It is comprised of two parts, the primary and secondary, which interact with one another only when power is. Engineers who design electric machines need simulation tools that can be employed for quick, accurate product development. It is comprised of two parts, the primary and secondary, which interact with one another only when power is applied. 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.
The maximum starting thrust force of this linear induction motor is approximately 180 n. Jul 15, 2019 a linear motor is effectively an ac induction motor that has been cut open and unwrapped. Slim is by far the most widely used in linear induction motor. You can be easy to arrange the copper rail and the magnet to the piece of wood. Aug 23, 2016 using the shop products, i tried to make the principle of the linear motor car. The design of the linear induction motor is largely dependent on a combination of two items. Mec design and construction of a pulsed linear induction motor. For linear induction motors, the primary consists of a steel lamination stack with windings, and the secondary is a conductive plate typically aluminum or copper with a steel backing. This tutorial will introduce the user to the fundamental electrical and mechanical principles of ac electric induction motor design and application. Performance analysis of the linear induction motor for the. The linear motor has a long history similar to that of a rotating machine.
Each primary is installed along the entire length of the launch structure, but is divided into sections. Het electric motor massively boosts power, torque and. In a traditional electric motor, the rotor rotating part spins inside the stator static part. The hercules winding design maximizes the amount of copper over the standard ironless coil arrangements, thereby achieving high motor constant. Linear induction motor working principle your electrical guide. 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. A linear motor is an electric device that provides an electromagnetic force by causing a direct and linear movement to a subject, and a structure in which a cylindrical. Linear induction motors can achieve speeds in excess of 1800 inches per second 45 ms and accelerations in the range of 3 to 4 gs. May 31, 2016 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. What is a linear induction motor and how does it work. In this paper, singlesided linear induction motor slim for driving the elevator system is designed. 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 versatility of operation.
Traditional design of cage rotor induction motors ronald g. Standard lims can produce forces in the range of 720 lbs 3200 n at a 3% duty cycle. A parallel history of linear induction motors with applications in linear. Design, construct, and test a linear induction motor lim powered by a threephase voltage input rotate a simulated linear track and cannot exceed 1,200 rpm monitor speed, output power, and input frequency controllable output speed 7 5. Singlesided linear induction motor slim,equivalent circuit model, linear machine design. In this paper a mathematical model of tubular linear induction machines tlim with hollowed induced part is recalled. A more complete list of events that marked the induction motor history follows. Lets break this down and make it simple, linear induction motor lim theory is most easily understood as a rotary motor that has been cut and unrolled to generate linear motion, instead of rotary motion. A linear induction motor lim is an alternating current ac, asynchronous linear motor that works by the same general principles as other induction motors but is typically designed to directly produce motion in a straight line. A linear induction motor is basically a rotating squirrel cage induction motor.
Design of singlesided linear induction motor used in elevator ijsea. The rotor takes the form of a moving platform known as the secondary. The basic design and construction of a linear induction motor is similar to a three phase induction motor, although it does not look like a conventional induction motor. As the figure shows, thrust force increases as the power supply frequency gets higher. Elements of linear induction motor design for urban transit ieee. This paper proposes an analytical model to design and investigates the doublesided linear induction machine with a ladderslot arrangement employed on the secondary mover.
In the present paper, the mover speed control of a linear induction motor lim using a sliding mode control design is proposed, considering the end effects. Simple linear motor how to make a simple linear motor. Hi friends, in this article, i am going to describe the linear induction motor working principle. Pdf this paper suggests and describes the methodology for the design of a linear induction motor which will accelerate the rotor aluminum. In the design of the induction motor, operational characteristics can be determined through a series of calculations. The first linear motor was conceived by wheatstone more than 100 years ago. Circular rail linear induction motor download pdf info publication number us6876122b2. Performing these calculations can help the engineer. We start by looking at current projects and plans, such as the us navys plans to make catapults and arrestors based on linear induction motors and nasas plans to raillaunch spacecraft the same way. Likewise, if the circular stator is cut into two sections and flattened, the motor becomes a doublesided linear induction motor dlim.
