Explanation:

A squirrel cage induction motor is a type of AC motor that is widely used in various industrial applications. It has a simple and robust construction, making it reliable and efficient. In a squirrel cage induction motor, the rotor conductors are short-circuited via end rings.

Why are the rotor conductors short-circuited via end rings?

The short-circuited rotor conductors are an essential part of the motor's operation. When an AC voltage is applied to the stator windings, it creates a rotating magnetic field. This rotating magnetic field induces currents in the rotor conductors, also known as rotor bars.

These induced currents in the rotor conductors create a magnetic field that interacts with the stator magnetic field, producing torque and causing the rotor to rotate. The short-circuiting of the rotor conductors via end rings allows the induced currents to flow freely and complete their circuit.

Advantages of short-circuited rotor conductors:

- Efficiency: The short-circuited rotor conductors help in reducing the losses in the motor. The currents induced in the rotor conductors are circulating currents, which do not produce any power loss. This results in higher efficiency of the motor.

- Starting torque: The short-circuited rotor conductors provide a high starting torque. When the motor is initially started, the rotor conductors experience a high slip, which generates a large torque. This torque is necessary to overcome the inertia of the load and accelerate it to the synchronous speed.

- Robust construction: The short-circuited rotor conductors, along with the end rings, form a solid and sturdy structure known as the squirrel cage rotor. This construction is highly resistant to mechanical stress and provides excellent durability to the motor.

- Low maintenance: The short-circuited rotor conductors do not have any moving parts, brushes, or slip rings. This eliminates the need for regular maintenance and reduces the chances of failure or breakdown.

In conclusion, the rotor conductors in a squirrel cage induction motor are short-circuited via end rings. This arrangement allows the induced currents in the rotor conductors to flow freely, resulting in efficient operation, high starting torque, and low maintenance requirements for the motor.