Cost is high ( 3 times compare to squirrel cage) Large Size; Space requirement increases; There is wear and tear. If one line of a three phase induction motor is opened while the motor is running with moderate or light load, it is found that a three phase induction motor has become a single phase motor. This is a disadvantage in applications where rapid startup is required. Adjusting the resistance allows control of the speed/torque characteristic of the motor. The disadvantages of induction motor include the following. Every coin has two coins: Where wound rotor has significant advantages, it also shares some disadvantages on the same platform: At light loads, the power factor used is also limited; As compared to squirrel cage motor, wound motor reflects lesser efficiency and power factor; Sensitivity is reflected in voltage supply towards fluctuations These bearings support the rotor shaft and make it rotate smoothly. Typical applications of wound rotor or slip ring induction motors are crushers, plunger pumps, cranes Cost is high ( 3 times compare to squirrel cage) There is wear and tear. Note: In Slip ring Induction Motor, Stator is wound for 3 phase winding. But rotor can be wound with any number of phases except single phase. Both stator and rotor are wound for the same number of poles. 3. 4) The brushes are not used in an induction motor. It can operate in any environmental condition, and the construction of an induction motor is robust and sturdy. Poor speeds regulation of external resistance of rotor circuit during operation 3. It consists of a cylindrical laminated steel core and a semi-enclosed recess at the outer boundary to accommodate a three-phase insulated winding circuit. This method is not applicable to cage rotor induction motors. The rotor will be wound to match the number of poles that are present in the stator. Rotor Resistance Control is also one of the methods by which we can control the speed of the Induction motor. The rotor also carries a similar three phase star connected winding. A reluctance motor is a type of electric motor that induces non-permanent magnetic poles on the ferromagnetic rotor. High starting current. A wound-rotor motor, also known as slip ring-rotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external resistance. Speed regulation is poor when operated with external resistances in the rotor circuit. Speed regulation is poor when operated with external resistances in rotor circuit Efficiency and power factor 3) It is a highly efficient motor; the efficiency of IM varies from 85 to 95%. 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. The stator of this motor has three phase star or delta connected winding similar to the stator of the squirrel cage induction motor. The rotor of this motor is wire-wound. Similar to the squirrel cage, there are some slots on the outer periphery. It generates torque through magnetic reluctance.. It is a highly efficient motor. 1) The working of an induction motor is straightforward. Solutions for Chapter 19 Problem 25GCA: List two disadvantages of the three-phase, wound-rotor induction motor. The slip-ring induction motor is also called a wound rotor motor. Expensive due to the maintenance cost, like upkeeping the slip rings, rotor windings, and also the carbon brush; The speed regulation is not good while operating with an external resistor in the rotor circuit. Get solutions Get solutions Get solutions done loading Looking for Working Principle of Three-Phase Induction Motor. Disadvantages of Induction motor. Disadvantages of induction motor: The power factor of the motor is very low during light load conditions. Compared with squirrel cage induction motor, the initials and maintenance costs are higher due to the existences of slip rings, brushes and short circuit devices. A single phase induction motor can not generate the rotating magnetic field and hence it is not self starting motor. They are used for loads that requires speed control. Disadvantages of Slip ring Induction Motor. Slip ring induction motor is one of the types of 3-phase induction motor and is a wound rotor motor type. Disadvantages of Induction Motor. Wound Rotor or Slip Ring Induction Motor. This video covers the basic construction and operation of a wound rotor induction motor. The disadvantages: lower starting torque higher starting current The speed of the wound induction motor can be controlled by connecting an external resistance in the rotor circuit through slip rings. This method needs two motor, one of them is wound motor.

In this motor, the rotor includes a laminated cylindrical core. Main disadvantage of squirrel cage induction motor is that they have poor starting torque and high starting currents.

