Three phase Lego generator


Whilst researching solenoids for J5's air systems, I found loads of info about how magnets and copper interact to produce electricity... I became hooked on making electricity.

The 3 phase alternator and delta/star switch developed over time. The current output is 3.5w at 4000 rpm, the alternator is driven by hand and can charge upto 12v batteries.

The delta/star switch changes the output of the generator to give more volts, less amps or less volts, more amps at a given rpm.



The discussion forum Fieldlines is a great resource for information. The discussion group has some very skilled and knowledgeable people who are usually happy to help...
...that is if you use the site search facility to find your answers before posting questions.

My Project

This project is really more of an adventure of discovery, and as such has many stages. The links below are organised chronologically, and you will see the 'evolution' of the generator.

The beginning
Some understanding
4W output
Different configurations
A cautionary tale
16,200 rpm Lego alternator
Dynamic rotor balancing
3 phase alternator with delta/star switch

Please remember, your safety is your responsiblity should you choose to replicate
anything you find on

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