We must observe care a choice of linear k induction motor lim control. Typical speeds for linear motors are 3 meters per second with 1 micron resolution and over 5 meters per second, 200ips, with coarser resolution. It is widely used in industry due to low cost and rugged construction. An843, speed control of 3phase induction motor using. In order to overcome this, a new method was developed is known as artificial neural network. However, induction motors do not inherently have the capability of variable speed of operation. This is used for nonlinear control system because of its ability of modeling a non. The proposed solution for the normal force issue consists of a linear induction motor lim optimized for urban sml vehicles. But the recent developments in speed control methods of the asynchronous motor have led.
Exp erimen tal system used to test the pulsed linear induction launc her concept. Torquespeed characteristics of a 3oim with constant vf ratio. Speed control of linear induction motor with thrust and stator flux. Actual speed of an induction motor is given as n ns 1 s. Multiple simultaneous specifications control highspeed ac. The pulsed linear induction motor concept for highspeed trains b. The value of s for a medium sized motor may vary from 1 on no load to 3% on full load. These effects combine to produce a poor power factor and. Due to this reason, earlier dc motors were applied in most of the electrical drives. Figure 3 shows the relation between the voltage and. For the same reason as in the case of an induction motor, the secondary or runner cannot catch the speed of the magnetic field. Power is nothing without control and whether it is for a roller coaster, a public transportation system or an industrial use, projects that require linear motion often have diverse and in many cases complex control requirements.
Nov 11, 2011 the linear induction motor is designed for high speed operation. The torque developed in this method is proportional to the square of the supply voltage. First, the indirect fieldoriented control lim is derived, considering the end effects. This method is applicable to squirrel cage induction motor only. 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. Abstract direct torque control is considered one of theas most efficient techniques for speed andor position tracking control of induction motor drives.
The advent of vector control techniques has solved induction motor control problems. Speed tracking of a linear induction motorenumerative. Moreover when it comes to speed, accuracy and efficiency. In this type of motor, the stator and rotor are called primary and secondary respectively. Jan 09, 2017 this method is applicable to squirrel cage induction motor only. An843, speed control of 3phase induction motor using pic18 mcus. However,that constitutes a theoretical challenge, knowing that the model of the induction motor is. Free download induction motor seminar ppt, pdf report. Pdf fuzzy logic control of linear induction motor emre ozkop.
Force engineering ltd linear induction motor control. 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. Also the implementation of a hardware and software for speed control and protection with the result obtained from the test on induction motor performance is provided and this idea presents a design and implementation of a monitoring and control system for the three phase induction motor based on programmable logic controller plc. Department of control and instrumentation, faculty. Jun 30, 2015 a three phase induction motor is basically a constant speed motor. Linear motors complement todays linear motion technologies. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. Induction and synchronous machines differ in the way secondary is excited. Speed control of induction motor 7 ways to control.
Pdf construction of three phase linear induction motor. Induction motors are widely used electrical motors due to their reliability, low cost and robustness. Soft starters are used for induction motor drives having fan, pump and blowers types load where load torque is directly proportional to square of speed. Closed loop vf speed control method the basis of constant vf speed control of induction motor is to apply a variable magnitude and variable frequency voltage to the motor. This slip power loss can be recovered and supplied back to improve the overall. For a 4 pole, 50 hz induction motor, the variation in speed from noload to full load could be 1485 to 1455 rpm. Thrust control of traction linear induction motors in. By varying the frequency, the speed of the motor can be varied. 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. For a slip of s, the speed of the secondary in a linear motor is given by. In 2, an equivalentcircuit model for a highspeed industrial transportation. The linear force is given by the equation shown below. Modeling of linear induction machines for analysis and control institution. They are available in a wide range of power ratings.
It can control the speed of an induction motor over a range from as little as. Before discussing the methods to control the speed of three phase induction motor one should know the basic formulas of speed and torque of three phase. 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. A linear induction motor lim is an alternating current ac, asynchronous linear motor that. The team is proposing to control the speed of the simulated linear track under magnetic levitation conditions.
