Contents
Why the rotor is called Squirrel Cage?
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 a squirrel cage type rotor?
A squirrel-cage rotor is the rotating part of the common squirrel-cage induction motor. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. The interaction of the magnetic fields of currents in the stator and rotor produce a torque on the rotor.
What is a squirrel cage motor used for?
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.
What are the advantages of squirrel-cage rotor?
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 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 rotor is short-circuited?
To facilitate a closed path in the rotor circuit, both sides of the rotor bars are short-circuited by end rings.
What are the types of rotor?
Type and construction of rotors
- Squirrel-cage rotor.
- Wound rotor.
- Salient pole rotor.
- Non-salient rotor.
- Rotor bar voltage.
- Torque in rotor.
- Induction motor slip.
- Frequency of induced voltages and currents.
What are advantages of cage motors?
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)
Why are squirrel cage motors so reliable?
The interaction of the magnetic fields produced by the stator and rotor windings produces a torque on the squirrel cage rotor. Squirrel cage induction motors are used a lot in industry – as they are reliable, self-starting, and easy to adjust.
What is difference between squirrel cage and induction motor?
In Squirrel cage induction motors the rotor is simplest and most rugged in construction. In slip ring induction motors the rotor is wound type. In the motor the slip rings, brushes are provided. Compared to squirrel cage rotor the rotor construction is not simple.
Which is better squirrel cage or slip ring?
The squirrel cage induction motor is the most popular type of AC motor. It is very commonly used in industries because it is very cheap, robust, efficient, and reliable….Comparison Chart.
| Basis For Comparison | Slip Ring Motor | Squirrel Cage motor |
|---|---|---|
| Power Factor | Low | HIgh |
| Cost | Costly | Cheap |
| Starting Current | Low | High |
What are the two types of rotors?
There are two types of induction motor rotors: Squirrel-cage rotor or simply cage rotor. Phase wound or wound rotors.
How does a non rotating squirrel cage rotor work?
In operation, the non-rotating stator winding is connected to an alternating current power source; the alternating current in the stator produces a rotating magnetic field.
How does magnetic field affect squirrel cage motor?
The interaction of the magnetic fields produced by the stator and rotor windings produces a torque on the squirrel cage rotor. One big advantage of a squirrel cage motor is how easily you can change its speed-torque characteristics. This can be done by simply adjusting the shape of the bars in the rotor.
How can I tell if my squirrel cage rotors are broken?
Inspect the stator as well as the rotor whenever evidence of rotor surface heating is detected. Tap test. Broken fabricated rotor bars may be detected by tap- ping on the bars from one end ring to the other with a hammer and screwdriver. Loose or broken bars will re- spond much differently from tight sound bars.
Why does a squirrel cage have no motion?
If the rotor were to spin at the same frequency, then the magnitude of the force on the rotor bars would equal zero, thus creating no motion. The rotor must always be slower to feel the electromagnetic induction effect as if the rotor is playing a constant game of magnetic “catch-up”.