The pulsed linear induction motor concept for highspeed trains b. 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. Analysis, design and control aspects of linear machines. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects, whereas a conventional induction motor is arranged. Analytical equations and finite element methods fem are used. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. 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. Park korea railroad research institute, uiwang, korea1. This work addresses the design of a speed control scheme based on total slidingmode control tsmc theory for a. It is possible to combine the advantages of matrix. A linear induction motor provides linear force and motion rather than rotational torque. Speed control of fstp inverter fed induction motor drive with. 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.
However, induction motors do not inherently have the capability of variable speed of operation. Numerous applications of lims can be found in industry today, one of the most interesting being high speed magnetic levitation railway systems. Main applications of these machines are in highspeed ground transportation. 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. 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. But the recent developments in speed control methods of the asynchronous motor have led. 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. Moreover when it comes to speed, accuracy and efficiency. 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.
Abstract direct torque control is considered one of theas most efficient techniques for speed andor position tracking control of induction motor drives. Electric motor electric motor linear induction motors. This means that there is no need for slip rings and brushes. For singlesided assemblies, the reaction plate consists of 18in. Hybrid models combine the benefits of the magnetic equivalent circuit mec method 12. Speed control of induction motor 7 ways to control. A linear induction motor lim is a specific type of alternating current ac, multiplephase machine that provides force and movement in a linear direction. Induction motor seminar ppt, pdf report study mafia. Speed control of linear induction motor with thrust and stator flux. Figure 3 short primary double sided linear induction motor. For a slip of s, the speed of the secondary in a linear motor is given by. This makes constant vf the most common speed control of an induction motor. Dongguk university, seoul, korea2 abstract there have been many researches to develop linear induction motors for railway systems for last. First, the indirect fieldoriented control lim is derived, considering the end effects.
Control inputs will include the presence of hills, curves, merge areas, and other traffic ahead or behind. The change in speed or slip required is normally small. Pdf robust adaptive control of linear induction motors with. I would just like to add some practical applications of lim. Various induction motor speed control methods advantages. This slip must be present, even when operating in a fieldoriented control regime. 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. Pdf fuzzy logic control of linear induction motor emre ozkop. Request pdf speed control of linear induction motor with thrust and stator flux ripple. Nov 11, 2011 the linear induction motor is designed for high speed operation.
Linear induction motors can be manufactured in a wide range of force outputs, speeds, and footprints. The advent of vector control techniques has solved induction motor control problems. For the same reason as in the case of an induction motor, the secondary or runner cannot catch the speed of the magnetic field. By using variable frequency control, it is possible to adjust the speed of the motor either above or below base speed. Thrust control of traction linear induction motors in switch. The induction motor is therefore a machine of substantially constant speed. Induction motor equations engn1931f spring 2017 2 let. Motorola 3phase ac induction motor vector control 5 figure 32. Speed control of fstp inverter fed induction motor drive. A typical frequency converter with a special induction motor series are shown on figure 1. Introduction linear electric motors lems belong to the group of special electrical machines. The achieving of variable speed of an induction motor drive is a challenging task because of non linear behavior of the motor speed. 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.
This is used for non linear control system because of its ability of modeling a non. Sensorless field oriented control of 3phase induction motors. For a 4 pole, 50 hz induction motor, the variation in speed from noload to full load could be 1485 to 1455 rpm. Speed control of three phase induction motor electrical4u. 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. In this leaflet the following information can be found. The performance abilities of the motor will be tested in the department of electrical and computer. 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. A properly designed variable frequency inductionmotor drive can be very flexible.
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. Actual speed of an induction motor is given as n ns 1 s. The achieving of variable speed of an induction motor drive is a challenging task because of nonlinear behavior of the motor speed. Modeling of linear induction machines for analysis and control institution.
The current equations of the induction motor have a particular structure, which allows them to be written on a complex form. In this type of motor, the stator and rotor are called primary and secondary respectively. High speeds, the maximum speed of a linear motor is limited only by the bus voltage and the speed of the control electronics. The proposed solution for the normal force issue consists of a linear induction motor lim optimized for urban sml vehicles. 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. 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. Efficiency of the lim under varying air gap size and motor speed. An843, speed control of 3phase induction motor using. Thrust control of traction linear induction motors in. 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 three phase induction motor is basically a constant speed motor. Department of control and instrumentation, faculty. 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. Free download induction motor seminar ppt, pdf report. Multiple simultaneous specifications control highspeed ac. 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. The objective of this work is to control the position of a field oriented induction motor for a given reference input signal. This method is applicable to squirrel cage induction motor only. In general, the induction motor is cheaper and easier to maintain compared to other alternatives.
The following equations are important in determining the power from the panel 8. 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. In order to overcome this, a new method was developed is known as artificial neural network. 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. Jan 09, 2017 this method is applicable to squirrel cage induction motor only. We must observe care a choice of linear k induction motor lim control. 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. 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. A properly designed variable frequency induction motor drive can be very flexible. 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. Torquespeed characteristics of a 3oim with constant vf ratio. Barwell, application of linear induc tion motors to highspeed transport systems, proc. By varying the frequency, the speed of the motor can be varied. The induction motor is made up of the stator, or stationary windings, and the rotor.
Simulation results have shown the algorithm had good performances. A linear induction motor lim is an alternating current ac, asynchronous linear motor that. 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. This master thesis is completed at electrical machines and motion control, abb. The team is proposing to control the speed of the simulated linear track under magnetic levitation conditions. Speed control of vector controlled induction motors using. Main applications of these machines are in highspeed ground transportation, sliding doors, flexible manufacturing systems, robotic systems, etc.
