POWER GENERATION
A ship is like a floating city with all the privileges enjoyed by any normal land city. Just like a conventional city, the ship also requires all the basic amenities to sustain life on board; the chief among them is power or electricity. In this article we will learn as to how power is generated and supplied on board a ship.
Power generation On board
Shipboard power is generated using a prime mover and an alternator working together. For this an alternating current generator is used on board. The generator works on the principle that when a magnetic field around a conductor varies, a current is induced in the conductor.
The generator consists of a stationary set of conductors wound in coils on an iron core. This is known as the stator. A rotating magnet called the rotor turns inside this stator producing magnetic field. This field cuts across the conductor, generating an induced EMF or electro-magnetic force as the mechanical input causes the rotor to turn.
The magnetic field is generated by induction (in a brushless alternator) and by a rotor winding energized by DC current through slip rings and brushes. Few points to be noted about power on board are :
- AC, 3 phase power is preferred over DC as it gives more power for the same size.
- 3 phases is preferred over single phase as it draws more power and in the event of failure of one phase, other 2 can still work.
