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fillm

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Posted: 06:23am 08 Dec 2011

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Tinker said
I know its nit picking but you came across as someone who knows this stuff and that slip puts a dent in that image

Robert/ Mr Delanco ,

I have read your stuff and I think Tinker is on the ball here , I have noticed that a lot of what you are saying can be misleading and seems to lack depth with most of the technicial detail left out with all roads seeming to lead to youtube hit counts.

What annoys me is some may read and watch your stuff and believe it!!! Sorry if this makes you

MrDelanco said Hello Klaus;

You are not understanding the circuit design correctly.

and the zener diode is only allowing an over-flow of trickle voltage above 2.5 volts to pass and balance the Ultra-capacitor array, any other current is channeled through the ultra-capacitor's and passed down the line. The circuit is operating on one side of the line only.

Hope you didn't burn out too many led's or standard capacitor's.
I am not changing the circuit to make you happy, The circuit works as it is designed. Don't be unhappy.

This circuit diagram was shown as a passive equalization balance circuit for the Ultra-capacitor. With 2.5 volt zener diode's .
[/quote]

Robert , I think it is you who does not understand the circuit properly..

The "zener diode" in the balancers in my system that seem to be identicial to your balancers, is really a silicon diode and the circuit works by passing current continusly over the FVD of the LED and the exceptions would be where there is a high internal loss with in one Ultra Cap in the string . The LEDs are on all the time when the Caps are charged.

Please outline how your circuit is different to this one .

The balance circuit you have used/claimed is HERE and quite clearly states the power consumption for different voltages and how it works.

[quote= ebay sales]
The balancing circuit for a series string of up to 7 ultracapacitors. It basically consists of a silicon diode and a high efficiency red LED across each ultracapacitor. It is designed to leak a very small current from each ultracapacitor. Due to the nonlinear current/voltage relationship of diodes and LEDs, if one or more ultracapacitor is charged to a higher voltage than others, the higher charged ultracaps will discharge significantly faster than the lesser charged ones, thereby tending to equalize the voltages on the ultracaps in the string. As the voltage is reduced, the leakage current diminishes, so at voltages a little below full charge, the leakage is insignificant.
This is the circuit used in my ultracapacitor engine starter/battery booster as seen HERE. Here is the leakage current at various voltages:
2.8V 13.5 mA
2.7V 9.8 mA
2.6V 6.45 mA
2.5V 3.79 mA
2.4V 1.86 mA
2.3V 0.76 mA
2.2V 0.24 mA
2.1V 0.076 mA
2.0V 0.028 mA
[/quote]

MrDelanco said

As the 1st ultra-cap attains full charge of 2.5 - 3.0 volts the zener diode allows the higher voltage to flow through lighting the led and balancing the charging of the 2nd 3rd 4th 5th ultra-cap's and so on down the line.

The led's light when the ultra-cap's is fully charged and the current is moving past them. An ultra-cap will take a fast charge this circuit was designed to move the extra current past the ultra-caps when fully charged and balance the charge in the center of the ultra-cap array. The extra current is channeled right into the charge controller's. Without this balance circuit the ultra-cap array would be in an uneven state of charge. As an ultra-cap's charge is used or drops below the 2.5 volts the led will turn off and build up the charge to balance the voltage in the under charged ultra-cap in the ultra-cap array, this happens very quickly and a visual scan of the panel shows what state of charge the ultra-cap array is in, when a load is being drawn the center section is blinking off and on as the charge in the ultra-cap array is balanced and in a ready state of charge.[/quote]

You may need to do a re-think your explanation here, these balancers can not move large amounts of current past the Ultra Caps .

Balance link The info contained is a about how to make active balancers and is at the bottom after a lot of other good info on how to set them up safely etc.

MrDelanco said An Ultra-cap is not the standard capacitor,[/quote]

Then why do we use the same formular to work out its storage capacity as a standard capacitor?
The energy stored in a capacitor is :
1/2 CV^2 where C is the capacitance in farads and V is volts. The result is in joules, which are the same as watt-seconds. So a 3000 farad capacitor charged to 2.7 volts stores (3000 x 2.7^ 2) /2 =10935 joules. So if you could extract all that energy with no losses, you could run a 1093.5 watt load for 10 seconds.