Ceitec central european institute of technology, brno university of technology, purkynova 123, brno, czech republic email. This paper present the speed control of single phase induction motor using arduino with the controlling objectives pwm and spwm. This slip power loss can be recovered and supplied back to improve the overall. Index termslinear induction motor, equivalent circuit parameters, finite element method, vector control, material of reaction plate i. Chapter 3 induction motor and different speed control methods page no 3. L r s and be the angular velocities of the magnetic field line frequency, rotor, and slip respectively. Pdf this paper proposes a novel robust adaptive speed position tracking. Speed control of induction motor using pushpull converter and three phase svpwm inverter dr. Power electronics and motion control conference ipemcecce. The result is a flat stator, or upper section, of iron laminations. The torque developed in this method is proportional to the square of the supply voltage. Optimalairgap control of a linear induction motor for korean railway transit 1h. Speed tracking of a linear induction motorenumerative nonlinear model predictive control jean thomas and anders hansson linkoping university post print n. Abstract today induction motor requires a variable speed control to serve wide range of applications.
Asynchronous motors are the most widely used electrical motors due to their reliability, low cost, ruggedness and robustness. How an induction motor works by equations and physics. Vivek brahmbhatt already has explained very nicely the construction of lim. Sensorless speed non linear control of induction motor. Performance analysis of the linear induction motor for the deepunderground highspeed gtx 202 maximum speed should be around 34.
S l r the flux in the singleturn coil on the rotor surface is. The linear force is given by the equation shown below. Characteristics of linear induction motor considering. Hence, a dcdc pushpull converter merge with dcac three phase inverter, it is possible. The pulsed linear induction motor university of edinburgh.
The speed of induction motor can be varied by changing supply voltage. The speed control of induction motor is done at the cost of decrease in efficiency and low electrical power factor. These effects combine to produce a poor power factor and. Exp erimen tal system used to test the pulsed linear induction launc her concept. Most linear motors are used in the machine construction industry and for production automation purposes. Therefore the efficiency of three phase induction motor is reduced by this method of speed control. Normally lim is used to make a motion frictionless absolutely. However, asynchronous motors do not inherently have the capability of variable speed operation. However,that constitutes a theoretical challenge, knowing that the model of the induction motor is. Sliding mode speed regulation of linear induction motors based on direct thrust control with. 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. Performance analysis of the linear induction motor for the. Force engineering ltd linear induction motor control. Hence, the synchronous speed changes with change in supply frequency.
Therefore, by varying the voltage and frequency by the same ratio, flux and hence, the torque can be kept constant throughout the speed range. Speed control of induction motor 7 ways to control induction. Induction and synchronous machines differ in the way secondary is excited. Where s is the slip of the linear induction motor and is given as. However, this control scheme has several drawbacks. This project examines the use of linear induction motors lims as the primary propulsion. Mec design and construction of a pulsed linear induction motor. Linear parameter varying control of induction motors. 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. Sensorless field oriented control of 3phase induction. Speed tracking of a linear induction motorenumerative. The thrust velocity curve of the linear induction motor is similar to that of the speed torque curve of the rotary induction motor. A three phase induction motor is basically a constant speed motor so its somewhat difficult to control its speed.
Constant cooling by integrated forced ventilation independent of motor speed provides high continuous torque capability at low speed in servodrive applications machine tools. They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required. With an aim of reducing the cost of the control for the induction motor, several algorithms of estimate of rotor. Linear induction motors canbe considered as the rotary induction motor sectioned axially and. The pulsed linear induction motor concept for high speed trains b. It is widely used in industry due to low cost and rugged construction. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. They are available in a wide range of power ratings. This is used for nonlinear control system because of its ability of modeling a non. 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. Induction motors are widely used electrical motors due to their reliability, low cost and robustness. Pdf construction of three phase linear induction motor. Linear induction motor motion control h2w technologies. The value of s for a medium sized motor may vary from 1 on no load to 3% on full load.
The linear induction motor is designed for high speed operation. An innovative workbench for dynamic tests was developed to measure the parameters of interest. It can control the speed of an induction motor over a range from as little as. Control of induction motors by using programmable logic. Introduction linear induction motor has been applied in urban transportation system widely, mainly because of its low. Linear induction machines featuring secondary conductive coating pdf. 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. Furthermore, the constant thrust control in switch areas is analyzed and the future research work is discussed. In 2, an equivalentcircuit model for a highspeed industrial transportation. Vehicle propulsion using continuous track linear induction motors. Figure 3 shows the relation between the voltage and. Main applications of these machines are in high speed ground transportation, sliding doors, flexible manufacturing systems, robotic systems, etc.
What is a linear induction motor and how does it work. Jun 30, 2015 a three phase induction motor is basically a constant speed motor. This paper presents a field oriented control scheme of the linear induction motor lim in order to achieve high performance of the machine. 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. Due to this reason, earlier dc motors were applied in most of the electrical drives. The rotor in an induction motor is not externally excited. B when citing this work, cite the original article. 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. Typical speeds for linear motors are 3 meters per second with 1 micron resolution and over 5 meters per second, 200ips, with coarser resolution. Linear electric motors lems belong to the group of special electrical machines. Linear motors complement todays linear motion technologies. The most commonly used controller for the speed control of. Optimalairgap control of a linear induction motor for. An843, speed control of 3phase induction motor using pic18 mcus.
1047 1480 366 824 1221 153 1181 235 856 623 565 1459 213 756 1309 298 564 154 1012 1615 377 1422 947 1142 307 656 1250 1603 170 607 364 826 856 211 1278 675 841 829 101 1060 1323 826