End effects and other geometry subtleties of a linear motor make it unique, and a means of optimizing efficiency with both the motor geometry and the motor control scheme will be analyzed to create a highspeed linear induction motor lim with a higher efficiency than what is possible with conventional motors and controls. 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. The speed control of induction motor is done at the cost of decrease in efficiency and low electrical power factor. The application serves as an example of ac induction vector control drive design using a motorola dsp with sdk support. 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. 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. 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. Robust controller is designed using hybrid currentflux dq equations of an induction machine. Scalar control is the term used to describe a simpler form of motor control, using nonvectorcontrolled drive schemes. Linear electric motors lems belong to the group of special electrical machines. Nov 11, 2011 the linear induction motor is designed for high speed operation. The linear induction motor is designed for high speed operation. As induction motors are widely being used, their speed control may be required in many applications.
Department of control and instrumentation, faculty. A linear induction motor provides linear force and motion rather than rotational torque. Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects, whereas a conventional induction motor is arranged. The speed torque curve of a squirrel cage induction motor and the soft starter, 2892016 duration. This slip power loss can be recovered and supplied back to improve the overall. Steady state response of speed, current and torque in induction motor are also obtained using this scheme. The linear induction motor science publishing group. The rotor will constantly be turning to align its magnetic field with that of the stator field. Pdf programmable logic control based simultaneous speed.
Methods of speed control of induction motor electrical concepts. Oct 10, 1972 the invention relates to a speed control system for a linear induction motor. Fellah abstract in the present paper, the mover speed control of a linear induction motor lim using a. In a traditional electric motor, the rotor rotating part spins inside the stator static part in a linear motor, the stator is unwrapped and laid out flat and the rotor moves. 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. Induction motor runs through direct ac line the amount of power given to it decides to what rpm it does rotates. We will now employ these models within simulink to simulate the system response and design different approaches to control. These files are taken from the 2018 2019 oriental motor u. In the rotary induction motor, the speed of the secondary in the linear induction motor is less than the synchronous speed v s and is given as.
Speed control of linear induction motor using sliding mode controller considering the end effects a. Speed control of linear induction motor considering endeffects. An induction motor uses an alternating current in a stator, or stationary winding, to induce a magnetic field in a metal cage or wire winding as the rotor. Main applications of these machines are in highspeed ground transportation, sliding doors, flexible manufacturing systems, robotic systems, etc. Controlling 3 phase ac induction motors using the pic18f4431. Induction motor speed control project serves this purpose of controlling the speed of the induction motor.
Speed control of three phase induction motor electrical4u. Read more methods of speed control of induction motor. Speed of a dc shunt motor can be varied very easily with good efficiency, but in case of induction motors, speed reduction is accompanied by a corresponding loss of efficiency and poor power factor. High speed linear induction motor efficiency optimization.
Induction motors have been traditionally used as constant speed motors supplied by the ac power source. Performance analysis of the linear induction motor for the. Before discussing the methods to control the speed of three phase induction motor one should know the necessary formulas of speed. Force engineering ltd linear induction motor control. Pdf speed control of linear induction motor using sliding mode. The bxii series brushless dc motor and driver packages offer high performance and high function, up to 4,000 rmin, for a wide range of applications. Variable voltage variable frequency speed control of. The performance of the proposed dtfc method is analyzed with considering endeffect.
Linear motors are electric induction motors that produce motion in a straight line rather than rotational motion. The interaction of the electric and magnetic fields drives the motor without any connections between the moving parts via a slip ring, making it highly reliable. 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. Controlling 3 phase ac induction motors using the pic18f4431 pdf this application note describes how the pic18f4431 may be used to control an acim using open and closedloop vf control strategies. End effects and other geometry subtleties of a linear motor make it unique, and a means of optimizing efficiency with both the motor geometry and the motor control scheme will be analyzed to create a high speed linear induction motor lim with a higher efficiency than what is possible with conventional motors and controls. First of all mentions linear induction machines in 1890, only two years after the discovery of. Jun 05, 2018 out of all the electrical machines, induction motor is the most used machine in industries. 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. Methods of speed control of induction motor electrical.
The pulsed linear induction motor concept for highspeed trains b. The speed control of induction motor is done at the price of reduce in efficiency and low power factor. They are capable of speeds up to 1800 insec 45 ms and are typically used in applications where accurate positioning is not required. The speed control method of our inverter units is divided into the two types. Speed control of vector controlled induction motors using. Linear induction motor motion control h2w technologies.
The voltage signal a is low when the speed detected value to the speed. In this paper, the mover speed control of a linear induction motor considering the endeffects compensation is proposed. By using pwm strategies, in the reference 45 inverter is used to drive the speed of induction motor, ac choppers are used in the reference67 for the speed control of induction motor. The speed set value d and the detected voltage e of the speed generated by a tachogenerator is compared in the comparison amplifier block. Ac induction motor speed control so what can we do to control the speed of an ac induction motor. Electric motor electric motor linear induction motors. The pulsed linear induction motor university of edinburgh. We can modulate the power of the ac line to vary the speed of the induction motor through ac driver circuitry.
If the motor slip is known, the rotor speed can be expressed by the equation. Jean thomas and anders hansson, speed tracking of a linear induction motor enumerative. The result is a flat stator, or upper section, of iron laminations. The speed of induction motor can be varied by changing supply voltage. The files listed below are available for you to download in pdf format. 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. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Then for the main motor, synchronous speed is 120f 1. Ceitec central european institute of technology, brno university of technology, purkynova 123, brno, czech republic email.
