Protection of an induction motor im against possible problems, such as overvoltage, over current, overload, over temperature, and under voltage, occurring in the course of its operation is very important, because it is used intensively in industry. For induction motors a very important parameter is the slip of the motor the slip, s, defines the relative speed difference between synchronous speed and rotor speed and is given by. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. In an induction motor, the electric current in the rotor needed to produce torque is obtained via electromagnetic induction from the rotating magnetic field of the stator winding. Induction motor seminar ppt, pdf report study mafia. Equivalent circuit of an induction motor enables the performance characteristics which are evaluated for steady state conditions. An induction motor can therefore be made without electrical connections to the rotor. A threephase induction motor problem this application note describes how to set up, solve, and analyze the results of a twopole, threephase induction motor using rmxprt.
A three phase, 12 pole, salient pole alternator is coupled to a diesel engine running at 500 rpm. Now tbe machine is loadej so that it is driving a load torque of 100 nm. This troubleshooting guide can also be applied to other types of three phase induction motors. Before discussing, induction motor drives its important to understand and know about induction motors. Induction problems induction problems can be hard to. Different speed control methods of induction motor are explained below. Three phase induction motor or ac motor is started by itself but we require some starter or other methods for proper starting and controlling induction motor. Wind pushes the blades of the turbine, spinning a shaft attached to magnets. How to solve common electric motor problems and get great. Motion and temperature heat control are paramount in energy. Introduction trouble with a motor, like trouble with any otating r machinery, ranges depending on the situation from aggravation to crisis. It is based on freescales 56f800e microcontrollers. Diagnostics of rotor and stator problems in industrial.
The threephase induction motor is the extensively used for various kinds of industrial drives. Sizes vary from fractional horsepower to several thousand horsepower used for such appli. You can control the speed of the induction motor by changing the motor voltage while v while keeping vf consatnt where f is the frequency of the voltage applied on the motor. An induction motors rotor can be either wound type or squirrelcage type. How an induction motor works by equations and physics. Induction motor testing and evaluation summary as energy costs rise, more emphasis is being placed on determining the health of large inductive motors. The armature circuit of the macbine bets a resistance of one fl. Solution a a matlab program to calculate the torquespeed characteristic is shown below.
The rotor will constantly be turning to align its magnetic field with that of the stator field. A fourpole, starconnected, squirrelcage induction motor operates from a variable voltage 50 hz threephase supply. Request pdf main problems and proposed solutions to induction machine drive control of multisystem locomotive this project was motivated by demand of. The threephase induction motor is the extensively used for various. 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. This will link and cut the rotor conductors which in turn will induce a current in the rotor conductors and. Record all nameplate information for the induction motor. Stator line voltage 220 164 112 88 42 stator line current amperes 6. Difference is that transformer is an alternating flux machine while induction motor is rotating flux machine. Here are a collection of statements which can be proved by induction. If the motor problems cant be resolved with this list, please contact your supplier for assistance.
Kanpur, india design of a three phase squirrel cage induction motor for electric propulsion system ravi prakash,mohammad junaidakhtar, r. Starting method for induction motors a 3phase induction motor is theoretically self starting. Induction motors are the commonest type of motor and account for a very large proportion of heavy duty motors. Telecommunication engineering, southwest jiaotong university, china, 2005 thesis submitted for the degree of masters of engineering science in school of electrical and electronic engineering the university of adelaide, australia august 2010. Parida department of electrical engineering national institute of technology, silchar,assam, india email. Induction motor rotor february 17, 2019 february 24, 2012 by electrical4u rotor as the name suggests it is a rotating part of an electrical machine, in which current is induced by transformer action from rotating magnetic field. The stator of an induction motor consists of 3phase windings, which when connected to a 3phase supply creates a rotating magnetic field. As induction motors are widely being used, their speed control may be required in many applications. It supplies an induction motor ich has a full load speed of 144wh 0 rpm. Electric motor failures can be due to mechanical component failure or electrical circuit failure. Induction motor drives starting braking speed control of. A threephase induction motor problem enginuity systems. Electric energy and induction motors the level of prosperity of a community is related to its capability to produce goods and services. Choose editselectobjectby clicking, and then select the object groups phb and phreb.
This mode of operation can be used to quickly stop a machine. In very simple words induction motors can be described as a threephase, selfstarting constant speed ac motors. The induction motor is made up of the stator, or stationary windings, and the rotor. At noload, the slip is nearly zero induction motors which employ squirrel cage rotor are called squirrel cage induction motors. 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 then a three phase rotating magnetic flux is. Explain starting methods of 3 phase induction motor. You should also make a dc measurement of stator winding linetoline resistance using a dmm. The motoring region of the induction machine torquespeed curve is the region of greatest interest. Nov 23, 2015 before troubleshooting the 3 phase induction motor, we must have to know about the 3 phase induction motor, star delta starter and its connection diagram. Ism to accompany electric machinery and power system.
To achieve long motor life in wet environments, like a dairy processing plant, standard motor construction and standard water ingress protection are insufficient. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. An electrical motor is a device that has brought about one of the biggest advancements in the fields of engineering and technology ever since the invention. Induction motor problems and solutions pdf 3 phase induction motor pdf three phase induction motor three phase induction motor diagram speed control of induction motor the wound rotor induction motor blocked circle diagram of an induction motor speed control of induction motor by vf method single phase induction motor pdf free download speed control of three phase induction motor with universal controller principles of induction machines solved problems magnetic induction electromagnetism. Traditional design of cage rotor induction motors ronald g. But producing goods and services is strongly related to the use of energy in an intelligent way.
