3D Dynamo - Multicoils
Several coils sit on the same shaft at equal angular spacings, each with its own pair of commutator segments. Because they reach their peaks at different instants, the terminal output follows whichever coil is nearest its peak, and the deep dips of the single-coil machine are filled in.
How to use this simulation
- Use the angle slider to hand over from one coil to the next and see the switch happen
- Run the machine with the speed slider to watch the combined output settle
- Follow one coil's own EMF curve against the smoothed terminal output
- Orbit the 3D view to count the coils and the commutator segments serving them
What to look for
- The output never falls to zero any more — it ripples between a floor and the peak
- Handover happens where two coil curves cross, which is the lowest point of the ripple
- More coils means a shallower dip and a mean output closer to the single-coil peak
- Each individual coil still produces an ordinary sine — the smoothing is done by the commutator
- The ripple repeats several times per revolution, not once
The physics behind it
Each coil generates ε = NBAω sin(ωt + φ), with φ fixed by where it sits on the shaft. For n coils those offsets are 180°/n apart, and the commutator hands the load whichever coil is closest to its peak at that moment. The output therefore only ever dips from ε₀ down to ε₀ cos(90°/n) before the next coil takes over. Raising n lifts the mean EMF towards ε₀ and shrinks the remaining ripple sharply.