Most of the application of industrial as well as domestic are this type of induction motor. Once the inertia of the load is overcome the rotor is shorted and at that time it is running like an induction motor. Free download induction motor seminar ppt, pdf report. If the slip ring induction motor is started with all the slip rings or the rotor terminals shorted.
Rarely 5% 10% slip ring motors are used in industries because it has several disadvantages like it required. Slip ring motors are the motors of choice whenever high starting torque or low starting current are required. Slip ring induction motors slip ring motor starter moflon. A squirrel cage motor is thus preferred to a slip ring motor. The slip ring induction motor working in the induction principle. The rotor terminals are connected to three slip rings which turn.
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. Speed control of slip ring induction motors part ii. Makwana and others published three phase slip ring induction motor drive with slip power control analysis. These motors are usually started with full line voltage. It is very commonly used in industries because it is very cheap, robust, efficient, and reliable. Is the rotor current in a slip ring induction motor. A wide variety of low speed induction motor options are available to you, such as home appliance, car. The stator construction is the same in both motors. In the case of slip ring induction motor, the construction of stator and rotor is similar. Speed control of wound rotor induction motor using rotor. Matlabsimulink based design and simulation of speed.
Continuous power flowing to the rotor resistor is a considerable heat loss. The starting torque of slipring induction motor can be increased by inserting a suitable in series with the rotor circuit of the motor. Pdf induction motor with outer rotor and ring stator. Construction of three phase induction motor electrical4u. Ch 3 induction motors free download as powerpoint presentation. Aluminum bars are molded in the slots and the bars are short circuited with two end rings. How an squirrel cage motor can be converted to a slip ring. Slip power recovery system in three phase slip ring.
The value of starting current is adjusted by introducing a variable resistance in the rotor circuit. Slip ring motors contents product description 62 overview of technical data 64 motor selection data series srspr variablespeed slip ring motors, continuous duty s1 65 series shsph version for crane applicationsiron and steel works, duty types s3, s4s5 67 bearings 626 terminal boxes 631. Compared to squirrel cage rotors, wound rotor motors are. Good performance, such as high safety, energy saving, compact design, low noise, little vibration, high torque big breakaway torque, reliable operation, stable running and convenient maintenance. As its name indicates stator is a stationary part of induction motor. Slip ring motor conversion to vsd driven standard squirrel. For applications that demand high starting torques, low starting current, or both, baldor is proud to offer abbs broad line of slip ring induction motors. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. The three phase induction motor is the most widely used electrical motor. As discussed earlier, a slip ring induction motor is an asynchronous motor, as the rotor never runs in synchronous speed with the stator poles. Advantages and disadvantages of slip ring induction motor. Induction motor seminar ppt, pdf report study mafia. A slip ring motor also requires a larger space for the motor and its controls.
Speed control of wound rotor induction motor using rotor resistance control aim to use variable resistance in the rotor circuit to control wound rotor induction motor speed theory polyphase induction motors are mainly of two types by construction, squirrel cage and woundrotorwith sliprings. Already since 1927, we are a global manufacturer, supplier, and distributor of large slip ring motors up to 15000 kw and,8 kv. Therefore slip ring induction motors are generally employed where load. The rotor is the rotating part of the induction motor and is mounted on the shaft of the motor to which any mechanical load can be connected. Even by replacing the rotor if you find a way to use the same stator for the new rotor slip ring type there would be a difference in the power rating an. This does not involve the power from on rotor side be fed back to the source. The slip ring induction motor could be used for industrial wires where variable speed and high starting torque are prime requirements. Download fulltext pdf threephase slipring induction motor. In turn, a current is produced in the rotor bars and shorting ring and another magnetic field is.
General purpose slipring induction motors product catalogue. Higher protection classes can be realized on request at any time. Effects of rotor asymmetry conference paper pdf available june 1997 with 3,082 reads. In this project we are going to start and control the speed of. A stator winding is placed in the stator of induction motor and the three phase supply is given to it. But there is no restriction for the direction of phase rotation. The rotor and stator are separated by an air gap which allows free rotation of the rotor. Slip power recovery system for variable speed operation of. Adjusting the resistance allows control of the speedtorque characteristic of the motor. Learn more about the construction and operation of a slip ring induction motor.