Ac induction motors are also the most common motors used in main powered home appliances. Design of a three phase squirrel cage induction motor for. The motor is mounted in a test rig that allows one to control the torque applied to the motor shaft and to measure both rpm and torque. There are problems associated with the running of induction motors at reduced voltage. An induction motor also known as an asynchronous motor is a commonly used ac electric motor. Main problems and proposed solutions to induction machine drive. Ueeneeg006a solve problems in single and three phase low. The 3phase set of currents, each of equal magnitude and with a phase. The table below gives the commonly encountered problems in 3 phase squirrel cage induction motors, cause of problems and what remedy to apply to bring the motor back to production. Free download induction motor seminar ppt, pdf report. T1 operating principles of three phase induction motors encompassing. At noload, the slip is nearly zero induction motor im against possible problems, such as overvoltage, over current, overload, over temperature, and under voltage, occurring in the course of its operation is very important, because it is used intensively in industry.
Therefore, motor troubleshooting involves the entire system, not just the. Specific problems that are unique to various motors are also identified. The model created by rmxprt will then be used as an input for empulse as a basis for performing more detailed analysis and for increasing the accuracy of the performance pre. For example, assume that the voltage applied to the motor terminals is.
In section 11, a testing procedure is established that can be followed to determine the fullload noise level of an induction motor. This type of motor is essentially the same as a twovalue capacitor motor operating. Third international conference on advances in control and optimization of dynamical systems march 15, 2014. A 480v, 60 hz, 6pole, threephase, deltaconnected induction motor has the following parameters. Much theory on induction motors has been developed, but the method of analysis employing symetrical components best suits the particular problem at hand. Once the induction motor has any problem, there might be some abnormal phenomena, for instance, the rising temperature, over current, vibration and abnormal noise and so on. The very first thing that you should do before starting any type of maintenance on a motor is a visual inspection, a lot of times the trouble can be found just by looking, because if the problem is that bad then it should be very obvious by observation. Harley and yao duan georgia institute of technology november, 2009. The basic idea of an electric motor is to generate two magnetic fields. The following results were obtained as the supply voltage was gradually reduced with the motor running on noload.
The reason for describing induction motors as constant speed is because normally these motors have a constant speed depending on the frequency of the supply and the. Maintenance and troubleshooting three phase induction motor. So, now principle of induction motor right so, the operation of three phase induction. In the case of an 8pole induction motor, the supply frequency was 50hz and the shaft speed was. The voltage and current is induced in the rotor circuit from the stator circuit for the operation. Find the percentage slip and number of poles of the induction motor. Here we will see a detailed article related to the starting methods of threephase induction motor. An induction motor is based on the principle of induction of voltages and currents. Troubleshooting guide ac motor use this resource to troubleshoot your ac motor. Pdf problems incurred in a vectorcontrolled singlephase. Installation and maintenance threephase induction motors 3 4850 en 2019. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed.
Most texts only have a small number, not enough to give a student good practice at the method. Induction motor fault heading fault causes remedies induction motor a no supply voltage b driven equipment jam c motor shaft jammed. Dec 19, 2009 a very standard induction motor exercise. The stator separate from rotor by small air gap have ranges from 0. Most of single phase induction motors use squirrel cage rotor as it has a remarkably simple and robust construction enabling it to operate in the most adverse circumstances.
Motor current monitoring and analysis mcsa is a straight forward tool to diagnosing problems with large inductive motors. If the motor problems cant be resolved with this list. Why 3phase why not 1ph, 4ph, 6ph, 12ph why 3phase transmission pisquare academy duration. Sfoc of induction motor im drives estimate the mechanical. A 2pole, 3phase induction motor delivers 37 hp at the shaft at a speed of 2850 rpm on. Diagnostics of rotor and stator problems in industrial induction motors by fang duan b. Ueeneeg006a solve problems in single and three phase low voltage machines. Here we are giving you only overview on 3 phases induction motor. The other is the mechanical problems, such as the problems of the bearing, fan blade, motor frame, coupling, end bell, bearing cover, spindle and so on.
This motor benefits from the experience of one of the largest manufacturers in the world, using stateoftheart technology in automation, specially selected materials and rigorous quality control. Induction motor analyses internationalteam workshop problem 30. Pdf induction motors do not run at synchronous speed, they are generally fixed speed motors. How an induction motor works by equations and physics introduction. Induction motor problems and solutions pdf 3 phase induction motor pdf three phase induction motor three phase induction motor diagram speed control of induction motor the wound rotor induction motor blocked circle diagram of an induction motor speed control of induction motor by vf method single phase induction motor pdf free download speed control of three phase induction motor with universal controller principles of induction machines solved problems magnetic induction. Also included is a testing procedure to determine the nature. Introduction this application note describes the design of a 3phase ac induction motor drive with volts per hertz control in closedloop vhz cl. However, it suffers from the disadvantage of a low starting torque. An indepth troubleshooting guide to help you with your ac electric motor issues. This article presents a basic explanation of electric motor construction and. Ac induction motors are also the most common motors used in. An induction motor or asynchronous motor is an ac electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. Problems and premature failures often indicate input power system troubles, poor or deteriorating mechanical installations, or malfunctions in the driven machinery. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation.
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