Tubular linear induction motor analysis by using finite elements and current filament models. Development and performance of a linear induction motor. However, linear motors are not necessarily straight. Analysis and optimization of starting characteristics of. They performed optimization by using rsm to decrease motor weight and increase thrust. When modeling the linear or tubular device with the magnetic fields and the moving mesh physics interfaces, it is appropriate to use a customized linear periodic boundary condition. Its functioning principle is similar to that of the traditional induction linear motor. Figure 2 shows the model of the tubular linear induction motor and inscribes the. Numerous applications of lims can be found in industry today, one of the most interesting being high speed magnetic levitation railway systems. Pdf the current filaments cfm and the finite elements fem models for analyzing tubular linear induction motor tlim performances are. An axisymmetric model of the magnetic field of the tubular linear induction motor tlim for application to hydraulic capsule pipelines is developed using finite element method fem analysis. Used in many industrial and hightech fabrication applications, linear motors are an invaluable part for the fastest and most efficient processes.
They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required. The current filaments cfm and the finite elements fem models for analyzing tubular linear induction motor tlim performances are presented. Induction motors are the commonest type of motor and account for a very large proportion of heavy duty motors. Characteristically, a linear motors active section has ends, whereas more conventional motors are arranged as a continuous loop. Permanentmagnet based tubular linear motors should not be confused with tubular linear induction motors, which work on a. A semianalytical model of the double sided tubular linear induction motor dstlim is adopted for the optimization of the thrust force of the stages of. How an induction motor works by equations and physics. A linear motor is an electric motor that has had its stator and rotor unrolled thus instead of producing a torque it produces a linear force along its length. Fem analyze of a simple module of the linear tubular stepping motor.
Leonardo electronic journal of practices and technologies issue 23, julydecember 20 issn 15831078 p. Ac induction linear induction open closed loop polynoid open loop, low duty cycle b stage type preferred. Dynamic performances of tubular linear induction motor for. Example images of some of the various topologies are shown below. In this paper, the study uses a finite element solver with the commercial software magnet from infolytica cooperation. The induction motor is made up of the stator, or stationary windings, and the rotor. A sensorless tubular linear motor was constructed and driven by three di. Tubular linear induction motor analysis by using finite. Rotor shape influence on tubular induction actuator force.
It has a patented structure with smooth brake which prevent sliding down. Pdf design criteria of tubular linear induction motors. For low speed applications both flat and tubular linear induction motors tlim are suitable. A slim of specified parameters is designed using a userinteractive matlab program, and then compared to a similar tubular linear induction motor tlim. When the flat linear induction machine is rerolled around the motion axis, the tubular linear induction machine is obtained figure 4. Analysis and design criteria of a tubular linear induction.
Design optimization and efficiency enhancement of linear. Thrust characteristics of conventional tubular lim and fclim are compared using the equivalent circuit parameters. Tripodi department of energy and system engineering, university of pisa, via diotisalvi 2, pisa 56126, italy abstractin this paper, some design criteria for a tubular linear induction motor tlim as a fast actuator are considered. But producing goods and services is strongly related to the. The first patent in linear induction motors was obtained by the mayor of pittsburg in 1895. Baldor linear motors and stages steven engineering. Pdf tubular linear induction motor analysis by using finite. Vincenzo di dio1, giovanni cipriani1, rosario miceli1, and renato rizzo2. The overall area available for the linear induction motor drive is an important characteristic, as this determines the size and possible output power of motors that will fit within the system. Active magnetic bearing applied to a tubular linear. For example, a permanent magnet dc linear motor is similar to a permanent magnet dc rotary motor and an ac induction linear motor is similar to a squirrel cage induction motor.
This is the small model of linear tubular induction motor. A general framework for the analysis and design of tubular linear permanent magnet machines pdf. A tubular linear motor is a type of linear electric motor with a forcer consisting of a series of. The rotating machinery, magnetic physics interface available in the acdc module is used to model rotating machines such as motors or generators. Parametric performance evaluation of the designed 1meter diameter pcptlim system yields encouraging results for practical implementation. Calculating linear motor requirements baldor motion. Model of tubular lim for deriving approximate equation of thrust force. Linear induction machines resemble the principle and the topologies of rotary induction machines by the cutting and unrolling principle to obtain flat linear induction machines figure 3 2. The singlesided linear induction motor is by far the.
Pdf tubular linear induction motor analysis by using. The innovative linx cylindrical linear motor international patent pending offered by anca motion provides improved performance at lower cost when compared to conventional flat linear motors and rotary motors. Since laithwaites work on linear induction motors, many other types. Electric energy and induction motors the level of prosperity of a community is related to its capability to produce goods and services. The high speed and acceleration, standalone thermal stability and the ability to achieve high ip67 protection make linx an ideal solution for machine tools, food processing and other. Tubular linear induction motor for hydraulic capsule. Modeling linear motors or generators in comsol multiphysics. The improvement of the characteristics in tubular linear. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. Induction motors with rotor helical motion a dissertation submitted to the graduate faculty of the louisiana state university and agricultural and mechanical college.