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. In the application example, the performance of low. Moreover, this method may be also used at a design optimization. Design and performance investigation of the doublesided linear induction motor with a ladderslot secondary abstract. This is interesting development of a conventional induction motor. It is special type of induction motor which gives linear motion instead of rotational motion as in the case of a conventional induction motor. It is special type of induction motor which gives linear. A small single stage pulsed coaxial linear induction motor was designed and constructed to verify the computational simulation used in its development, and to determine the feasibility of the operating concept at low voltages and energy inputs of 400 volts and of 25 joules respectively. A polyphase linear induction motor comprising a primary member having magnetic material formed with a polyphase winding and, for cooperating with the primary member, a secondary member comprising electrically conductive material backed by further magnetic material is so arranged that the working flux passes in low reluctance paths lying substantially in planes directed transversely of the motor. However, development of linear induction motor design unfortunately was not effective and use rotary motor design analogy. Mainly due to power electronics and digital control, the induction motor may add to its old nickname of the workhorse of industry the label of the racehorse of hightech.
This is because eddy currents in the aluminum sheet increase with higher power supply frequencies as shown in fig. Page 2 of provide a motor that is best suited to a particular application. Pdf speed control of linear induction motor using sliding. That is caused by the existence of the inherent characteristic of linear induction motors such as there are a longitudinal end effect and transverse edge effect. It performs linear motion instead of rotary motion as in a conventional 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. Linear induction motor working principle your electrical. It is a special purpose motor that is used for linear motors. The success of the motor will be determined by six different nonfunctional requirements, and overall by the control of rotation of a large diameter wheel that. A slim of specified parameters is designed using a userinteractive matlab program, and then compared to a similar tubular linear induction motor tlim.
Design and performance investigation of the doublesided. Nothing has changed, only the direction of motion has changed. Dec 04, 2018 survey paper presentation made in fall2018 for electrical machines. Mar 22, 2019 the thrust produced by a linear induction motor is a factor of the supplied voltage, the amount of slip, and the size of the air gap, as well as the influence of end effects. And because linear induction motors have lower efficiencies, cooling can have a measurable effect on the motors ability to produce thrust. Linear induction motor limo modular test bed for various. Design and performance analysis of single sided linear induction. Linear induction motor lim, is basically an advanced version of motor that is in use to achieve rectilinear motion instead of rotational motion as in ordinary. The variety of designs suited to different speeds, airgaps and reaction plates is extensive. A linear induction motor lim is an alternating current ac, asynchronous linear motor that works by the same general principles as other induction motors but is typically designed to. A study has been made on the design of the singlesided linear induction motors slims for the urban transit with the maximum speed of 70kmh. Lim is an advanced version of rotary induction motor which gives a linear translational motion instead of.
Linear induction motor a linear induction motor lim is an advanced version of rotary induction motor which gives a linear translational motion instead of the rotational motion. Harley and yao duan georgia institute of technology november, 2009. The main purpose of this project is to design and fabricate a linear induction motor lim that can generate motion and force in a linear direction. If we cut the stator of a polyphase induction motor and lay on a flat surface, it forms the primary of the linear induction motor system. 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. A linear induction motor lim is a specific type of alternating current ac motor designed to produce motion in a straight line. The linear induction motor is designed for high speed operation. Find linear induction motor design related suppliers, manufacturers, products and specifications on globalspec a trusted source of linear induction motor design information.
