12 Volt Dynamo.doc

How does a Bicycle Dynamo Work? Inside the dynamo a permanent magnet is rotated in the middle of some coils of wire. Rotating the magnet instead of the coils has the advantage that slip rings are not needed. The rotating magnet produces a and this generates electricity in the coils of wire.

The top of the dynamo is touched against the rim of the type which rotates when the bicycle is moving. Simple generator A simple generator is similar to an electric motor. With a motor, we put electrical energy in and get rotational energy out. With a generator we put rotational energy in and get electrical energy out.

As with the motor, the current direction changes with each half turn of the generator. The generator produces alternating current because slip rings are used in place of a split - ring commentator.

The slip rings keep a continuous connection with the wire around the armature (continued). If a simple electric motor with a split - ring commentator is used to generate electricity, you do not get alternating current. A different type of electrical output is produced.