PPPM Power Board

[solitonbeat]

From what I have read, most 12v Inverters automatically shut down at 15v. How do you manage to have your inverter working flawlessly with a 15v ultracapacitor has source?

[mjnesbitt]

15 volts is the limit for the Ultracapacitor. I simply do not pedal fast enough for the voltage to rise that high.

Capacitors are not like batteries. They do not have a "normal" voltage level. Their voltage rises when charging, and lowers when discharging. They can be discharged to 0 volts without harm. All that matters for this configuration is maintaining the voltage below the limit of the inverter and Ultracapacitor. That is accomplished by controlling pedaling speed and effort.

[nomoreheroesanymore]

Inspirational. Thanks so much. Do you have the layout you've described here in schematic form anywhere on the web ?

Maybe you should write a book - be the Hugh Piggott of bicycle power.

Again, thanks for sharing this.

[mjnesbitt]

I updated the Video Info - in the upper right - to include a link to the Circuit Builder application I wrote that can show the circuit for the Power Board - and others as well.

[astronomerroyal]

Many thanks for the video. I have a few Qs.

In a steady state all your Watts Up meters read the same thing, and if they don't then is the difference the net power going into/out of the capacitor?

Also, could you possibly comment on the diode. It must be quite hefty.  The amperage and voltage drop must mean it dissipates quite a bit of power.

I recently built a bicycle generator, the strategy being that I'd charge 12v batteries.

I admire your work. Top class DIY.

[mjnesbitt]

Thanks for the comments!

Yes, the meters show the difference between what is being generated and what is being used, with the difference flowing into or out of the capacitor depending on the direction of the imbalance.

The diodes are 10 Amp Schottky rectifiers: NTE 6083 10A 45V. They have lower voltage drops than Silicon Rectifiers and when I am working hard they become too hot to touch. I plan to experiment with MOSFETs instead of diodes in hopes that their power dissipation will be lower.

[mjnesbitt]

I am assembling a two-generator PPPM that will use a dual 16 Amp Schottky rectifier, and I will use a heatsink on it - or not. See below.

The Schottky diodes cause about a 4-6% power loss due to their natural characteristics. The most direct way to recapture that is to have a switch wired in parallel with the diode, and simply switch the diode in and out of the circuit as needed. I'll have a switch on my handlebars for the dual motor version.

[minicoppergpiscool]

that seems pretty cool it looks like you are ready to charge

how much did the whole thing cost not bike or inverter

[mjnesbitt]

Full retail prices for all parts is about $250 US. If bike parts are scrounged, it can be $100 less.

[minicoppergpiscool]

that is really cool do u charger the capaster and then run things off of it

[mjnesbitt]

Hi, yes I do! The capacitor does not hold as much as a battery but it can run a light for a few minutes or a radio for 30 minutes or so.

Mostly it "smooths out" the power.

[021406407]

you should have been an electrician mate!!!