开云体育

Hi, my attention got caught by



Amazing, isn't?

Depends on what you mean by economical.? Looking at some of Sam Ben-Yaakov's earlier videos and papers of his grad students in Switched Capacitor Controllers, it seems that 2^n-1 switches would be needed...? Yikes, my calculator says that's more than? 2.028e31 switches.
But I'm no expert
Tim

On Wed, Jul 5, 2023 at 02:36 PM, Tim Hutcheson wrote:

it seems that 2^n-1 switches would be needed

Surely this is not Sam Ben-Yaakov's intention, as he readily describes a natural self-balancing behaviour (propagation indeed) permitting the use of 2 switches per cell in case it is acceptable that the full cells string balancing takes 5 hours. Such a natural self-balancing propagation happens with a 94% efficiency in case of balancing a string of 10 Ah cells, using two inexpensive 125 milliohm 12 VDC mosfets (as switches) per cell, and using one inexpensive 12 VDC 20 microfarad polarized capacitor (as charge exchanger) per cell. Plus a microcontroller (possibly a $0.20 one). But at this moment, I don't know if Sam Ben-Yaakov is talking about a 4-cell string, or a 104-cell string.

Funny thing is, that I filed a patent, way back in about 2007 on balancing ‘energy storage devices’ using a switched-capacitor mechanism…
US 7,994,756 B2

have a fine day, all…

Barry Rowland
Just a simple ?? guy in ??...

I got the impression that the switching mechanism is essentially the same as he describes in a 2008 lecture on SCC, at ?where at about 55 minutes into the slides hew states just that.? So then I looked at the schematic in one of his students thesis for a small implementation and it seemed to confirm this.? I could be wrong.

Tim

Tim wrote, "Yikes, my calculator says that's more than? 2.028e31 switches."

That could be a challenge even in LTspice.

At the end of the day, subcircuits don't make simulations smaller.? If there are 2.028e31 switch subcircuits, they are not represented by one subcircuit that gets 'called' 2.028e31 times.? They have to be expanded into 2.028e31 equivalent circuits that become part of the full netlist.? That's a lot of transistors and more.

I don't think today's PCs are quite capable of that.? ;-)

Andy

OTOH, we don't even need a calculator to compute the MTTF of such a circuit.

-marcel

On Thu, Jul 6, 2023 at 02:22 AM, Lohi Karhu wrote:

Funny thing is, that I filed a patent, way back in about 2007 on balancing ‘energy storage devices’ using a switched-capacitor mechanism…
US 7,994,756 B2

Nokia Corporation, unfortunately no series layout.

On Thu, Jul 6, 2023 at 04:33 AM, Tim Hutcheson wrote:

I got the impression that the switching mechanism is essentially the same as he describes in a 2008 lecture on SCC, at ?where at about 55 minutes into the slides hew states just that.? So then I looked at the schematic in one of his students thesis for a small implementation and it seemed to confirm this.? I could be wrong.

IMO, you are wrong, Tim. The video is about a quasi-continuously varable step-down DC/DC converter.

Concerning his self-adjusting autonomous 4s battery equalizer, Sam Ben-Yaakov described a natural self-balancing behaviour (propagation indeed) permitting the use of 2 switches per cell in case it is acceptable that the 4s cells series-arrangement balancing takes 5 hours.?An LTspice simulation could validate this. Can an LTspice simulation show that a 104s arrangement behaves the same natural way?

It's quite sinple. One must to concentrate on




Regards,
Steph

Then start with the simplest circuit of a single stage, then add stages until it disproves the conjecture.

Tim