6 ms·
Naively I would have guessed you include something like a 1kW resistor + heat sink package, and divert to that. Assuming such parts exist, are they just cost p
by mik3y 12y ago
Naively I would have guessed you include something like a 1kW resistor + heat sink package, and divert to that.
Assuming such parts exist, are they just cost prohibitive, or is there more to it?
(Thanks for taking questions!)
- skdoo 12y agoYes, but the added weight of something as large as a 1kW resistor compromises the portability of the board. We're looking into how to do this without adding weight.
- tomsaffell 12y agoWould it be possible to arc it over an air gap? I.e. allow the energy be dissipated over the resistance of the air? I have no idea whether the power numbers work out, and maybe you'd need to step up the voltage, which adds complexity. Just a thought..
- skdoo 12y agoInteresting idea. I think you won't be able to dissipate enough heat this way, but I'm not sure.
- mikeyouse 12y agoA bit of a higher price point, but some Formula 1 teams went through similar issues with their KERS system in regards to performance and weight. I think everyone converged on extremely high speed flywheels, but there was a fair amount of work into ultracapacitors. I'd imagine a 1,000F ultracap could handle the ~20-30 seconds of 100W braking power at well under a pound? I know nothing of their reliability or availability and I'm sure you guys have done your own research but just thinking out loud.
- skdoo 12y agoThere are some excellent cells out there developed for KERS. One example: http://www.ebaracus.com/product/a123-ahr18700-f1-kers-cells http://www.ebaracus.com/product/a123-ahr18700-f1-kers-cells
- beambot 12y agoRandom thought: Would it be possible to incorporate a resistor directly into the board stackup -- eg. the "board" part itself becomes a large carbon resistor?
- skdoo 12y agoCool idea! I'm not sure about the conductivity or thermal properties of structural carbon fiber, but it may end up being a good option.