MrDelanco said
I have posted the information about the ultra-capacitor's.
There is a subsystem not shown before the ultra-capacitor's which regulates and limits the input voltage to the array. This post was about the 2.5 volt ultra-capacitor's ability to enhance a wind system electrical output in low winds.[/quote]

A subsystem , would this just be a "voltage regulator"

I am not sure how you can claim that the ultra caps used in this application can enhance a wind systems electricial output in low wind , to me this is is not the case as these caps are used as storage . If you can please explain how you claim to have found "Enhanced Output", mabe you have found the source of the "Flux Capacitor and have a relationship to DR Emitt Brown"

MrDelanco said There is no limit on the number of cells that can be placed in series to attain higher voltages using a 2.5 volt charge. Ultra-capacitors from Maxwell are rated at 2.5V each.[/quote]

This depends on your system working voltage range as explained below in the Ultra Capacitor bank I fitted to my system , if you have to many it actually reduces the Capacity but will give you a higher safety margin.

So , yes you are correct but...

This is what the person sent me from where I bought my Ultra Caps of Ebay which is also the link I put above to the Balancers , He is very helpful and informative , I can recomend him if any one is thinking of using them .

"Using your systems upper and lower Voltage numbers of 54V, 64V and 21F, the energy is (64^2 *.5 *21)-(54^2 *.5 *21)=14616 joules=1461.6 watts for 10 sec.
But if you use fewer caps (say 25) you get 26F and so 18096 joules. The cap voltage at 64V is 2.56V, so you are safe. You would probably want some kind of balancer in any case since if one cap is leakier than another, it will slowly lose charge, and so be charged to a lower voltage when the string is fully charged, and the others will be higher. If one is much less leaky, it will charge to a higher voltage"

Below is an Ultra Capacitor bank I have fitted to my system mainly because of the High current that is produced buy the wind generators during gusts ( up to 4kW or 80A @ 54V+) and the solar bursts from cloud edge effect ( 45A ) trying to be absorbed by a 225A/Hr Deep cycle battey bank .

There are 25 x 3000F 2.7V Ultra caps which give me a total of 120F @ 67.5V . As my system works between 52V to 64V which the 2 x 1200W grid inverters work at , or I should say the 52V is the disconect V and the 64V is the Regulated Upper voltage set buy the dump loads and Solar Regulation, that then determines the working voltage capacity of the Ultra Cap bank .

So using the caculation ( 1/2 cv^2) to work out what the benifit of these will do to my system is ( .5 x 120 x 64 x 64 = 245760J )-( .5 x 120 x 52 x 52 = 162240J )= 83520J , / 10 = 8300W for 10sec or . /30 = 2784W for 30sec is the storage that the capacitors can absorb on top of the Battery storage. This isn't much when you have large amounts of power being delivered and the inverters do not respond as quickly but fitting the ultra Caps for this purpose is what they are designed for .

By adding more capaciors to this bank will reduce the working storage capacitance but increase the safety margin for no benifit.

This is my Ultra Cap Bank " 25 x 3000 Farad 2.7V " set up and each capacitor electricially isolated from each other as the case is also the Neg terminal , the balancers are fitted .

I fitted these into a purpose built timber cabnet , having them laying arround fully charged with exposed terminals is not a good idea , the power stored in these is lethal.

The finished enclosure .

The bank in place with my existing system , I have set up the 3 way switch to be able to isolate either the batteries or Ultracaps or run on both . The leds started to light up at 43V when charging the Bank and due to some internal leakage a couple are dim compared to the others .

If you want to use capacitors to enhance low wind performance then using them to Ac couple to bridge recs is a good way to get power from low wind , this was extensivly talked about in the "Visual effect of Capacitors" thread by Gordon HERE who basicly came up with the Cap Doubler concept , this is a picture of how my box is set up , the DC then goes directly to the Ultra Cap + & - Bus .

I will cover the benifits the Ultra Capacitors added to my system in smoothing out the wild Voltage spikes from high amperage inputs from the solar and wind in a seperate thread , in no way have I seen any benifit from the ultra caps in low wind or low solar days and would think with the internal losses there would be a parasitic loss . As I have extensive logging on the solar and wind I will be able to show the difference with and with out , but it still all comes back to how quickly the grid inverters can react. Edited by fillm 2011-12-09

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

Tinker

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Posted: 12:56pm 08 Dec 2011

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Hi Phill,
Thanks for your supporting comments, some people seem to get a big kick out of the number of hits to their U-tube video

.

