USB Bike Generator

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Category: Transport

Published on Tuesday, 01 May 2012 06:13

Written by Administrator

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Here is a great generator I found on Instructables. 

Here is a description that I picked up - you can read more at http://www.instructables.com/id/USB-Bike-Generator/

The USB Bike Generator is a small bike mounted electricity producing device optimized to provide power for two USB ports.  There are so many small electronics that can be powered or charged from a USB connection it only makes since that people might want to do this while riding a bike.  The basic idea for the USB Bike Generator is to use a suitable stepper motor as a generator and a voltage regulator circuit to maintain the 5 volts needed for the USB ports.  In this instructable I will show you how to build this generator and through testing show that it is 70% efficient at converting the power from the generator to the power needed for the USB port. 

This is the third revision of my bike generator project, the first two can be found herehttp://www.instructables.com/id/Bike-Generator/ and here http://www.instructables.com/id/BikeGen/ I would strongly recommend that if you plan on building this USB Bike Generator you at least look over how these past to versions went together.

This third rendition of my bike generator project came about after reading some of the comments made about my previous methods. Specifically, one comment from member ac-dc stated that my decision to use a linear regulator to go from 30 volts from the generator to 3 volts to power the light was at best 10% efficient. Now since one of the interests I've had listed on my profile since I joined this site has been efficiency I decided to read the rest of his comment after wiping the tears from my eyes. Ac-dc suggested that buck switching regulator would be better suited for a bike generator like mine. I had no idea what a switching regulator was so I started to do some research and found out that ac-dc was right and that I could significantly increase the efficiency of the electronics I was using.

In my searching for switching regulators I came across this reference from Dimension Engineering,http://www.dimensionengineering.com/switchingregulators.htm.  They offer a good explanation of the switching regulators and even sell them.