Nonlinear model predictive control, 20, ieee transactions on. In the reference 3 different types of pwm strategies have been used for speed control of induction motor drive. However, recently, it has been increasingly used as variable speed motors driven by an inverter. Speed tracking of a linear induction motorenumerative. 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. In this type of motor, the stator and rotor are called primary and secondary respectively. Product catalog, except where noted with an asterisk. This induces an electric field in a coil or squirrel cage to drive a rotor. The book principles of electrical machines book by vk mehta and rohit mehta is an ideal text for students who look to gain a current and clear understanding of the subject as all theories and concepts are explained with lucidity and clarity. The most commonly used controller for the speed control of. The 3phase set of currents, each of equal magnitude and with a phase. A three phase induction motor is mostly a constant speed motor so its fairly not easy to control its speed. The rotor speed of an induction motor is given by the equation shown below.
Pdf speed tracking of a linear induction motor enumerative. The linear force is given by the equation shown below. Speed control of a three phase induction motor using pwm. Succinctly divided in 14 chapters, the book delves into important concepts of the subject which include armature reaction and commutation. Dec 23, 2017 the speed control of induction motor by considering to control on rotor side can subdivide into several speed controlling methods such as. The driver is user friendly with easy wiring, data setting and led display on the front panel and is compact and easy to mount. Jean thomas and anders hansson, speed tracking of a linear induction motorenumerative. The torque developed in this method is proportional to the square of the supply voltage. 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 specific type of alternating current ac, multiplephase machine that provides force and movement in a linear direction. Jun 30, 2015 a three phase induction motor is basically a constant speed motor. This paper introduces a speed control of linear induction motor lim by using three different strategies of control. Application of the linear induction motor to highspeed. Simulink modeling page we generated two different dc motor models in simulink.
Speed control of single phase induction motor using ac. The page also covers the construction and working principle of the linear induction motor along with the derivation of expression of speed. Speed control of linear induction motor using sliding mode. Induction motor seminar ppt, pdf report study mafia. Products marked with an asterisk have been introduced since the product catalog was released and are therefore not included in the printed. Numerous applications of lims can be found in industry today, one of the most interesting being high speed magnetic levitation railway systems. More than 90% of motors used in industries are squirrel cage induction motor due to its rugged and maintenance free design. A three phase induction motor is basically a constant speed motor so its somewhat difficult to control its speed. Pdf speed control of linear induction motor using sliding. The invention relates to a speed control system for a linear induction motor. The speed control of induction motor by considering to control on rotor side can subdivide into several speed controlling methods such as.
Free download induction motor seminar ppt, pdf report. The analysis has been done in terms of thd in their line current. Rotor speed is taken out from these equations and it is used as a scheduling variable. Adding an external resistant into rotor side circuit. It is widely used in industry due to low cost and rugged construction. A 3phase induction motor uses current delivered in three phases in a sequence into the coils of a stator to create a rotating magnetic field. A three phase induction motor is basically a constant speed motor. The pulsed linear induction motor concept for high speed trains b.
Speed control methods of various types of speed control motors. Generally an induction motor operates at almost constant speed as the load is varied. Speed control of an induction motor there is a various method of speed control of an 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. 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.
May 31, 2019 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. Constant cooling by integrated forced ventilation independent of motor speed provides high continuous torque capability at low speed in servodrive applications machine tools. Speed control of linear induction motor with thrust and stator flux. A typical frequency converter with a special induction motor series are shown on figure 1. It also illustrates the usage of dedicated motor control libraries that are included in the sdk. This method is applicable to squirrel cage induction motor only. A comparison with the traditional induction motor model is also performed. An induction motor is practically a constant speed motor, that means, for the entire loading range, change in speed of the motor is quite small.
Control tutorials for matlab and simulink motor speed. The advent of vector control techniques has solved induction motor control problems. Main applications of these machines are in highspeed ground transportation. Performance analysis of the linear induction motor for the deepunderground highspeed gtx 202 maximum speed should be around 34. Pdf principles of electrical machines book by vk mehta. Chapter 3 induction motor and different speed control methods page no 3. Citations 223 references 0 direct thrust control of a linear induction motor using a reducedswitch threelevel converter. The basic idea of an electric motor is to generate two magnetic fields. 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. The difference in speed between rotor, the synchronous speed and the rotating.
Characteristically, linear induction motors have a finite primary or secondary length, which generates endeffects. Perphase equivalent circuit of a linear induction motor lim. The control scheme as thrust, flux and current, is proposed. In this paper the speed control method of lim, which lead to optimal control characteristic of motor such as thrust, flux and current, is proposed.
Speed control of linear induction motor using sliding mode controller considering the end effects article pdf available in journal of electrical engineering and technology 71. Speed control of a three phase induction motor using. Therefore the efficiency of three phase induction motor is reduced by this method of speed control. Open loop control of induction motor im is used in this inverter scheme. Pdf direct torque control is considered as one of the most efficient techniques for speed andor position tracking control of induction motor drives find, read. Different speed control methods of induction motor are explained below. From the equation 1 it is clear that the motor speed can be changed by a change in frequency f, a number of poles p, and slip s. A linear model of the system can be extracted from the simulink model into the matlab workspace. The linear induction motor offers considerable advantage at high speeds, it is not.
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