Figure 3 short primary double sided linear induction motor. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. Photo courtesy of control techniques the main power circuit consists of a sixthyristor bridge circuit as discussed in chapter 2, which rectifies the incoming a. This paper present the speed control of single phase induction motor using arduino with the controlling objectives pwm and spwm. Barwell, application of linear induc tion motors to highspeed transport systems, proc. This means that there is no need for slip rings and brushes. A properly designed variable frequency induction motor drive can be very flexible. Introduction linear induction motor has been applied in urban transportation system widely, mainly because of its low. This paper presents a field oriented control scheme of the linear induction motor lim in order to achieve high performance of the machine. The result is a flat stator, or upper section, of iron laminations. It can control the speed of an induction motor over a range from as little as 5% of base speed up to about twice base speed. Speed control of induction motor 7 ways to control induction. Most linear motors are used in the machine construction industry and for production automation purposes. Linear parameter varying control of induction motors.
Where s is the slip of the linear induction motor and is given as. Introduction linear electric motors lems belong to the group of special electrical machines. Dongguk university, seoul, korea2 abstract there have been many researches to develop linear induction motors for railway systems for last. They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required. Chapter 3 induction motor and different speed control methods page no 3. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects.
L r s and be the angular velocities of the magnetic field line frequency, rotor, and slip respectively. In a linear induction motor lim, the primary inverter is directly controlled by the inverter switching winding corresponds to the stator winding of a rotary states selected using switching table. 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. The speed control of induction motor is done at the cost of decrease in efficiency and low electrical power factor. Characteristics of linear induction motor considering. Main applications of these machines are in highspeed ground transportation. Abstract today induction motor requires a variable speed control to serve wide range of applications. Index termslinear induction motor, equivalent circuit parameters, finite element method, vector control, material of reaction plate i. A properly designed variable frequency inductionmotor drive can be very flexible. This makes constant vf the most common speed control of an induction motor. Power electronics and motion control conference ipemcecce. The objective of this work is to control the position of a field oriented induction motor for a given reference input signal. Performance analysis of the linear induction motor for the.
A three phase induction motor is basically a constant speed motor so its somewhat difficult to control its speed. The achieving of variable speed of an induction motor drive is a challenging task because of non linear behavior of the motor speed. Analytical equations and finite element methods fem are used. Efficiency of the lim under varying air gap size and motor speed. Performance analysis of the linear induction motor for the deepunderground highspeed gtx 202 maximum speed should be around 34. Linear induction motors can be manufactured in a wide range of force outputs, speeds, and footprints. The induction motor is made up of the stator, or stationary windings, and the rotor. However, this control scheme has several drawbacks. Motorola 3phase ac induction motor vector control 5 figure 32. A linear induction motor provides linear force and motion rather than rotational torque. Constant cooling by integrated forced ventilation independent of motor speed provides high continuous torque capability at low speed in servodrive applications machine tools. Furthermore, the constant thrust control in switch areas is analyzed and the future research work is discussed.
Speed control of three phase induction motor electrical4u. The speed of induction motor can be varied by changing supply voltage. Request pdf speed control of linear induction motor with thrust and stator flux ripple. Speed control of induction motor using pushpull converter and three phase svpwm inverter dr.
B when citing this work, cite the original article. It is possible to combine the advantages of matrix. Park korea railroad research institute, uiwang, korea1. 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. Optimalairgap control of a linear induction motor for korean railway transit 1h.
Electric motor electric motor linear induction motors. 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. Linear induction machines featuring secondary conductive coating pdf. Main applications of these machines are in highspeed ground transportation, sliding doors, flexible manufacturing systems, robotic systems, etc. The pulsed linear induction motor university of edinburgh. Pdf robust adaptive control of linear induction motors with. The current equations of the induction motor have a particular structure, which allows them to be written on a complex form.
In this leaflet the following information can be found. Vehicle propulsion using continuous track linear induction motors. Induction motor seminar ppt, pdf report study mafia. How an induction motor works by equations and physics. Ac induction motor speedtorque characteristic squirrelcage ac induction motors are popular for their simple construction, low cost per horsepower and low maintenance they contain no brushes, as do dc motors. What is a linear induction motor and how does it work. Ac induction motor speed torque characteristic squirrelcage ac induction motors are popular for their simple construction, low cost per horsepower and low maintenance they contain no brushes, as do dc motors. The thrust velocity curve of the linear induction motor is similar to that of the speed torque curve of the rotary induction motor. For singlesided assemblies, the reaction plate consists of 18in.
Linear induction motors canbe considered as the rotary induction motor sectioned axially and. Sensorless field oriented control of 3phase induction. Speed control of fstp inverter fed induction motor drive. Pdf this paper proposes a novel robust adaptive speed position tracking. Vivek brahmbhatt already has explained very nicely the construction of lim.
