Refer back to this diagram as the operational requirements of the singlephase motor are discussed. Perform an analysis on induction machines which is the most rugged and the most. Thus from the working principle of three phase induction motor, it may be observed that the rotor speed should not reach the synchronous speed produced by the stator. Lecture 6 three phase induction motors cairo university. The threephase induction motor is the extensively used for various kinds of industrial drives.
Concept of rotating magnetic field, operating principle, construction, classification and types singlephase, threephase, squirrelcage, slipring, doublecage types. Pwms, one less than the three required to control a 3 phase induction motor. This application note also covers the basics of induction motors and. The speed control of three phase induction motor is essential because the motor control industry is a dominant sector. These motors are selfstarting and use no capacitor, start winding, centrifugal switch or other starting device. Speed control of a three phase induction motor using pwm inverter. Applications of threephase induction motors of size varying from half a kilowatt to thousands of kilowatts are numerous. Noload and blocked rotor test on an induction machine aim theory. Nptel provides elearning through online web and video courses various streams. The rotor will constantly be turning to align its magnetic field with that of the stator field. Three phase induction motors used in explosive atmospheres w60 line squirrel. To obtain the load performance characteristics of a three phase squirrelcage induction motor. There are various methods which are used for the speed control of three phase induction motor such as stator. In this module, containing six lessons 2934, mainly, the study of induction motors, fed from balanced threephase supply, will be described.
A 3 phase induction motor can be used for different applications with various speed and load requirements. Induction motor works on the principle of electromagnetic induction. Different speed control methods of induction motor are explained below. View notes l30nkdet ee nptel from electrical ee212 at international institute of information technology. Dec 29, 2017 apr 07, 2020 ppt three phase induction motor electrical engineering ee notes edurev is made by best teachers of electrical engineering ee. Introduction to single phase induction motor nptel. In this application note, we will generate a third pwm in software, using a general purpose timer and an io pin resource that are readily available on the picmicro microcontroller. Types, construction and principle of operation, 3 phase induction motor, general phasor diagram, equivalent circuit, power and torque relations, condition for. A three phase, 12 pole, salient pole alternator is coupled to a diesel engine running at 500 rpm. Phasor diagram of induction motor on noload and loaded conditions, visualization of a threephase induction. When a motor is designed in such a way that impedance of the aluminum conductor of the rotor is. Introduction types of electrical machines types of 3ph induction motor basic principle working principle compnents of induction motor application comparision between 1ph i. Lecture series on basic electrical technology by prof. As the torque at zero rotor speed is nonzero, the induction motor is selfstarting.
Three phase induction motor drive using igbts and constant v. The single phase controller described previously can be introduced singly in each phase or line, to form a three phase controller. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. Search wegthreephaseinductionmotorsmasterline50019089brochureenglish. This document is highly rated by electrical engineering ee students and has been viewed 2456 times. These are excited by a balanced three phase voltage supply. Rotating magnetic field in threephase induction motor nptel.
A basic tutorial on computer simulation of phase controlled. It is similar to that of a three phase induction motor. It is a 16 bit highperformance digital signal controller dsc. Almost 80% of the mechanical power used by industries is provided by three phase induction motors because of its simple and rugged construction, low cost, good operating characteristics, the absence of commutator and good speed regulation. Induction machines guru nanak dev engineering college. Nov 27, 2019 thus from the working principle of three phase induction motor, it may be observed that the rotor speed should not reach the synchronous speed produced by the stator.
Characteristics of induction motors nidec corporation. Differentiate between the various types of generating electric power stations. Apr 02, 2008 lecture series on basic electrical technology by prof. If the speeds become equal, there would be no such relative speed, so no emf induced in the rotor, and no current would be flowing, and therefore no torque would be generated. Electrical engineering basic electrical technology nptel. Fall 2005 ee595s electric drive systems 3 voltsperhertz control. There exist a variety of connections for three phase ac voltage controller. The most common type of ac motor being used throughout the work today is the induction motor. Start induction motor dynamic and steadystate performance of a. Starting methods for singlephase induction motor nptel.