Typical induction motor rotors the magnetic field generated in the stator induces an emf in the rotor bars. Based on the construction of the rotor, induction motors are broadly classified in two categories. 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. Slip ring induction motor have big advantage of having high starting torque compared to squirrel cage motor. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. When the injected voltage is in phase opposition with the induced rotor e. First of all, both the motors are different from the construction and design point of view. Threephase induction motors are the most common and frequently encountered machines in industry simple design, rugged, lowprice, easy maintenance wide range of power ratings. The squirrel cage induction motor is the most popular type of ac motor.
Fault identification of 3phase slip ring induction motor. 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. Menzel 3phase slip ring induction motors in protection class ip 55 are designed in the ic 411 cooling class. The slip ring motor has very little application in industries. The rotor is normally connected over a 3 stage resistor bank. Lect 16 electromagnetic induction, faradays law, lenz law.
Pdf three phase slip ring induction motor drive with slip power. Be specially designed for energy saving purpose which is totally enclosed and fancooled type. Induction motors generally will have low starting torque compared to dc series motor. Wound rotor with slip rings the rotating magnetic field. This rotor has a laminated iron core with slots, and is mounted on a shaft. Slip ring motor conversion to vsd driven standard squirrel cage ac motor by j van niekerk, zest weg group over a number of years slip ring motors have largely been replaced by standard squirrel cage ac induction motors, often in conjunction with ac variable speed drives vsds. The catalogue covers slipring induction motors called also wound rotor induction motors that are applied to start a high inertia load or a load that requires a very. Cheap copare to slipring im maintainance is easy cost is less compare to slipring im can use at explosive area starting torque is low compare to slip ring im application.
Slip power recovery system in three phase slip ring induction motor 1. Portland slip ring induction motorsbrush holder problems. The generally humidityprotected motor winding is designed to be in thermal class f and is impregnated using the vpi process. Pdf the starting of threephase wound rotor induction motors by stepped resistances added in the rotor circuit. Slipring induction motorsstarting of i rotor rheostat. 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 resistance. The basic idea of an electric motor is to generate two magnetic fields. The main advantage of slip ring induction motor over the squirrel cage induction motor is that it consist. Starting torque of slip ring motor and induction motor. Stator winding can be either star or delta connected depending upon the design. Slip ring motors are normally used where additional torque is required to overcome the inertia of the load.
Low and high voltage three phase induction motors slip ring rotor fixed brushholderm line date. The controlling resistance is in the form of rheostat connected. Three phase slip ring induction motor my tech info. Based on the construction of rotor part the 3phase induction motors are divided into two types. Installation, operating and maintenance instructions three. Starting and speed control of 3phase slipring induction. In three phase induction motor, the power is transferred from stator to. Slipring motors with resistor starter have been a standard solution to achieve a kind of soft start, when either reduction of start motor current or torque is required, used for 50 years or so. The slipring induction motors are practically always started with full line voltage applied across the stator terminals. Rotor has a winding the same as stator and the end of each phase is connected to a slip ring. This work has developed a steadystate and dynamic mathematical model of three phase slip ring. Pdf smooth starting of slip ring induction motors researchgate. Download fulltext pdf induction motor with outer rotor and ring stator winding for multispeed applications article pdf available in ieee transactions on energy conversion 284.
Our design experience and application expertise have made us a leading manufacturer of high voltage slipring. Squirrel cage motors have a rotor with short circuited bars whereas slipring motors have wound rotors having three windings each connected in star. Starting and control of slipring induction motors electrical. They are especially suitable for heavy load inertia applications. The bars are slanted on a small rotor to reduce audible noise. Fault identification of 3phase slip ring induction motor free download as powerpoint presentation. Traditionally, speed control of slip ring induction motor was achieved through varying the rotor resistance.
Rotor side control of high power slip ring induction motor. Slip ring induction motor working principle electrical. Electromechanical transient of series connected three phase slip ring induction motors. This article is devoted to slip ring induction motors. Woundrotor motors can be started with low inrush current, by inserting high resistance into the rotor circuit. Threephase asynchronous motors with slip ring rotor for low voltage applications. Rotor side control of high power slip ring induction motor using a single thyristor.