Double cage induction motor

Squirrel cage motors are the most commonly used induction motors , but the main drawback in them is their poor starting torque due to low rotor resistance. Here in this equation the starting torque of induction motor Tsh is proportional to rotor resistance R2. But the thing is that squirrel cage induction motor has very low starting torque due to its rotor resistance of very low value.

Double cage induction motor is used for cage rotor to increase rotor resistance so higher starting torque can achieve by this method.

Double Cage Induction Motors have two cages in the rotor.

In case of 3Ø squirrel cage motor has low starting torque.

This is due to the low Rotor Resistance.

Then, the starting torque with increase but at the same time their will be more copper loss and n of motor will decreases. The double cage motor is so develop that it overcomes the above difficulties and given . The simulation of double cage induction motor provides the base for the design of the squirrel cage induction motor to prevent desing error and mistakes in its construction and testing so as to obtain maximum efficiency. This paper presents the advantage of double cage rotor over the single cage rotor induction . An induction motor with two rotor windings or cages is used for obtaining high starting torque at low current.

In double cage rotor there are two layers of bars as shown: The . One of the main drawbacks of the squirrel cage induction motor is that it has very low starting torque.

Hence, for applications requiring high starting torques, the slip ring motor is the only choice. The study is carried out using FEM analysis. Three double rotor bar induction motors have been simulated and their electromagnetic characteristics are compared to each other.

Keyword: broken rotor bars, double - cage induction motors , interbar currents. EQUIVALENT CIRCUITS FOR DOUBLE - CAGE INDUCTION MOTORS. University of Grenoble, Grenoble, France.

It is shown that, if the classical general equivalent circuit for double squirrel-cage motors is accepte there is a. The measured resistance and reactance at different frequencies are the data of the minimization error function to be minimized for single- and double - cage model.

As name suggests , double cage IM had two cages. One for Starting purpose and another for normal operation. Outer cage is having high resistance and low inductance while inner cage is having low resistance and high inductance.

After releasing the blockage, the by now heated motor is started up again. However, the mechanical stress caused by the increased .