3 ms·

Black start wasn't problem as the current draw from the PIC waking up to check vref was so tiny it didn't stop the system charging (so long as there was a base

Black start wasn't problem as the current draw from the PIC waking up to check vref was so tiny it didn't stop the system charging (so long as there was a base line minimum amount of vibration). I forget the minimum amount but so long as there was more than say 20 mG (milli-gravity) of vibration acceleration then it could harvest from empty.

jacquesm 3y ago
That's super cool. Lots of these systems never get past the blackstart issue and I think that pre-charging the system is cheating because if the system then ever goes for a long time without enough energy input it will die for real. So really neat to see your system did not suffer from that.
- simonbarker87 3y ago
  Thanks, to answer your other question (that I somehow missed). This project was with totally off the shelf components - it basically formed the back bone to my literature review as current state of the art. However, the research group I was in was focussed on using silicon carbide devices for hostile environment sensors (think high temp gas sensors primarily) and looking at how to make FETs from SiC that could work in high temp/high radiation environments etc. This is why my thesis and papers primarily focussed on testing energy harvesting devices at temperature - batteries won't work at 300degC and running power cables up and into a volcano fumarole is a tad awkward. I had this feeling though that if I didn't get a room temperature, off the shelf components, system working I would have missed a key part of the learning - I just got lucky that the system was novel enough for a paper publication.
  - jacquesm 3y ago
    Thank you for the answers. I'd love to see an open source energy harvester, especially if it is based on off the shelf components. Low power sensors without a battery would be a major plus for the environment.

3 ms·

Black start wasn't problem as the current draw from the PIC waking up to check vref was so tiny it didn't stop the system charging (so long as there was a base

by simonbarker87 3y ago

jacquesm 3y ago
That's super cool. Lots of these systems never get past the blackstart issue and I think that pre-charging the system is cheating because if the system then ever goes for a long time without enough energy input it will die for real. So really neat to see your system did not suffer from that.
- simonbarker87 3y ago
  Thanks, to answer your other question (that I somehow missed). This project was with totally off the shelf components - it basically formed the back bone to my literature review as current state of the art. However, the research group I was in was focussed on using silicon carbide devices for hostile environment sensors (think high temp gas sensors primarily) and looking at how to make FETs from SiC that could work in high temp/high radiation environments etc. This is why my thesis and papers primarily focussed on testing energy harvesting devices at temperature - batteries won't work at 300degC and running power cables up and into a volcano fumarole is a tad awkward. I had this feeling though that if I didn't get a room temperature, off the shelf components, system working I would have missed a key part of the learning - I just got lucky that the system was novel enough for a paper publication.
  - jacquesm 3y ago
    Thank you for the answers. I'd love to see an open source energy harvester, especially if it is based on off the shelf components. Low power sensors without a battery would be a major plus for the environment.