Further, in an induction machine, the windings are not all located in the same. Physical layout of induction motor in an induction motor induction refers the field in the rotor is induced by the stator currents and asynchronous refers that the rotor speed is not equal to the stator speed. In 1889, dolivodobrovolsky invented the induction motor with the wound. Introduction this application note describes the design of a 3phase ac induction motor drive with volts per hertz control in closedloop vhz cl. Fall 2005 ee595s electric drive systems 36 the plan continued achieving 14. Gradually apply three phase voltage across motor stator terminals via the autotransformer d. The basic idea of an electric motor is to generate two magnetic fields. Equations 1 3 represent the currents that ow in the three phase windings. Suad ibrahim shahl 26 equivalent circuit model analysis example a 480v, 60 hz, 6pole, three phase, deltaconnected induction motor has the following parameters. Single phase induction motor has cage rotor and this is main winding and this is auxiliary or starting.
It consists dc source amplitude is 500, three phase pwm inverter and three phase induction motor. General theory of induction motors nptel one, used for threephase induction motor will be presented. The three phase induction motor is the most widely used electrical motor. These are excited by a balanced threephase voltage supply. Threephase induction motor, cage and wound slipring rotor, synchronous and rotor speed, slip, induced voltages in stator winding and rotor bar. The sinusoidal stator phase currents fed in the stator coils create a magnetic field. Dc source is connected to the dc side of the converter.
As induction motors are widely being used, their speed control may be required in many applications. Constructional details of a practical single phase transformer, core, winding. All we need to do is to keep daxis stator current constant. Threephase induction motors are sometimes built with aluminum frames. A wound rotor rotating field which has the same number of poles as the. Constructional features and principle of operation. Module 8 threephase induction motor version 2 ee iit, kharagpur lesson. Find the percentage slip and number of poles of the induction motor. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. These are of two types, squirrel cage and slip ring motors. It is based on freescales 56f800e microcontrollers. Nov 04, 2012 introductionan induction motor im is a type ofasynchronous acmotor where power is supplied to therotating device bymeans ofelectromagneticinduction three phase induction motors 4.
Nov 27, 2019 the three phase induction motor is the most widely used electrical motor. Speed control of a three phase induction motor using pwm. It supplies an induction motor ich has a full load speed of 144wh 0 rpm. And if it is answers generator it will be just above 1,500 rmp we will not discuss about induction generator only little about motor right. A threephase stator similar to that of an induction motor. Synchronous motors are three phase ac motors which run at synchronous speed, synchronous motors have the following characteristics. The 3phase set of currents, each of equal magnitude and with a phase. To measure the inrush current when the motor starts.
There are two basic reasons for the use of singlephase motors rather than 3phase motors. Noload and blocked rotor test on an induction machine aim. Two digital multimeters and fluke power quality meter with banana cables from the. Some singlephase induction motors are also called squirrel cage motors because of. Introductionan induction motorim is a type ofasynchronous acmotor where power is supplied to therotating device bymeans ofelectromagneticinduction threephase induction motors 4. Be careful it can hurt to tangle with a threephase motor. Module 8 threephase induction motor version 2 ee iit, kharagpur lesson 29 rotating magnetic field in threephase induction. The three phase induction motor is the extensively used for various kinds of industrial drives. Load tests on a three phase induction motor and measurement of the inrush current objectives. Slip of a power induction motor is 2 to 3% when the motor is operated under the rated load.
Synchronous motors are threephase ac motors which run at synchronous speed, synchronous motors have the following characteristics. They have very simple and rugged almost unbreakable construction. A three phase stator similar to that of an induction motor. Induction motor 1 chapter 3 induction motor bee23 electrical machine power system 2 learning outcomes.