The technology is not new but merely designed in a different form. A tubular linear primary element is constructed of a plurality of core groups, each core group being constructed of a plurality of laminated combshaped plates, each plate having a plurality of radially aligned teeth and slots. Tubular linear motors are used in applications requiring linear actuators with performance that cannot be met. Pdf design criteria of tubular linear induction motors and. Wonjong kim a design for a novel tubular highprecision directdrive brushless linear motor has been developed. In this type of motor, the stator and rotor are called primary and secondary respectively. It is well known that tubular linear induction machines have the highest force to moving mass ratio when compared with other linear motors.
Pdf in this paper a mathematical model of tubular linear induction machines tlim with hollowed induced part is recalled. Edge effect and independently supplied slot currents in. The lim operator shall consist of a control unit, one or more linear induction motors and reaction fin sections. To size a linear motor for a horizontal application you need to know. The motor is protected by the thermal effect against burning down. The finite element formulation of the field equations is discussed and the magnetic field. Design and construction of a precision tubular linear motor and controller.
Design and optimization of tubular linear permanent magnet generator with. Design optimization and control strategies for pm multiphase. Analysis and design criteria of a tubular linear induction motor for a possible use in the electromagnetic aircraft launch system abstract. A maximum weights of moving load b length of move and overall travel. Abstractin this paper, a doublesided stator tubular linear induction machine is. A cylindrical tubular armature 23 can move within the tubular indoctor 24, guided by any suitable means, for instance means with air cushions, the tubular armature 28 may constitute, the frame of a vehicle moving along the path defined by the tubular rail 24. Tubular linear motors consist of a thrust rod or tube with permanent magnets and a stator sometimes referred to as a forcer with coils. 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. The fem model is used to analyze a specific tlim design at standstill for a given supply current.
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. Design criteria of tubular linear induction motors and. The core groups are coupled together radially about an axis with the slots of the core groups facing each other toward the axis. A study on technical feasibility of applying tubular linear induction. Antonino musolino, rocco rizzo, and ernesto tripodi. Sizes vary from fractional horsepower to several thousand horsepower used for such appli. The first electromagnetic gun was undoubtedly birkelands cannon of 1918, again a reluctance device, but possibly the first tubular motor using a row of simple coils energized in sequence with dc. Tubular noncommutated dc linear motor what is a linear motor. Tubular motors can then be realised by rolling the flat linear motor around the length of travel. In this paper, we study one kind of tubular linear induction motor which has the primary configuration composed of four pieces of flattype core. These include curved motors, faceplate type drives and tubular motors.
Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. 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. In this paper, we show a new winding method that improves the efficiency of the primary core, energy density and flux modulation as well as space harmonic distribution in low speed lim. Though some losses are occurred in the plate, the overall ef. The governing equations of cfm model can be reduced to the ordinary differential equations that can be solved by numerical method and it is easy to program. Abstract tubular linear induction motor tlim can be used as a capsule pump in a large pneumatic capsule pipeline pcp system. The tubular motor manufactured by us is available in a compact design but it provides a large torque and running without noise. Finite element methods applied to the tubular linear. Design and optimization of tubular linear permanent magnet.
But tubular, or shafttype, linear motors have a construction principle that provides higher efficiency and makes them especially wellsuited for gantry applications. A tubular linear motor is a type of linear electric motor with a forcer consisting of a series of solenoids wrapped around a cylinder enclosing a movable rod that contains a number of strong cylindrical permanent magnets aligned in alternating and opposing directions. How an induction motor works by equations and physics introduction. Force engineering ltd linear induction motor options. Design of a single sided linear induction motor slim. The position of the forcer, the electrical current and the potential di. Instead of producing rotary torque from a cylindrical machine it produces linear force from a flat one. Recently, more and more attentions are focused on linear motors due to their characteristics that they can directly transform electricity energy into linear motion, among them tubular linear motors are widely used as launchers for spaceuse, and used in industry robots. The motor studied is composed of four coils, three non magnetic separations between the coils and a mover. The primary comprises a threephase winding and the secondary is a simple steel cylinder. Traditional mechanical punching machines are mainly driven by rotary motors and a complete set of intermediate transformation mechanism is needed, which results in a reduction of the system efficiency. The linear tubular motor can also be regarded as a propulsion system. Development and analysis of two alternative tubular linear motors. The application of linear induction motors to conveyors, proceedings of the iee part a.
In this paper a double stator tubular linear induction machine is presented and its performance are discussed for a possible use as a catapult in the electromagnetic acceleration of aircrafts. He tubular induction motors are used as long course actuators. Design optimization and control strategies for pm multiphase tubular linear actuators page symmetry of the machine. A linear induction motor lim is a specific type of alternating current ac, multiplephase machine that provides force and movement in a linear direction. The design equations of the slim and the equivalent circuit model are studied and discussed in detail. Baldor linear motors and stages are used in thousands. Design of singlesided linear induction motor science publishing. In this blog post, we will explore how to customize the linear. The aim of this work is to present a mathematical model for the linear induction motor. The linear induction motor lim is structurally divided into the flat and the tubular type. A parallel history of linear induction motors with applications in linear.