By using variable frequency control, it is possible to adjust the speed of the motor either above or below base speed. Sliding mode speed regulation of linear induction motors based on direct thrust control with. Speed control of fstp inverter fed induction motor drive with. Normally lim is used to make a motion frictionless absolutely.
The change in speed or slip required is normally small. The shape and operation of a linear induction motor can be visualized as depicted in the figure by making a radial cut in a rotating induction machine and flattening it out. The most commonly used controller for the speed control of. However, asynchronous motors do not inherently have the capability of variable speed operation. This master thesis is completed at electrical machines and motion control, abb. Hence, the synchronous speed changes with change in supply frequency. The following equations are important in determining the power from the panel 8. The small blower motor is an induction machine that runs continuously, thereby allowing the main motor to maintain full torque at low speed without overheating. Control of induction motors by using programmable logic. Dec 17, 2019 when the speed control of three phase induction motor is done by adding resistance in rotor circuit, some part of power called, the slip power is lost as i 2 r losses. Asynchronous motors are the most widely used electrical motors due to their reliability, low cost, ruggedness and robustness. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Hence, a dcdc pushpull converter merge with dcac three phase inverter, it is possible. 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.
This work addresses the design of a speed control scheme based on total slidingmode control tsmc theory for a. Linear electric motors lems belong to the group of special electrical machines. Optimalairgap control of a linear induction motor for. The achieving of variable speed of an induction motor drive is a challenging task because of nonlinear behavior of the motor speed.
Main applications of these machines are in high speed ground transportation, sliding doors, flexible manufacturing systems, robotic systems, etc. A linear induction motor lim is a specific type of alternating current ac, multiplephase machine that provides force and movement in a linear direction. This is used for non linear control system because of its ability of modeling a non. Mec design and construction of a pulsed linear induction motor.
Numerous applications of lims can be found in industry today, one of the most interesting being high speed magnetic levitation railway systems. Thrust control of traction linear induction motors in switch. Analysis, design and control aspects of linear machines. High speeds, the maximum speed of a linear motor is limited only by the bus voltage and the speed of the control electronics. Sensorless speed non linear control of induction motor. Therefore, by varying the voltage and frequency by the same ratio, flux and hence, the torque can be kept constant throughout the speed range. The performance abilities of the motor will be tested in the department of electrical and computer. Sensorless field oriented control of 3phase induction motors. This slip must be present, even when operating in a fieldoriented control regime. Various induction motor speed control methods advantages.
Therefore the efficiency of three phase induction motor is reduced by this method of speed control. S l r the flux in the singleturn coil on the rotor surface is. This project examines the use of linear induction motors lims as the primary propulsion. Zimmerman pulsed power sciences center sandia national laboratories, albuquerque, nm 87 185 abstract the seraphim segmented rail phased induction motor concept is a linear induction. With an aim of reducing the cost of the control for the induction motor, several algorithms of estimate of rotor. The linear induction motor is designed for high speed operation. Simulation results have shown the algorithm had good performances. A typical frequency converter with a special induction motor series are shown on figure 1. Linear induction motor motion control h2w technologies. Hybrid models combine the benefits of the magnetic equivalent circuit mec method 12. A three phase induction motor is basically a constant speed motor. 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. 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. An innovative workbench for dynamic tests was developed to measure the parameters of interest.
Abstract control of induction motor im is well known to be difficult owing to the fact the mathematical models of im are highly nonlinear and time variant. Where f s is the supply frequency in hz, v s is the velocity of the linear traveling field in meter per second, and t is the linear pole pitch i. The rotor in an induction motor is not externally excited. Synchronous speed of the rotating magnetic field of an induction motor is given by, where, f frequency of the supply and p number of stator poles. The pulsed linear induction motor concept for high speed trains b. Ceitec central european institute of technology, brno university of technology, purkynova 123, brno, czech republic email. Induction motor equations engn1931f spring 2017 2 let. Speed control of vector controlled induction motors using. Linear motors lm enable linear movements at high speeds with great accuracy. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects, whereas a conventional induction motor is arranged. Control inputs will include the presence of hills, curves, merge areas, and other traffic ahead or behind. Speed tracking of a linear induction motorenumerative nonlinear model predictive control jean thomas and anders hansson linkoping university post print n. I would just like to add some practical applications of lim. The induction motor is therefore a machine of substantially constant speed.