Definition
A form of energy loss in electrical machines and transformers caused by small circulating currents (eddy currents) induced in the iron core by a changing magnetic field. These circulating currents flow through the resistance of the core material and dissipate energy as heat. Eddy current losses are reduced by building cores from thin, insulated laminations rather than a solid block of iron.
Plain English
Wasted energy that shows up as heat inside the iron core of a transformer or generator. The changing magnetic field stirs up tiny swirling electrical currents in the metal, and those swirls heat the metal up instead of doing useful work.
Context Anchor
Seen in aircraft electrical-system and ignition-system discussions, especially when studying coils, generators, alternators, motors, and metal cores inside electrical parts.
Derivation
An 'eddy' is a small whirlpool or swirl in moving water. The name fits because these induced currents circulate in tiny loops inside the core, much like water swirling in an eddy.
Why Pilots Care
These losses reduce the efficiency of aircraft electrical systems and can cause excessive heating in components like alternators.
Analogy
It is like water swirling in little circles beside the main flow of a stream. The swirl is moving, but it is not helping the water move downstream; it is wasted motion.
Grounding Statement
Picture an electrical coil getting warmer because some of its energy is being spent making tiny unwanted loops of current in nearby metal.
Intuition Check
Do not read losses as a part being missing. Here, losses means useful electrical energy being wasted, mostly as heat.
Example Sentence 1
Generator cores are built from thin, insulated laminations to keep eddy current losses to a minimum.
Example Sentence 2
Minimizing eddy current losses improves the performance of the aircraft's power generation system.