Definition
An auxiliary winding embedded in slots cut into the pole faces of a DC generator or motor, connected in series with the armature so that current flows through it in the opposite direction to the current in the adjacent armature conductors. This cancels the magnetic field distortion (armature reaction) created by the armature current, keeping the main field uniform across the pole face under varying load.
Plain English
Extra wires set into the face of the magnets inside a DC generator or motor that push back against the magnetic disturbance caused by the spinning armature, so the machine runs smoothly under changing electrical loads.
Context Anchor
Seen in aircraft electrical system and engine accessory maintenance when studying direct-current generators, starters, and motor-generator units.
Derivation
From Latin compensare, 'to weigh against' or 'to balance.' The winding is named for what it does — it balances out, or compensates for, the unwanted magnetic field created by the armature current.
Why Pilots Care
Ensures stable generator output and prevents voltage fluctuations that could affect avionics and instruments during flight.
Analogy
It is like adding a counter-pull in the opposite direction when a load starts twisting something out of line.
Intuition Check
Do not read compensating winding as a setting, adjustment, or correction made by the pilot. In this context, it is a physical coil of wire built into the machine to cancel an unwanted magnetic effect.
Example Sentence 1
The technician inspected the pole faces of the DC generator for damage to the compensating winding after the unit showed excessive brush arcing.
Example Sentence 2
With the compensating windings intact, the generator maintained steady voltage even when all electrical systems were turned on.