Since you are also located in Australia I wonder if you could pass on the e-bay contact where you got your ultracaps from? A search for these in e-bay got me nothing, maybe I used the wrong search word.
My system is only 24V so about 11 ultracaps would do fine to absorb the instant surge in Amps that I see from time to time coming from my solar tracker.
The deal Maxwell has on their site is just too high to justify getting an ultracap bank as much as I would like to have one. I hope they are cheaper on ebay.

Klaus

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Posted: 01:05pm 08 Dec 2011

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Hi Phil

Nice set up and construction, it is a shame these caps are so expensive. Just a thought are they separated from the battery on the initial charge cycle? It seems to me that they would load the mill excessively until charged.

All the best

Bob

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MrDelanco

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Joined: 12/11/2011
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Posted: 05:00pm 08 Dec 2011

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Hi Phil and Klaus;

Very nice design you added to your system Phil.

I see the similarity in the balance circuit, the ebay one is using a silicon diode and a high efficiency red LED across each ultra-capacitor. I am almost sure I used 2.5 zener diodes with white led's in my circuit but I will pull the cover from the controller tonight and double check it to be sure. If I am wrong I will apologize. The unit was built over a year ago and I have built many other project's in that time.

I didn't intend too mislead and I don't go into depth on the technical detail of the setup it can be confusing to some-others. I try to keep it simple and I don't care about the utube hit's, it was a place to post the video's of the use of recycled items, I didn't setup the utube posting's my Niece did.

I have found benefits in using the ultra-cap's in my system not only to build to a higher charge but to stabilize the output to the storage batteries and inverters allowing for an easy start of heavy loads. It depends on the system setup and how they are used to benefit the circuit design.

You have an impressive setup Phil nice work;
Regards Robert

MrDelanco:Project Videos
It is not only too know what it does but to understand how it does what it does.

fillm

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Posted: 10:06pm 08 Dec 2011

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MrDelanco said
I am almost sure I used 2.5 zener diodes with white led's
[/quote]

It is good to be sure before you start to tell others "they are not understanding"

MrDelanco said

I didn't intend too mislead and I don't go into depth on the technical detail of the setup it can be confusing to some-others.

[/quote]

This is an electronics forum and I would expect people looking and posting here would want to go into some degree of technical detail, especially when your signature says.. "It is not only too know what it does but to understand how it does what it does." then technical detail would be good.

I do not promote myself to be an electronics wiz , but many here past and present know their stuff.

MrDelanco said

I have found benefits in using the ultra-cap's in my system not only to build to a higher charge but to stabilize the output to the storage batteries and inverters allowing for an easy start of heavy loads.

Stablizing the output is defanitely a benifit, but I am not sure about the building to a higher charge?

Klaus.....Here is link to the Ultra Capacitors , you can email him as well, he gives his email at the bottom , he is very helpfull and his service was extreamly good.
I did not see the balance kit listed in his store , it might pay to ask if you want them .

Bob..... I did charge them to match the battery voltage with a variable power supply before switching them into the circuit , I would assume if I did not do that I would have had some usless batteries and melted 16mm cables

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

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Posted: 11:00am 09 Dec 2011

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Hi Phil

How did you equalise the voltage across the whole bank as I do not see that the circuit proposed by Robert would carry enough current to allow equalisation in the short term current draw or charge.

All the best

Bob

Foolin Around

MrDelanco

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Posted: 06:28pm 09 Dec 2011

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Hi Phil;
I opened the controller and lucky I did I found that I need to rewire some parts of the controller using a heavier wire and connecter, some of the connection's showed signs of overheating and replace some power resistor's that are discolored from overheating. I have to investigate and find out why this happen. I read the markings on the diode's and I am using a zener 1N3718 these are old stock unit's and my data sheet list them as 2.2 zener's GPD#3 general purpose diode they were laying around here for year's, leftover's from the old days still have a few more in the bin mixed with some 1N3712's. I checked the voltages in the 1st 6x6 grid (6 row's of 6 ultra-caps) as well as the other grid's and all voltage's in the grid's of the system ultra-cap's are reading correctly.

Regards Robert.

