Pierre's 170W in 1600W out Looped Very impressive Build continued & moderated

[MichelM]

Jeg, onielsen,

Pierre shows in his first video that all the outputs of the diodes converge towards the positive of the bank of capacitors (red wire).
So, if each diode has a utility, what is the good sense of the diodes? Or yes, half is useless.
Luc showed us his video with the flyback diode on an assembly with a single switch, and with a recovery that is discharged into a capacitor.
We need to know how to place the flyback diodes with another device, which has two switches - one underneath, and the other above the coil.
The idea is to put this energy back into the source.
Luc can you also give your opinion?

FR
Pierre montre dans sa première vidéo que toutes les sorties des diodes convergent vers le positif de la banque de condensateurs (fil rouge).
Donc, si chaque diode a une utilité, quelle est le bon sens des diodes ? Ou alors oui, la moitié est inutile.
Luc nous a montré sa vidéo avec la diode flyback sur un montage avec un seul interrupteur, et avec une récupération qui est déchargée dans un condensateur.
Nous avons besoin de savoir comment placer les diodes flyback avec un dispositif autre, qui dispose de deux interrupteurs - l'un en-dessous, et l'autre en dessus de la bobine. L'idée étant de remettre cette énergie dans la source.
Luc pouvez-vous aussi donner votre avis ?

[onielsen]

Hi MichelM,

Pierre's image:
http://overunity.com/17609/170-watts-in-1600-watts-out-looped-very-impressive-build-and-video/dlattach/attach/166918/image//

As the current through an inductor is always continuous (no sudden jumps) this makes the voltage doing the jumps or even changing sign to preserve the value of the current at any given moment. For capacitors the voltage is continuous while the current is discontinuous which is opposite to inductors. When disconnecting a coil the current continues to run through it which makes the voltage across it change sign. The coil changes from receiving energy (sink) to giving off the stored energy (source).

This image is from here: http://zone.ni.com/reference/en-XX/help/370736U-01/ni_dc_power_supplies_help/sinking_sourcing/

Looking at Pierre's image the left hand side coil has the current going to the right when the top left and the center bottom switches are closed. The coil sinks power and stores it as magnetic energy. If opening one of the switches the current through the coil continues running but the voltage across the coil changes sign. The coil is now a source and gives off the stored magnetic energy. The voltage across it immediately adjusts to fit the current running. If the impedance the coil sees is high the insulation breaks down or a spark forms across the switch opening or the coil has enough capacitance between the winding to store the magnetic energy as electric energy.

Putting diodes to the supply rails prevents the destructive flyback voltages. The current instead takes the path through the diodes. The diode from the right hand side of the coil lets the current go to the positive supply rail. A diode from the negative supply rail across the bottom switch of the negative hand side is needed to close the circuit if the bottom switch is opened.

Regards
Ole

[Jeg]

L192
The maximum current that arduino 2560 can give across its outputs is 200mA in total. That means 200/30=7mA max per pin output. I tried to find how much current L298 board needs at its input but no luck. What do you think? Will arduino be able to drive 30 of such boards?

[pmgr]

L192
The maximum current that arduino 2560 can give across its outputs is 200mA in total. That means 200/30=7mA max per pin output. I tried to find how much current L298 board needs at its input but no luck. What do you think? Will arduino be able to drive 30 of such boards?

Hi Jeg, that should not be a problem. The inputs to the L298 board are digital CMOS/TTL compatible inputs so they consume no current, typically 10-30uA per input, see the datasheet:
https://www.sparkfun.com/datasheets/Robotics/L298_H_Bridge.pdf
PmgR

[seaad]

A 12 step simulation at 5Hz.