linear induction motor, the lim requires a larger air gap and hence, the magnetising current is greater and the power factor and.
Lenzs law the direction of any magnetic induction effect is such as to oppose the cause of the effect. In this paper, the methodology for the design of a singlesided linear induction motor which will accelerate the secondary aluminum sheet with a specified mass. Performance analysis of the linear induction motor for the. The development of advanced linear induction motor. A linear induction motor lim is a noncontacting, high speed, linear motor that operates on the same principal as a rotary, squirrel cage, induction motor. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. The technology is not new but merely designed in a different form. In industrialized countries, induction motors are responsible for the 40% to 50% of energy consumption. The study was carried out to design a 3phase small linear induction motor that can travel at the speed of 1 meter per second when supplied 9. A linear motor is a conventional rotary motor whose stator, rotor and windings have been cut open, flattened, and placed on the guideway.
There are two basic reasons for the use of singlephase motors rather than 3phase motors. Linear induction motor slim segments implemented in a rotating ring system. Linear induction motor background alternating current ac electric motor powered by a three phase voltage scheme force and motion are produced by a linearly moving magnetic field used in industry for linear motion and to turn large diameter wheels 6 4. How an induction motor works by equations and physics introduction. 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. A single phase induction motor is inherently not selfstaring can be shown easily. The thrust velocity curve of the linear induction motor is similar to that of the speed torque curve of the rotary induction motor. Maglevcobra levitation vehicle and the required control to a secure and economic driving. Induction motors oriental motor pdf catalogs technical. Many induction motors are not designed to run at slow speeds with high torque. However, because of end effect, linear motors cannot run light normal induction motors are able to run the motor with a near synchronous field under low load conditions. This tutorial will introduce the user to the fundamental electrical and mechanical principles of ac electric induction motor design and application. Apr 21, 2016 linear induction motor background alternating current ac electric motor powered by a three phase voltage scheme force and motion are produced by a linearly moving magnetic field used in industry for linear motion and to turn large diameter wheels 6 4. Pdf design of a linear and nonlinear controller for.
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