MrDelanco:Project Videos
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fillm

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Posted: 10:05pm 09 Dec 2011

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Hi Bob,

You are right , there is no way in heaven or hell these balancers can carry high current to balance, they are passive balancers and basicly bleed of a small amount current all the time to balance the voltage , I gave a link to the Ebay item on the previous page which explaines the workings .

I will C&P to Here to save going back a page

The balancing circuit for a series string of up to 7 ultracapacitors. It basically consists of a silicon diode and a high efficiency red LED across each ultracapacitor. It is designed to leak a very small current from each ultracapacitor. Due to the nonlinear current/voltage relationship of diodes and LEDs, if one or more ultracapacitor is charged to a higher voltage than others, the higher charged ultracaps will discharge significantly faster than the lesser charged ones, thereby tending to equalize the voltages on the ultracaps in the string. As the voltage is reduced, the leakage current diminishes, so at voltages a little below full charge, the leakage is insignificant.
This is the circuit used in my ultracapacitor engine starter/battery booster as seen HERE. Here is the leakage current at various voltages:
2.8V 13.5 mA
2.7V 9.8 mA
2.6V 6.45 mA
2.5V 3.79 mA
2.4V 1.86 mA
2.3V 0.76 mA
2.2V 0.24 mA
2.1V 0.076 mA
2.0V 0.028 mA

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

Tinker

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Posted: 02:30pm 10 Dec 2011

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Hi Phill,
I just ordered 12 x 3000F/ 2.7V ultracaps, the chap you suggested had a good deal on those.
I'm interested in the balancing circuit you quoted above but the link did not work.
I guess one has to match LED's & silicon diodes to get just the right turn on voltage and minimise leakage below fully charged voltage.

BTW, did you know there's a spelling mistake in your byline

Klaus

Rastus

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Posted: 03:15pm 10 Dec 2011

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Hi Mr Delanco,
You've demonstrated good form under burden of proof,complimented others applications,exspressed a willingness to apologies if needed,reviewed your work and openly disclosed some maintenance issues.I don't feel you could be any fairer and have earned my respect on a personal level.Cheers Rastus

see Rastus graduate advise generously

MrDelanco

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Posted: 07:38pm 10 Dec 2011

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Hello Rastus;
Thankyou for your kind remarks.

Hello: Phil; Klaus; Bob;

I am still trying to diagnose my system. I may have inadvertently created a howland or Cockcroft effect using these 1N3718 diodes in the balance circuit with the ultra-capacitors on the negative side of the system. I researched outside my reference sheets more info about the 1N3718 and found more on the 1N3716 which is a close match in the same group and it can be used not only as a Zener diode and/or a backward diode but also is a tunnel diode. I am monitoring unique swings in the system at lower and higher voltages but the grid array's are staying stable. I don't know what it is as yet but the system is still working though. I think this might be negative resistance bleeding through from another subsystem that is causing the build-up of current in this part of my system but the charge controller is suppose to prevent that from happening and the fact I operate parts of my setup as a positive grounded system and may not be compatible with these store bought controllers. As I stated before I am working parts of my system with the actual flow of the electron from neg-pos not with the conventional flow thought of pos-neg.

The reverse current in the diode my be causing a tunneling, which can take on a form of the Zener effect. The build-up is starting when higher voltage is applied and the current increases on the positive feed into the charge controllers the ultra-caps keep the negative side constant. It looks like a Zener breakdown, it starts at a particular voltage in my system that is 2.5 the limit I have set for the ultra-caps and the voltage remains relatively constant on the scope I see the tunneling start and the readings show normal resistance then I see the reverse voltage drops low and as I increase the voltage the resistance drops and the diode forms a negative flow below the operating current, because current decreases with increasing voltage I don't know where the circuit is bleeding at. I see there is some type of resistance that is causing the build-up of current down the line in my system and the fact I operate this section of my setup as a positive grounded setup makes it a puzzle for now. I am going to make some wire changes to heavier wire and resistor's to see if that will have an effect on my readings.

Any thought's are welcome.
Regards Robert.

MrDelanco:Project Videos
It is not only too know what it does but to understand how it does what it does.

fillm

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Posted: 09:45pm 10 Dec 2011

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Hi Tinker,

I have redone the "BALANCER LINK" .... Let me know if it doesn't work .. or you could email/hlandis@hotmail.com and ask him if he has relisted the balancers as he is more than helpfull. Edited by fillm 2011-12-12

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

Tinker

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Posted: 02:04pm 11 Dec 2011

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Thanks for that link Phill, it worked.
Actually I stumbled onto that yesterday while I was surfing ebay for something. Its just a passive balancer though, Maxwell shows also an active type on their info section which has a much lower leakage. If it could be made cheaply enough and the parts are available I could make a PCB for that.

