Electrical Engineering XYZ MCQs
The size of inter poles is small as compared to main poles, that is because of:
- In order to get more flux
- In order to not get saturated
- In order to get saturated
- All of these
Correct answer: 2. In order to not get saturated
Explanation: In an electrical machine, such as an electric generator or motor, the poles play a crucial role in generating magnetic fields. The main poles are the large poles that are responsible for the main magnetic flux, while the interpole (or inter-pole) is a smaller pole located between the main poles.
The purpose of interpole is to improve commutation in DC machines, particularly in DC motors. Commutation is the process of reversing the current in the armature coil at the right moment as the armature rotates in order to maintain the direction of the magnetic field and, consequently, the direction of the current in the coil. This is important for the smooth operation of the motor.
The statement “The size of interpole is small as compared to main poles, that is because of: In order to not get saturated” is correct. Interpoles are made smaller to avoid saturation. Saturation refers to the condition where the magnetic material (in this case, the pole) is magnetized to its maximum extent and cannot hold any more magnetic flux.
If the interpole were too large, it might saturate, reducing its ability to perform the necessary commutation function effectively. Therefore, keeping the interpole smaller helps prevent saturation and ensures better commutation, leading to smoother and more efficient operation of the DC machine.