Working principle of slip ring induction motor pdf

The slip rings brushes allow external resistors to be connected in series with the winding. By putting resistance in series with the rotor windings, the starting current can be kept low while mainta. Working principle of three phase induction motor electrical. When three phase supply is given to the stator winding, a rotating magnetic field of constant magnetic field is produced. The slip ring induction motor working in the induction principle. But how does external resistance aid in better starting characteristics. Learn more about the construction and operation of a slip ring induction motor. The principle of operation of the induction machine is based. The slip energy recovery method provides the speed control of a slip ring induction motor below its synchronous speed. Oct 10, 2016 a wound rotor induction motor is also known as slip ring induction motor. Things like limlsm, hydraulic and pneumatic launch, how catch cars and brakes work, how. Synchronous motor working principle instrumentation tools. This article explains the construction, working principle of singlephase induction motors.

This classification of induction motor is based on the type of power supply required for its operation. Slip ring induction motor fundamentals pnpntransistor. Slip ring we can change the starting torque by simply varying the external resistance connected to rotor, this is not possible in case of squirrel cage induction motor, although squirrel cage is easy to maintain and cost effective as compared to slip ring as it has slip rings,brushes. There are single phase induction motors and three phase induction motors. The major difference between them is that transformer is static in nature i. Induction motor working principle your electrical guide. A synchronous generator is an ac generator in which the output is synchronized to the position of the rotor. In this article, i am going to focus on the working principle of the induction motor.

Slip ring induction motor or wound induction motor or. Slip ring induction motor application, construction, working principle, advantages and disadvantages, speed control of slip ring induction motor, the difference between slip ring i. Starting andcontrol of slipring 5 electrical engineering book. A slip ring induction motor utilizes this property to achieve a high starting torque. A wound rotor induction motor has a stator like a squirrel cage induction motor, but a rotor with insulated windings brought out via slip rings and brushes however, no power is applied to the slip rings. Wound rotor induction motors ac motors electronics. The slip ringsbrushes allow external resistors to be connected in series with the winding. Starting of slip ring induction motor explained in an easy. Squirrel cage motor and ii slip ring motor or wound type.

Slip energy recovery of an induction motor circuit globe. Induction motor working principle types of induction motor. Srim rotor consists of a threephase winding similar to the stator winding, but in scim the rotor consists of bars which are shortened at the ends with help of end rings. Stepper motor is an actuator transforming electric pulse into angular displacement.

The stator of slip ring induction motor is very much the same as that of the squirrel cage induction motor, but the construction of its rotor is very much different. Induction motors have been ruling the industrial world for many decades. Join researchgate to find the people and research you need to help your work. 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. Some of them are even fractional horsepower motors, which are used in applications like small toys, small fans, hairdryers etc. Therefore slip ring induction motors are generally e. The rotor terminals are connected to three slip rings which turn. A slip ring induction motor can be started with external resistance added in its rotor circuit. In normal conditions, the slip ring motor functions like a squirrel cage motor.

Slip ring motor fundamentals brighthub engineering. The stator winding is connected to the three phase supply terminals. Thus the rotor rotates in the same direction as that of stator flux to minimize the relative velocity. The operating principle of an asynchronous motor involves creating an induced current in a conductor when the latter cuts off the lines of force in a magnetic field, hence the name induction motor. What are the applications of a slipring induction motor. Their sole purpose is to allow resistance to be placed in series with the rotor windings while starting figure below.

In slip ring induction motors, higher starting torque can be attained by providing an external resistance in the rotor circuits during the starting period of the slipring induction motor. Y provides smooth and stepless cutting of resistance in rotor circuit of the motor, reducing starting current and increasing starting torque of slipring induction motor. The stator winding can be either deltaconnected or starconnected. Higher is the inertia, higher has to be the accelerating torque, otherwise the start will be very long and the motor can be damaged by the heating. A slip ring can be used in any electromechanical system that requires rotation while transmitting power or signals. Sep 18, 2018 induction motors have been ruling the industrial world for many decades.

The rotor of the slip ring induction motor is also cylindrical or constructed of lamination. Slip ring induction motor advantages disadvantages and. Working principle of 3 phase squirrel cage induction motor. Working principle of an induction motor the motor which works on the principle of electromagnetic induction is known as the induction motor. Slip ring induction motor have big advantage of having high starting torque compared to squirrel cage motor.

The figure below shows the connection and method for recovering the slip energy and power recovery of an induction motor the basic principle of the slip power recovery is to connect an external source of the emf of the slip frequency of the rotor circuit. This cooling type corresponds to the design of a surfacecooled motor with a housing featuring cooling fins and an external fan mounted on the shaft. To overcome this problem, the slip ring induction motor comes into the picture. Pdf design and analysis of drive system with slip ring induction. Instead of bars, in this motor three windings are used. There might be also an interlock provided to ensure the proper sequential operation of the control.