Initial and maintenance costs are more than those of a squirrel cage motor, because a slip-ring induction motor needs 2. The stator winding is overlapped at 120 (electrically) to each other. A motors moment of inertia is proportional to rotor's weight, diameter, and length (or thickness). Shafts and bearings Ball and roller bearings. Therefore, the external resistance cannot connect with the rotor. A wound rotor induction motor is preferred over a squirrel cage induction motor when the major consideration involved is High starting Torque, Low starting current & Speed control over the limited range. The energy is collected through the slip rings connected to the rotor shaft the squirrel cage motors Disadvantages of wound rotor induction motors : 1. In the area of AC Asynchronous motors, you will find us working on AC polyphase squirrel-cage or wound-rotor induction motors (SCIM or WRIM) which offer several advantages including self-starting, low cost, robustness, and reliability. The maintenance of IM is very less compared to the DC motor and synchronous motor. Sensitive to change in supply voltage. The rotor part of the slip ring induction motor is wound type. Some added auxiliaries make the single phase induction motor self starting. Reluctance motor subtypes include synchronous, variable, switched and variable stepping.

Starting torque will be in the order of 1.5 to 2 times the full load torque and starting current is as high as 5 to 9 times the full load current. 2) It is very cheap compared to the other motors. In the case of squirrel cage induction motor, rotor bars are short-circuited with end rings. Reluctance motors can deliver high power density at low cost, making them attractive When a three-phase supply is given to the stator winding, the rotating magnetic field (RMF) induced in the stator circuit. The wound-rotor induction motor is also called a slip ring induction motor. The efficiency of IM is varying from 85 to 95%. Its cylindrical in shape that is laminated by a steel core and a semi-closed groove at the outer boundary to accommodate a 3 phase insulated winding circuit. A slip-ring induction motor is called an asynchronous motor because it does not run at a speed equal to the synchronous speed of the rotor. The speed of the rotating magnetic field is known as synchronous speed (NS). The heat generated during starting is mostly dissipated external to the Brush less DC motors are. More sensitive to the supply voltage regulation fluctuations. The speed of the wound rotor or slip ring induction motor can be controlled by varying the resistance in the rotor circuit. This method is applicable to slip ring induction motor only. When the motor is running and if the full resistance is connected in the rotor circuit the speed of the motor decreases. The induction motor uses ball-and-roller bearings. But rotor can be wound with any number of phases except single phase. The rotor does not have any windings. The major difference is the external resistance circuit for controlling the speed of the motor. The wound rotor provides a higher starting torque as compared to the squirrel cage rotor. Because of various advantages like low initial current, high starting torque, and improved power factor, it is used in applications that require high torque, cranes, and elevators. Speed control is not possible in a squirrel cage induction motor., in short, no speed regulation. Fig.1: Wound Rotor Induction Motor. Advantages of induction motor: It is a very cheap cost compare to the other motors. 2. Slip Ring Induction Motor Disadvantages: 1.

That is, outer-rotor brushless DC motors have a larger moment of inertia about the rotor and so tend to be slower to start because they require more energy to get turning. The heat generated during starting is mostly dissipated external to the motor in the starting resistance. The complication and maintenance associated with brushes and slip rings is a disadvantage of the wound rotor as compared to the simple squirrel cage rotor.

The induction motor takes high reactive power at no load operation and its power factor is very low at no load or light load. Specific types of induction motors achieve this rotation in different ways, and please feel free to read our articles on squirrel cage motors, wound rotor motors, and single-phase industrial motors to learn more. wound rotor induction motors as follows, what are the advantages and disadvantages of induction motors induction motors constitute more than 60 of loads in the industry induction motors have many advantages 14 / 26. and a few disadvantages, when looking to spec a What are the disadvantages of a wound rotor induction motor? Disadvantages. The slip ring induction motors are also used for loads which require a gradual build-up of load. There is sparking; Maintenance is large; Note: In Slip ring Induction Motor, Stator is wound for 3 phase winding. Disadvantages of squirrel cage induction motor : Poor starting torque. Wound-rotor motors can be started with low inrush current, by inserting high resistance into the rotor circuit; as the motor