Fall 2005 ee595s electric drive systems 36 the plan continued achieving 14. An843, speed control of 3phase induction motor using pic18 mcus. A single phase induction motor consists of a single phase winding which is mounted on the stator of the motor and a cage winding placed on the rotor. The speed which is desired is obtained at the output of the proposed system by comparing the reduced speed with reference speed of the induction motor. Design of vfd drive for a 3phase induction motor open. Ac motors singlephase 3phase minneapolis, mn rapid. It is available from fractional horsepower ratings to megawatt levels. Assignment i visvesvaraya technological university. Gradually apply three phase voltage across motor stator terminals via the autotransformer d. 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. Three phase induction motor using written pole technology, main winding, exciter winding, control circuit for optimum utilization. Equations 1 3 represent the currents that ow in the three phase windings.
Nptel syllabus advanced electric drives video course course outline. In the case of three phase ac alternating current operation, the most widely used motor is a 3 phase induction motor, as this type of motor does not require an additional starting device. To understand the rotations of magnetic field consider a 2pole 3phase stator as. Fig1 block diagram of scalar vf control technique for the speed control of induction motor 3. Note that starting current is as large as five times the fullload current but starting torque is just equal to the. Starting methods for singlephase induction motor nptel. Introduction types of electrical machines types of 3ph induction motor basic principle working principle compnents of induction motor application comparision between 1ph i. Like synchronous machine, the stator winding of an induction machine is. Working principle of a single phase induction motor circuit. Chapter 3 induction motor and different speed control methods page no 3. Threephase induction motor protection systems and its. Induction motor output, losses and efficiency my tech info. Methods of starting three phase induction motors as we know, once a supply is connected to a three phase induction motor a rotating magnetic field will be set up in the stator, this will link and cut the rotor bars which in turn will induce rotor currents and create a rotor field which will interact with the stator field and produce rotation. Design methodology the design process of induction motor is an iterative process.
Double field revolving theory ac current flows through the stator two fields are generated 1f forward rotating field 2bbackward rotating field pulsating field due to various magnitudes of field at diff time 2 3. It is a single phase motor and its rotor is made of ferromagnetic material. Difference is that transformer is an alternating flux machine while induction motor is rotating flux machine. Three phase induction motor working principle in tamil youtube. Mostafa elshahed objectives learn a brief history of the electrical power systems construction. Phasor diagram of induction motor on noload and loaded conditions, visualization of a three phase induction. Frequency of supply to the induction motor f pn120 12. Record all nameplate information for the induction motor. Air gap length is a major part of induction motor design. Jul 18, 2017 3phase induction motor working principle of operation in tamil with demonstration. Nptel provides elearning through online web and video courses various streams. Differentiate between the various types of generating electric power stations. Frequency of supply to the induction motor f pn120 12 x 500 120 50 hz. Construction of three phase induction motor electrical4u.
List two problems each associated with over voltage and under voltage in a three phase induction motor. A pulsating magnetic field is produced, when the stator winding of the single phase induction motor shown below is energised by a single phase supply. Explain how a rotating magnetic field is produced when the stator of a three phase induction motor is supplied from a symmetrical three phase supply. The induction motor receives power from the supply mains through the stator windings. These are excited by a balanced three phase voltage supply. Single phase induction motor the single phase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills, compressors, pumps, and so forth. The different is the motor requires five phase ac supply to operate and the stator consists of five sets of winding. Single phase induction motors have non zero running torque. To do so, a vfd variable frequency drive is used for controlling the speed of a three phase induction motor with variable load attached to the motor. Single phase induction motors questions and answers. What is major difference between a 3 phase induction motor and a single phase induction motor. The phase currents waveforms of the two phase induction motor ac current control in steadystate were by measuring on the real motor checked. Because of the high efficiency and low cost, 3 phase ac induction motors are the most common type of motor found in industrial applications.
The machine designer first assumes the efficiency and power factor at the rated condition. There are two basic reasons for the use of single phase motors rather than 3 phase motors. The power from the stator winding is transferred to rotor, via air gap by induction principle. This soft start of induction motor is the modern method of starting that reduces the mechanical and electrical stresses caused in the dol and stardelta starters.
Multi phase induction motors types, their working and. One single phase wattmeter plus miscellaneous apparatus as needed. Threephase induction motor, cage and wound slipring rotor, synchronous and rotor speed, slip, induced voltages in stator winding and rotor bar. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. A hysteresis motor is constructed of five main components. Starting behavior of a hysteresis motor is like a single phase induction motor and running.