Threephase induction motor protection systems and its. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Wound rotor induction motor the engineering projects. If the slip ring induction motor is started with all the slip rings or the rotor. A wound rotor motor uses three slip rings typically made of copper or a.

In slip ring induction motors, higher starting torque can be attained by providing an external resistance in the rotor circuits during the starting period of the slip ring induction motor. Nov 03, 2019 there are basically two types of induction motor. Induction motor the downside of the slip ring motor is that slip rings and brush assemblies need regular maintenance, which is a cost not applicable to the standard cage motor. Wound rotor with slip rings the rotating magnetic field. Working principle of 3 phase induction motor is explained and from this, why induction motor is self starting, why rotor rotates in same direction as the rotating field are also answered.

This makes the synchronous generator very efficient for producing electrical power for utility companies. A motor is an electromechanical device which converts electrical energy to mechanical energy. Slip ring induction motor srim vs squirrel cage induction. However, the rotor construction of the slip ring motor is quite interesting. I will tell you about the construction of wound rotor induction motor in the first section. Here we will learn how does single phase induction motor work. A single phase induction motor has two types of rotor. A wound rotor or slip ring motor has a 3phase winding, similar to the stator winding. Types of ac motor definition and classification of ac motor. The electromagnetic induction is the phenomenon in which the electromotive force induces across the electrical conductor when it is placed in a rotating magnetic field. 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. Induction motors generally will have low starting torque compared to dc series motor.

Liquid speed controllers can be supplied to provide required slip resistance to the slip ring motors for speed variation special sized electrolyte tank and heat exchangers are provided to dissipate the heat energy generated in electrolyte during variation of speed. 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. Pdf the use of squirrel cage motor for traction has revolutionised the motive. This arrangement in slipring induction motors also reduces the high inrush currents during the starting of an induction motor.

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. The absence of slip ring and brushes make the construction of squirrel cage three phase induction motor very simple, robust, requires less maintenance and eliminates sparking. Slip ring induction motor construction, working, speedcontrol. Single phase induction motors arenot a selfstarting motor, and three phase induction motor are a selfstarting motor. Free download induction motor seminar ppt, pdf report. If the rotor windings are shorted and a start is attempted i.

A wound rotor induction motor is also known as slip ring induction motor. The 3phase set of currents, each of equal magnitude and with a phase. In this chapter, the mathematical model of induction motor based on space vector theory and the principle of indirect foc are presented. If you want to know about the slip ring induction motor. What is the working principle of slip ring induction motor. A slip ring is an electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. Threephase induction motor consists of a stator and a rotor, and there is no electrical connection between these two. This is the basic working principle of induction motor of either type, single phase of 3 phase. The three phase induction motor is the most widely used electrical motor.

A slip ring induction motor can be started with external resistance added in its rotor. Stator winding can be either star or delta connected depending upon the design. This article is devoted to slip ring induction motors. Read here to know about the starting arrangement and the role played by the external resistances in obtaining better starting characteristics. Working principle of three phase induction motor electrical simple. Learn the principle of power factor improvement and evaluating the cost of electricity. However, the rotor never succeeds in catching up the synchronous speed. Advantages and disadvantages of slip ring induction motor. In a slip ring induction motor, both stator and rotor have three phase windings. Three phase slip ring induction motor my tech info. Speed is varied with the help of external resistance, from 50% to 100% of the full speed, 4.

When a 3 phase supply is given to the stator winding it sets up a rotating magnetic field in space. The slip ring induction motor could be used for industrial wires where variable speed and high starting torque are prime requirements. Also know about the qualities of slip ring induction motors. This rotating magnetic field has a speed which is known as the synchronous speed. Induction motor seminar ppt, pdf report study mafia. A 3 phase induction motor has two main parts i stator and ii rotor. A heavy flywheel is fitted in the drive, preferably between the work and any.

Discrete pwm generator based on simple constant vf principle 4. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. Synchronous motor mainly runs on principle of magnetic locking between rotor and rmfrotating magnetic field. Oct 04, 2017 3 phase motor with resistance type starter. The speed of rotating magnetic field is synchronous speed, n s r. These machines are manufactured to work at near unity power factor and at about 95% efficiency. As discussed earlier, a slip ring induction motor is an asynchronous motor, as the rotor never runs in synchronous speed with the stator poles. Production of high starting torque with slip ring induction motor. However, even before i do that, it is important to know the various parts of the induction motor. Construction and principle of operation of dc series motor how to make a wind mill. Wound rotor induction motors ac motors electronics textbook.

