Introduction: Low Voltage Induction Motor

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Introduction

Induction motors are one of the most widely used types of electric motors. They are simple, rugged, and efficient, making them ideal for a wide range of applications. In this article, we will discuss the starting principle of induction motors in a step-by-step guide.

Step 1: The Stator

The stator is the stationary part of the motor. It consists of a core made of laminated steel, which is wound with copper wire. The wire is wound in a specific pattern, which creates a magnetic field when an alternating current (AC) is passed through it.

Step 2: The Rotor

The rotor is the rotating part of the motor. It consists of a core made of laminated steel, which is also wound with copper wire. The wire is wound in a different pattern than the stator, which creates a magnetic field when an AC is passed through it.

Step 3: The Magnetic Field

When an AC is passed through the stator, it creates a magnetic field that rotates around the stator. This magnetic field induces a current in the rotor, which also creates a magnetic field. The rotor's magnetic field tries to align with the stator's magnetic field, causing the rotor to rotate.

Step 4: Starting the Motor

When an induction motor is started, the rotor is not rotating. Therefore, there is no magnetic field to interact with the stator's magnetic field. To start the motor, an auxiliary winding is used. This winding is positioned at a 90-degree angle to the main winding and is connected to a capacitor.

Step 5: The Capacitor

The capacitor is used to create a phase shift between the current in the main winding and the current in the auxiliary winding. This phase shift creates a rotating magnetic field, which starts the rotor rotating.

Step 6: The Run Winding

Once the rotor is rotating, the auxiliary winding and capacitor are no longer needed. The motor switches to the run winding, which is connected directly to the AC supply.

Conclusion

Induction motors are a simple and efficient way to convert electrical energy into mechanical energy. By using an auxiliary winding and capacitor, induction motors can be started and run smoothly. Understanding the starting principle of induction motors is essential for anyone working with electric motors.


IN NEXT POST, THE SELECTION TOPIC OF AN INDUCTION MOTOR WILL BE COVERED BASED ON THE APPLICATION DETAILS

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