DC Dynamo
A dynamo is a motor run backwards: turn the coil and you generate current instead of consuming it. This simulation shows the coil rotating in the field, the EMF trace building and collapsing, and the split-ring commutator flipping the connection to keep the output one-directional.
How to use this simulation
- Change how fast the coil is turned
- Adjust the number of turns and the field strength
- Compare the commutator output with slip-ring AC output
What to look for
- Induced EMF is greatest when the coil plane lies parallel to the field
- EMF falls to zero twice per revolution, at the points where flux is momentarily unchanging
- The commutator turns alternating EMF into a one-way pulsating output
The physics behind it
As the coil rotates the flux threading it changes, and Faraday's law gives an induced EMF equal to −N·dΦ/dt. That EMF is naturally sinusoidal, peaking when the coil sweeps through the field fastest. The commutator reverses the external connection every half turn, folding the negative half of the sine wave up into the positive, which yields pulsating DC.