Working principle of dc motor

Working principle of dc motor

dc motor

The working principle of a DC (Direct Current) motor is based on the interaction between a magnetic field and an electric current. The fundamental concept behind its operation is Fleming's left-hand rule, which relates the direction of the force experienced by a conductor carrying current in a magnetic field.


Working principle of dc motor


Here's how a basic DC motor works:


1. Magnetic Field: The DC motor consists of a permanent magnet known as the stator, which generates a stationary magnetic field.


2. Armature: The rotor or armature of the motor is an electromagnet made of a coil of wire wounded around a core. This armature is placed within the magnetic field and is free to rotate.


3. Commutator: The armature is connected to a commutator, which is a split ring made of conductive material. The commutator is mounted on the same shaft as the armature and rotates with it.


4. Brushes: The stationary brushes are in contact with the commutator. These brushes are made of carbon or graphite and provide an electrical connection between the armature and the external power supply.


5. Electric Current: When an electric current is applied to the armature coil, it becomes an electromagnet. The current flows through the armature coil and generates a magnetic field around it.


6. Fleming's Left-Hand Rule: According to Fleming's left-hand rule, when a current-carrying conductor is placed in a magnetic field, a force is exerted on the conductor, causing it to move perpendicular to both the magnetic field and the direction of the current.


7. Rotational Motion: As the armature's magnetic field interacts with the stationary magnetic field of the stator, a force is generated that causes the armature to rotate. The commutator ensures that the direction of the current in the armature coil is reversed every half-turn, ensuring continuous rotation of the rotor.


8. Control: The speed and direction of the DC motor can be controlled by adjusting the magnitude and polarity of the current supplied to the armature coil.


DC motors are widely used in various applications, such as electric vehicles, industrial machinery, robotics, and household appliances, due to their simplicity, controllability, and reliability.