When selecting a linear induction motor lim it is important to understand the interaction between stator, reaction plate and airgap. In this type of motor, the stator and rotor are called primary and secondary respectively. 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. Performance analysis of the linear induction motor for the deepunderground highspeed gtx 202 maximum speed should be around 34. Design and performance analysis of proposed singlesided linear. The aim of this paper is to present the redesign method of an electromechanical actuator linear induction motor lim and to show advantages of the redesign. The redesign procedure involves the combined equivalent electrical circuit and the 2d finite. Linear induction motors can be manufactured in a wide range of force outputs, speeds, and footprints. A circular segmented rail element is disposed within the motor casing about the central axis. The thrust produced by a linear induction motor is a factor of the supplied voltage, the amount of slip, and the size of the air gap, as well as the influence of end effects. We also look at the speedway transport system, a novel approach that provides. Linear motors are electric induction motors that produce motion in a straight line rather than rotational motion. Design of singlesided linear induction motor science publishing. A linear motor is an electric device that provides an electromagnetic force by causing a direct and linear movement to a subject, and a structure in which a cylindrical rotary motor is developed linearly can be considered.
This article will provide you answers of various questions about the lim. The switched reluctance motor appears doomed to low energy efficiency. Design and construction of a pulsed linear induction motor summary in tro duction a t ypical coil gun con v erts electrical energy to linear kinetic b y using a wire w ound stator and electromec hanical principles to accelerate a ferromagnetic or wire w ound coil armature. Linear induction motor research brighthub engineering. Using the shop products, i tried to make the principle of the linear motor car. They are usually of the ac linear induction motor lim design with an active threephase winding on one side of the airgap and a. And because linear induction motors have lower efficiencies, cooling can have a.
A linear motor is effectively an ac induction motor that has been cut open and unwrapped. The stator is laid out in the form of a track of flat coils made from aluminum or copper and is known as the primary of a linear motor. The larger the motor power, the more severe this phenomenon. Linear labs makes some enormous claims about its innovative electric motor design. Vivek brahmbhatt already has explained very nicely the construction of lim. 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 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.
Simple method of linear induction motor redesign sciencedirect. This article is based on linear induction motor research, and the future technologies of linear induction motor. Force engineering ltd linear induction motor options. A linear induction motor is a developed version of cylindrical induction motor.
Design and construction of a pulsed linear induction motor figure 3. Normally lim is used to make a motion frictionless absolutely. The hercules series linear motor from mfm technology is a unique movingcoil design based on the ironless zero cogging principle. Linear induction motor is normally referred as linear motor. A study has been made on the design of the singlesided linear induction motorsslims for the urban transit with the maximum speed of 70kmh. I would just like to add some practical applications of lim. Of particular in terest to this study ho w ev er is the op eration of a. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects, whereas a conventional induction motor is arranged in an endless loop. Design criteria of tubular linear induction motors and. Design, analysis of linear induction motor based on. What about using linear induction motor design instead. Moreover the design criteria of a tlim with hollowed iron induced part are presented as well as the technological processes to be adopted and the choice of.
Circuit globe when power is supplied to the primary, magnetic flux develops and travels across the length. Each aircored linear induction motor has a primary winding consisting of a linear array of coaxial circular coils, and a secondary which is a cylindrical conductive sleeve concentric with the primary. It holds great promise, since it is not limited by irons saturation at field strengths around 1 tesla. Pdf construction of three phase linear induction motor. This approach provides a cheap and effective way of a lim development and production. The present invention is directed to an electric motor for rotating an object around a central axis. Multiple motors can be used in conjunction with each other to generate larger forces. Construction of a linear motor or linear induction motor. Performance analysis of the linear induction motor for the deepunderground highspeed gtx chanbae park, hyungwoo lee and ju lee abstract in order to develop a deepunderground great train express gtx in south korea, the specifications decision and development of a traction control system including an inverter and a. They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required.
Exp erimen tal system used to test the pulsed linear induction launc her concept. However, the direct current homopolar linear motor railgun is another high acceleration linear motor design. In traditional designs of 60 hz linefed induction machines, skin effect is represented by correction coefficients k. Survey paper presentation made in fall2018 for electrical machines. Better and better analytical models for steady state and design purposes. For singlesided assemblies, the reaction plate consists of 18in. 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. Linear induction motor lim theory is most easily understood as a rotary motor that has been cut and unrolled to generate linear motion, instead of rotary motion.