Contents
What is 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.
How does an AC induction motor work?
The magnet fields induced within the rotor are attracted to the magnetic field being produced by the stator, following it as it rotates with each half-cycle of alternating current. This type of motor is called an induction motor because the magnetic field created in the stator induces a magnetic field in the rotor.
What are AC induction motors used for?
Used in almost every process, induction motors are mainly used in water pumps, kitchen appliances, fans and air conditioners, automobiles and common industrial machinery like boiler pumps and compressors.
Why mostly the squirrel cage type induction motor is used?
Squirrel cage induction motors are commonly used in many industrial applications. They are particularly suited for applications where the motor must maintain a constant speed, be self-starting, or there is a desire for low maintenance. These motors are commonly used in: Centrifugal pumps.
Are induction motors AC or DC?
Induction motors, linear motors, and synchronous motors, for example, are all types of AC motors. AC motors can also include variable-frequency drives to control the motor’s speed and torque, while DC motors are available in self-excited and separately excited-type models.
Is AC motor and induction motor same?
The two main types of AC motors are induction motors and synchronous motors. The induction motor (or asynchronous motor) always relies on a small difference in speed between the stator rotating magnetic field and the rotor shaft speed called slip to induce rotor current in the rotor AC winding.
What are the disadvantages of AC motors?
Disadvantages of AC motors The start ability and speed regulation of the AC motor are poor, and it need frequency conversion equipment to adjust the speed; 2. Must be connected to AC power to use, subject to space restrictions.
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.
How does a squirrel cage induction motor work?
We have already discussed that the rotor which is of squirrel cage type has two end rings, which are permanently shorted with the rotor conductors. Thus external resistance could not be added to the rotor circuit. Since the rotor has a very low resistance, the starting torque was very poor.
What is the construction of an induction motor?
The construction of Stator for any induction motor is almost the same. But the rotor construction differs with respect to the type which is specified above. The stator is the outer most component in the motor which can be seen. It may be constructed for single phase, three phase or even poly phase motors.
What are the disadvantages of a squirrel cage motor?
The main disadvantage of squirrel cage induction motor is poor speed control and low starting torque. However, with variable frequency drives, these disadvantages can be overcome.
When was the first induction motor made by Westinghouse?
Although Westinghouse achieved its first practical induction motor in 1892 and developed a line of polyphase 60 hertz induction motors in 1893, these early Westinghouse motors were two-phase motors with wound rotors until B. G. Lamme developed a rotating bar winding rotor.