Why armature core is laminated

Answer Explanation Answer is: Reduce armature voltage drop. C generator should run in clockwise direction only?

Protect brushes from damage. Protect the residual magnetism. Avoid short circuit in armature. Avoid over loading of generator. Answer Explanation Answer is: Protect the residual magnetism. Connect more loads. Reduce commutation effect. This induced EMF causes current to flow, known as eddy current.

Eddy currents are a form of magnetic loss, and the power loss due to the flow of eddy currents is referred to as eddy current loss. Hysteresis loss is another component of magnetic loss. These losses produce heat and reduce motor efficiency. The development of eddy currents is influenced by the resistance of the material in which they flow. More Electrical Machines Questions Q1. An 8-pole, 3-phase induction motor operates from a supply whose frequency is 50 Hz.

Calculate the speed at which the magnetic field of the stator is rotating. In a synchronous motor, the value of coupling angle depends on:.

In which of the following tests, which may be used to measure the synchronous impedance, should the reading be taken in a short time to avoid armature overheating? A 3-phase induction motor has a slot, 9-coil, 4-pole stator. Calculate the number of coils per phase. The thickness of lamination which reduces eddy current loss in electrical machine varies from: Select the closest range.

A V, 4-pole wave wound DC series motor has conductors on its armature; it has armature and series field resistance of 0. The motor takes a current of 30 A. Estimate its gross torque developed if it has a flux per pole of 25 mWb. If the alternator is over-excited and it delivers reactive power to the infinite bus, then under this condition:.

When a synchronous motor is over excited, the drawn power factor current will be:. Testbook Edu Solutions Pvt. Our Apps.