Question

State the function of following parts in Induction motor: (i) Stator (ii) Sliprings

Answer 1

In an induction motor, the different components each play a crucial role in the motor's operation. Here's a detailed explanation of the functions of the stator and slip rings:

### (i) Stator

**Function:**

1. **Magnetic Field Creation:**
   - The stator is the stationary part of the induction motor and houses the primary winding or windings. When alternating current (AC) flows through these windings, it generates a rotating magnetic field. This field is crucial for inducing current in the rotor.

2. **Providing a Rotating Magnetic Field:**
   - The stator's windings are usually arranged in such a way that they produce a rotating magnetic field. This rotating field is necessary for the induction process that drives the rotor.

3. **Supporting Electrical Components:**
   - The stator houses electrical components such as windings or coils that are responsible for creating the rotating magnetic field. These windings are typically made of copper or aluminum and are insulated to prevent electrical shorts.

4. **Structural Integrity:**
   - The stator also provides the structural framework that supports the rotor and other internal components. It is fixed to the motor frame and does not rotate.

### (ii) Slip Rings

**Function:**

1. **Connection to Rotor Windings:**
   - Slip rings are used in some types of induction motors, particularly those that are wound-rotor motors (also known as slip-ring induction motors). They provide a continuous electrical connection between the stationary parts (stator) and the rotating parts (rotor).

2. **Allowing External Resistance Control:**
   - The slip rings are connected to external resistors or other control devices. By varying the resistance connected to the rotor circuit through the slip rings, you can control the motor's speed and torque characteristics. This feature is particularly useful during motor start-up or when adjusting performance under varying loads.

3. **Transmission of Electrical Power:**
   - Slip rings transmit electrical power from the stationary part of the motor (through brushes) to the rotating rotor windings. This electrical power is then used to create the magnetic field in the rotor, which interacts with the stator's rotating magnetic field to produce torque.

4. **Maintaining Electrical Continuity:**
   - As the rotor turns, the slip rings ensure that there is a continuous electrical connection between the stationary and rotating parts of the motor. This continuous connection is essential for the proper functioning of the rotor windings and, consequently, the entire motor.

In summary, the **stator** generates the rotating magnetic field that drives the rotor, while the **slip rings** facilitate the connection between the rotating rotor and the external electrical circuits, enabling control of the motor's performance.

Answer 2

Sure! Here’s a brief overview of the functions of the parts you mentioned in an induction motor:

**(I) Stator:**
- **Function:** The stator is the stationary part of an induction motor. It contains the windings or coils connected to the power supply. When alternating current (AC) flows through these windings, it generates a rotating magnetic field. This magnetic field induces a current in the rotor, which leads to torque and causes the rotor to turn.

**(II) Slip Rings:**
- **Function:** Slip rings are used in wound-rotor induction motors (also known as slip ring induction motors). They provide a means to connect external resistors or other components to the rotor windings while allowing the rotor to rotate. The slip rings are mounted on the rotor shaft and maintain electrical contact with the rotor windings through brushes. By varying the external resistance connected to the slip rings, the motor’s starting torque and performance characteristics can be adjusted.

Feel free to ask if you need more details!