This application note also covers the basics of induction motors and different types of induction motors. Nptel syllabus electrical machines i video course course outline synchronous machines. For reason of economy, most houses, offices and also rural areas are supplied with single phase a. Vvvf adjustable speed drives for induction motors both sixstep and pwm. Nptel syllabus electrical machines i video course course outline. Speed control shunt and separately exicited motor download. Nov 27, 2019 an electrical motor is an electromechanical device which converts electrical energy into mechanical energy. By default, the block sets the simulation type parameter to continuous to use a continuous sample time during simulation. One way is to alternately connect a small induction motor to the terminals of each of the two. In a balance or symmetrical five phase induction motor, the five groups.
The block uses the three phase input voltages to regulate the individual phase currents, allowing control of the motor torque or speed. List and describe the more commonly used equipment in an electric substation. Rotating flux is only possible when 3 phase voltage or poly phase which is 120 degree apart in time is applied to a three phase winding or poly phase winding 120 degree apart in space. Theory and analysis of three phase induction motor using. Induction motors the singlephase induction motor is the most frequently used motor in the world most appliances, such as washing machines and refrigerators, use a singlephase induction machine highly reliable and economical figure 1 singlephase induction motor. Electrical machines i video course electrical engineering nptel. The main winding of a single phase induction motor produces a magnetic field. The three phase induction motor is also called an asynchronous motor and it is the most commonly used type of motor in industrial applications. They run at a constant speed from noload to the full load. Right from its inception its ease of manufacture and its robustness have made it a very strong candidate for electromechanical energy conversion. This 3 phase motor starter consists of two major units. Specifically, the squirrel cage design is the most extensively used electric motor in industrial applications.
The principle of rotating type phase sequence indicator is like that phase motor. Single phase machines are restricted to small power levels. The main aim of the project dealt with the concept of speed control of a three phase induction motor with energy saving. Constructional features and principle of operation.
Noload and blocked rotor test on an induction machine aim. Speed control of single phase ac induction motor possible. Mutilevel converterfed induction motor drive utility friendly induction motor drive 02 03 03 02 01 01 4 control of synchronous motor self controlled synchronous motor vector control of synchronous motor 02 02 nptel. While researching on the internet i came across this one circuit that proposes a model that uses a microcontroller and a triac circuit and a. You should also make a dc measurement of stator winding linetoline resistance. Induction machines guru nanak dev engineering college. Introduction induction motors are employed in textile mills, agriculture and almost all the manufacturing industries to drive the loads because of its rugged construction and ease operation. This limits the starting current to the induction motor by using thyristors. Thus, we can say, this kit is the heart of the proposed system. Find the percentage slip and number of poles of the induction motor. Learn for free, pay a small fee for exam and get a certificate.
Modeling, simulation and implementation of a abstract this paper presents a comprehensive simulation model of a five phase induction motor drive system. Disconnect any mechanical load connected to the induction motor. Hi all, so im working on a project titled controlling the speed of a single phase induction motor. Umanand, principal research scientist, power electronics group, cedt, iisc bangalore for more details on nptel visit. Induction machines 1 introduction the induction machine was invented by nikola tesla in 1888.
It nds very wide usage in all various application areas. Nov 27, 2019 the three phase induction motor is the most widely used electrical motor. Rotating and pulsating field, development of equivalent. Three phase induction motors are run at a constant speed from no. Nptel, online courses and certification, learn for free. The measurements was made on a small two phase motor designed for operation at rms phase currents of 0,3 a for different speeds. For this motors, we require three phase power supply, whereas thus three phase power must be supplied in a sequence. It has i a squirrelcage rotor identical to a 3 phase motor ii a single phase winding on the stator. Design of a three phase squirrel cage induction motor for. Single phase induction motor double revolving field theory the three phase induction motor starting torque inversely depends on the slip this implies that a small positive slip 0. This strange behavior of single phase induction motor can be explained on the basis of doublefield revolving theory. The induction motor block implements a three phase induction motor. Circuit diagram for noload and blockedrotor test on 3 phase induction motor a. A short module 3 hours, design and creativity, tata motors.
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. Various starting methods used in the singlephase induction motors, with the intro duction of additional features, like the addition of another winding in the stator. A 3 phase induction motor can be used for different applications with various speed and load requirements. All we need to do is to keep daxis stator current constant. Further, in an induction machine, the windings are not all located in the same. Jan 03, 2016 a single phase induction motor is very similar to a 3 phase squirrel cage induction motor. Starting of 3 phase induction motors, high starting. The single phase motor stator has a laminated iron core with two windings arranged perpendicularly. A three phase, 12 pole, salient pole alternator is coupled to a diesel engine running at 500 rpm. Note down the machine ratings and calculate rated current of the machine noload test. Five core disciplines were identified, namely, civil engineering. Rotating and pulsating field, development of equivalent circuit based on double revolving field theory, torqueslip.
938 735 551 595 650 1339 1087 1427 857 1237 834 689 14 252 1223 30 286 60 1385 1499 865 1184 462 325 276 73 547 1001 1398 991