Design and analysis of drive system with slip ring induction motor for. In order to start a slip ring motor, the accelerating torque has to be sufficiently higher than the resisting torque. The rotor of the slip ring induction motor is also. Induction motorim operates on the induction type principle where the current from primary winding is transferred to the secondary winding. The working principles and stator construction of the slip ring induction motor are exactly the same as that of the squirrel cage motor. Low starting current when compared to squirrel cage induction motors, 3. Ysalient features y robust and nonflammable construction. The basic idea of an electric motor is to generate two magnetic fields. A simple circuit diagram of the squirrel cage induction motor is shown in the figure. The poles of the stator are arranged in a manner that they create a rotating electromagnetic field when w gives a. The types of induction motor depend upon the input supply. Based on the working principle, there are mainly three types of ac motors.

Working principle of an induction motor circuit globe. Slip ring induction motor working principle electrical mastar. This arrangement in slip ring induction motors also reduces the high inrush currents during the starting of an induction motor. The electromagnetic induction is the phenomenon in which the electromotive force induces across the electrical conductor when it is placed in a. This has made slipring motor application very rare. In case of three phase ac operation, most widely used motor is three phase induction motor as this type of motor does not require any starting device or we can say they are self starting induction motor. Induction motors are the most commonly used motors in most of the applications. An electric motor converts electrical energy into a mechanical energy which is then supplied to different types of loads. It can improve mechanical performance, simplify system operation and eliminate damageprone wires dangling from movable joints.

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. One of the advantages of the slipring motor is that resistance may be inserted in the rotor circuit to obtain high starting torque at low starting current and then cut out to obtain optimum running conditions. The starting of an induction motor does not relate to simple switching alone. The construction of a stator is the same for both the squirrel cage and slip ring induction motor. Single phase induction motor and three phase induction motor. Squirrel cage motors have a rotor with short circuited bars whereas slipring motors have wound rotors having three windings each connected in star. Higher brush and slip ring maintenance required, 5. An induction motor can therefore be made without electrical connections to the rotor. Induction motor is a singlyexcited device that works on the principle of. Srim rotor construction is very complicated but in scim the rotor construction is. Slip ring induction motor srim vs squirrel cage induction motor scim. These stator and rotors are made up of highmagnetic core materials with less hysteresis and eddy current losses. By the way, the induction motor is also called an asynchronous motor because it runs at a speed lower than its synchronous speed. The frequency of the voltage produced by the synchronous generator depends only on the speed at which its shaft is turned and the number of poles it has.

Induction motor works on the principle of electromagnetic induction. One of the advantages of the slip ring motor is that resistance may be inserted in the rotor circuit to obtain high starting torque at low starting current and then cut out to obtain optimum running conditions. Therefore slip ring induction motors are generally employed where load requires high starting torque or good speed control. An induction motor also known as an asynchronous motor is a commonly used ac electric motor. However, it reduces substantially in a slipring motor due to the high impedance of the rotor circuit. Induction motor, synchronous motor and ac commutator motor. Operating principle of three phase asynchronous motors. Slip ring induction motor working principle electrical. A 3 phase induction motor can be used for different applications with various speed and load requirements. It also involves its switchgears to control its starting inrush current.

A slip ring, three phase induction motor rotates at a speed of 1440rpm, when a supply of 400v, 50hz is applied across the stator terminals. The surfacecooling principle in slip ring induction motors ic 411 the standard threephase slip ring induction motor in protection class ip 55 has ic 411 cooling. When two unlike poles are brought near each other, if the magnets are strong, there exists a tremendous force of. However, even before i do that, it is important to know the. These motors are squirrel and slipring type induction motors. Hi friends, in this article, i am going to discuss about induction motor working principle and hoping you will like my effort. The rotor winding terminals are connected to three slip rings which turn with the rotor. Difference between cage rotor and slip ring rotor basic. What are slip rings and why do some motors use them. Difference between cage rotor and slip ring rotor a woundrotor is a type of induction motor where the rotor windings are connected through slip rings to external resistance.

High performance drive a system employed for motion control using electric motor as a prime. We shall study in detail about this type in this article like what is an induction motor, working principle, types, advantages, and applications. A wound rotor induction motor has a stator like a squirrel cage induction motor, but a rotor with insulated windings brought out via slip rings and brushes. Before discussing the theory of operation for the induction motor a. In the second section, i would be throwing light on the operation and working principle of wound rotor induction motor. The rotor of an induction motor can be a squirrel cage rotor or wound type rotor. The rotor is separated from the stator by a small airgap which ranges from 0. The simulation model of the induction motor drive is developed using the principle of indirect foc. A woundrotor motor, also known as slip ringrotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external.

The three phase leads of rotor winding are brought to three slip rings. Construction of three phase induction motor electrical4u. Jul 25, 2019 squirrel cage induction motor working principle. Starting of slip ring induction motor explained in an easy manner. The rotor will constantly be turning to align its magnetic field with that of the stator field. The singlephase stator winding produces a magnetic field that pulsates in strength in a. Popularly, when receiving a pulse signal, the stepper motor will rotate a fixed angle namelystepping angle according to the direction set for the stepper motor. In the induction motors used in lift and hoists, you will see a type of rotor called a slip ring rotor, whereas in most of.