Bicycle Generator

thingiverse

I am going to retro-fit my bicycle indoor trainer with a generator using a pair of low KV outrunner brushless motors. I will rectify three phase output using Schottky diodes and feed it into a DC-DC regulator. My target power output is around 45 watts, although actual power has yet to be measured. I also have another version that uses two 36W DC generators made in TANWAN. The 30mm roller was too small, causing me to easily exceed the 35V limit of my DC-DC converter and blow a capacitor. Additionally, it required a bit of torque to get started. I recommend using a 60mm roller for this setup. Initial testing with a 20W USB cigarette lighter charger test load looks promising. Not surprisingly, the purpose-built DC generators performed as expected, supplying 30V to the regulator with ease. The brushless motors did an acceptable job, although they required a fairly high RPM and what felt like more torque than necessary. Both setups were able to supply the required 20W to charge two iPads efficiently.