Definition
A direct-current electric motor whose field is produced by two separate sets of field windings: a series winding connected in series with the armature, and a shunt winding connected in parallel with it. The combination gives the motor strong starting torque from the series winding and steady speed regulation under varying load from the shunt winding.
Plain English
An electric motor that uses two sets of field coils working together — one wired in line with the spinning part for strong pulling power at start-up, and one wired across it to keep the speed steady once it is running.
Context Anchor
Seen in aircraft electrical system and maintenance discussions, especially when describing motors used to move or drive aircraft equipment.
Derivation
‘Compound’ comes from the Latin componere, meaning ‘to put together.’ Here it describes a motor that combines two winding methods — series and shunt — into one design, gaining the strengths of both.
Why Pilots Care
Provides reliable high-torque starting and stable operation under changing loads, which is critical for engine starters and certain flight-control actuators.
Intuition Check
Compound-wound does not mean the motor is simply complicated or damaged. It means the motor has two field-coil connection methods built into it.
Example Sentence 1
The landing gear motor is a compound-wound motor, giving it the torque to start moving the gear and the steady speed to drive it through the full retraction cycle.
Example Sentence 2
Technicians tested the compound-wound motor to confirm both windings delivered the expected voltage under load.