The above value becomes somewhat larger with small singlephase motors. Historythe induction motor with a wrapped rotor wasinvented by nikola tesla in. Moduleiv 10 hours single phase induction motor, theory of operation double revolving field theory, equivalent circuit, determination of parameters methods of starting, split phase starting, repulsion starting, shaded pole starting, performance characteristics. So next we will be you know in another example other 3 or 4 examples and with that we will close the single phase. An843, speed control of 3phase induction motor using. The singlephase induction motor is much the same in construction as the threephase motor.
Vf speed control of 3 phase induction motor using space. The above value becomes somewhat larger with small single phase motors. Disconnect any mechanical load connected to the induction motor. A successful salesman for general electrics motor division once remarked to one of your instructors that, when asked by a customer how a motor.
List and describe the more commonly used equipment in an electric substation. And generally we will find it is a 4 pole machine, but the magnetic field. Note down the machine ratings and calculate rated current of the machine noload test. Fall 2005 ee595s electric drive systems 2 overview of strategies voltsperhertz control constant slip control fieldoriented control. Pwms, one less than the three required to control a 3phase induction motor. So, now principle of induction motor right so, the operation of three phase induction. Construction of three phase induction motor electrical4u. An843, speed control of 3phase induction motor using pic18 mcus. Umanand, principal research scientist, power electronics group, cedt, iisc bangalore. View notes l29nkdet ee nptel from eso 203 at iit kanpur. To control the current and voltage of three phase loads, three phase ac voltage controller are required.
Three phase full wave controlled bridge rectifier with r load fig 32. The 3 phase set of currents, each of equal magnitude and with a phase. They are found everywhere from a small workshop to a large manufacturing industry. Starting of 3 phase induction motors, high starting torque motors, speed control, rheostatic method, pole changing method cascade control of speed, double cage induction motor, cogging and crawling of induction motor, induction generator. Now suddenly e and machine was running at 1500 rpm close to that. There are two basic reasons for the use of single phase motors rather than 3 phase motors. Umanand, principal research scientist, power electronics group, cedt, iisc bangalore for more detail. Vvvf for controlling the speed of a threephase induction motor im by using vf control strategy in open loop mode. The bars forming the conductors along the rotor axis are connected by a thick metal ring at the ends, resulting in a short circuit as shown in figure 1. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. When three phase supply is given to the stator winding, a rotating magnetic field of constant magnetic field is produced. Dc motor, the ac induction motor, and the ac synchronous motor. This would result in a balanced three phase current.
At the end of the lecture, student should be able to. Threephase induction motor, cage and wound slipring rotor, synchronous and rotor speed, slip, induced voltages in stator winding and rotor barwinding. Electrical machines i video course electrical engineering nptel. Historythe induction motor with a wrapped rotor wasinvented by nikola tesla in 1888 in the unitedstates. Induction motor basics, single phase and three phase. For the latter two technologies, we consider the case of threephase power, which is generally preferred over singlephase because of much higher power density. Ppt threephase induction motor electrical engineering ee. Apr 07, 2020 ppt threephase induction motor electrical engineering ee notes edurev is made by best teachers of electrical engineering ee. Be careful it can hurt to tangle with a three phase motor. Three phase ac induction motors are widely used in industrial and commercial applications.
The speed of rotating magnetic field is synchronous speed, n s r. Pdf speed control of threephase induction motor based. A three phase induction motor runs on a three phase ac supply. Suad ibrahim shahl 26 equivalent circuit model analysis example a 480v, 60 hz, 6pole, threephase, deltaconnected induction motor has the following parameters. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. This paper presents design and analysis of a three phase induction motor drive using igbt. Understand the principle and the nature of single phase and 3 phase induction machines. Circuit diagram for noload and blockedrotor test on 3 phase induction motor a. The rotor of the squirrel cage three phase induction motor is cylindrical in shape and have slots on its periphery.
557 1252 118 182 645 1520 371 538 321 1087 43 989 544 539 1057 1499 744 1268 1302 1297 673 1527 653 293 484 1170 549 586 81 631 1403 818 1037 1357