Table of Contents
Squirrel Cage Induction motors are cheaper in cost compared to Slip Ring Induction motors. Requires less maintenance and rugged construction. Because of the absence of slip rings, brushes maintenance duration and cost associated with the wear and tear of brushes are minimized.
What are the advantages of cage motor?
Advantages of Squirrel Cage Induction Motor They are low cost. Require less maintenance (as there are no slip rings or brushes) Good speed regulation (they are able to maintain a constant speed) High efficiency in converting electrical energy to mechanical energy (while running, not during startup)Aug 19, 2020.
What are the advantages of squirrel cage induction motor?
Some advantages of squirrel cage induction motors are: Simple and rugged construction. The low initial as well as the maintenance cost. Maintains constant speed. The overload capacity is high. Simple starting arrangement. High power factor. Low rotor copper loss.
What are the advantages of wound rotor induction motor?
Wound Rotor Induction Motor Qualities Excellent starting torque for high inertia loads. Low starting current compared to squirrel cage induction motor. Speed is the resistance variable over 50% to 100% full speed. Higher maintenance of brushes and slip rings compared to squirrel cage motor.
What are the advantages and disadvantages of wound rotor over squirrel cage rotor in induction motor?
As a result the inrush current is reduced. Another important advantage over squirrel-cage motors is higher starting torque. The speed and torque characteristics of a wound-rotor motor can be adjusted by changing the external resistance, unlike a squirrel cage motor which has a fixed characteristic.
What are the main advantage and disadvantage of a cage motor?
Squirrel Cage Induction Motors requires less conductor material than slip ring motor, hence copper losses in squirrel cage motors are less results in higher efficiency compared to slip ring induction motor.
Which motors has high starting torque?
Series wound DC motors are best for applications that require high startup torque, without the need for speed regulation. Like a shunt motor, as a load is applied to a DC series motor, the motor speed decreases, which reduces the back EMF and increases the net voltage.
Why it is called squirrel cage induction motor?
Squirrel cage motors are a subclass of induction motors, which harness electromagnetism to generate motion. They are so-called “squirrel cage” motors because the shape of their rotor – the inner component connected to the output shaft – looks like a cage.
What is difference between squirrel cage and induction motor?
Key Differences Between Slip Ring & Squirrel Cage Induction Motor. The motor whose rotor is wound type such type of motor is called slip ring induction motor, whereas the squirrel cage motor, has a squirrel cage type rotor. The starting torque of the slip-ring motor is high, whereas in squirrel cage motor it is low.
What is the difference between slip ring and squirrel cage induction motor?
The slip ring induction motors have high starting torque with low starting current whereas squirrel cage motors have low starting torque and high starting current. Slip-ring motor has smooth acceleration under heavy loads as compare to the squirrel cage motor.
Why the wound rotor induction motor is rarely used?
Poor starting torque and cannot be improved. The rotor is wound rotor type with its terminal ends connected to 3 slip rings on the output shaft. The rotor is skewed rotor type with its terminals are short-circuited at end rings.
Why rotor slots are skewed?
The rotor or stator slot of the induction motor skewed through some angle so that the bars lie under alternate harmonic poles of the same polarity or other words, bars must be skewed through two pitches. The main purpose of skewing is to reduce the magnetic logging between the starter and the rotor.
What is the drawback of rotor Rheostatic speed control method?
The major disadvantage of the rotor resistance control method is that the efficiency is low because of the additional losses present in the resistors connected within the rotor circuit. The efficiency is greatly reduced at low speeds because of the higher value of the slip.
What are the advantages of wound rotor over squirrel cage?
The wound-rotor motors have the following advantages over the squirrel cage motors : (i) High starting torque and low starting current. (ii) Smooth acceleration under heavy load. (iii) No abnormal heating during starting.
What is the difference between squirrel cage and wound rotor?
Difference squirrel cage rotor and wound or slip cage rotor This rotor is in the form of bars which are shorted at the end with the help of end rings. In squirrel cage rotor no slip rings or brushes. In wound or slip rotor slip rings and brushes are used. It has a simple construction.
Why the starting torque of squirrel cage induction motor is low?
It suffers from the disadvantage of a low starting torque. It is because the rotor bars are permanently short-circuited and it is not possible to add any external resistance to the rotor circuit to have a large starting torque.
What is the main disadvantage of synchronous motors?
Disadvantages or Demerits: Synchronous motors requires dc excitation which must be supplied from external sources. Synchronous motors are inherently not self starting motors and needs some arrangement for its starting and synchronizing. The cost per kW output is generally higher than that of induction motors.
What are the disadvantages of electric motors?
Disadvantages :- Some fuel is required to make it work and also initial torque must be supplies. Humming noise is also a very big problem. Smoke is also released when it works which is harmful for environment.
What is advantage and disadvantage of induction motor?
Induction motors always operate under lagging power factor and during light load conditions they operate at very worst power factor (0.2 to 0.4 lagging). Some of the disadvantages of poor power are increase in I2R losses in the system, reduction in the efficiency of the system.
Which motor has high starting current?
The induction motor draws a high starting current as compared to the running condition. The starting current of the induction motor is about 5 or 6 times the motor full load current.
Which applications require high starting torque?
Which of the following application requires high starting torque? Lathe machine. Centrifugal pump. Locomotive. Air blower.
Which motor is used for constant speed and high starting torque?
The speed of slip ring induction motor can be changed up to 50% of its normal speed. Slip ring induction motor is used for those industrial drives which require high starting torque and speed control such as lifts, pumps, winding machines, printing presses, line shafts, elevators and compressors etc.