I did email hlandis@hotmail.com and asked for info in case he also has an active type on his list.

Klaus

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Posted: 10:18pm 11 Dec 2011

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Hi Tinker

Can you post the link for the active equalizer as I can't find it.

All the best

Bob

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fillm

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Posted: 10:10am 12 Dec 2011

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Hi Bob,

Here is the Active Balance Circuits link I posted on the previous page , there is a 10mA and 300mA shown on page 53 / 54 . There are others if you google Ultracapacitor balancing.

The passive balance circuit is easy and cheap but I think it has limitations , I noticed 3 LEDs that had gone very dim and one was out , I checked the volts and the worst was 1V low . I had to do a bit of a manual balance with my variable power supply.

Tinker, if you have found some other links to Active balancers I would be interested to see them as well...Fixed that spelling mistoke

Edited by fillm 2011-12-13

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

yahoo2

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Posted: 12:22pm 12 Dec 2011

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Maxwell ultracapacitor active balance pdf

cell balancing in low duty cycle applications

quote from Maxwell site

When placed in series, a voltage management circuit is often used to keep the voltage of each cell within operating limits. Voltage management circuitry is often used in battery systems as well, however, an ultracapacitor management system need only prevent cells from exceeding their rated voltage. This is typically done with a simple voltage-sensitive current-bypass circuit.

No control is necessary to keep cells above a minimum voltage, since ultracapacitors have no lower voltage limit. For installations that are conservative with respect to individual cell voltage, no management system may be needed. Recent technology improvements have significantly decreased variations in performance from cell to cell, reducing the need for management systems, with the potential to eliminate them completely.

don't know what type of uses this statement is directed at

I'm confused, no wait... maybe I'm not...

Tinker

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Posted: 01:15pm 12 Dec 2011

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Regarding active super cap balancing I got a reply today from hlandis@hotmail.com who says he'd built one but thinks the added complexity is not worth the effort to get a small improvement in leakage. He's doing fine with just LED/diode balancers.

In light what Yahoo2 posted above what I will do once my caps arrive is wire in a rotary switch & multimeter so its simple to check the state of charge of each individual capacitor in my bank of 11.
If there is no worrying variation over some time I might not even bother to fit a balancing indicator.
As I intend to hook up the caps straight to my 24v battery bank they would automatically charge up to the bank voltage. What I want the caps to do is:
1. supply the heavy current peak when the fridges connected to the inverters cycle on.
2. absorb sudden current increases from the solar panels and - when its finally going - the VAWT.

Klaus

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Posted: 02:05pm 12 Dec 2011

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Hi Tinker it sounds like a passive system would be OK for our application provided the caps are matched evenly, so a initial charge to a set voltage say 2.5 and a timed discharge to 2 volts should give a good idea then recharge and let sit for a week and measure the amount of discharge internal leakage, I think that would show up any faulty or out spec item.

I must get a set to fool around with.

All the best

Bob

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fillm

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Posted: 02:36am 13 Dec 2011

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Tinker;Bob,

I have my bank in paralell with a 48V /225Ahr Batt bank , and connected with a slightly higher resistance of 5m of 6mm cable , all other loads and inputs are connected to the U/Cap +&- bus bars .

It only took slightly over a week for 3 caps to become quite out of balance with one at 1v low as previously stated .

The problem that could arise is as caps go out of balance then the others of course are compensating at higher volts which compounds with cycling, if a sudden rise of power is absorbed then it could push the higher Ucaps voltage past their recomended high limit causing damage in a severly out of balance situation .
In lower voltage banks that are closely matched to the upper voltage limit would be more at risk but adding extra caps to increase the safety margin then reduces capacity.

Because of the LEDs different brightness levels I would not have had a visual check to see the problem I had, and I still have not fully investigated whether it is in the balancers or internal leakage.

Tinker , I like your idea with the rotary switch to be able to easily check voltages which would also make it easy to manual equalize if needed, but I would think the need for reliable auto balancing is a must have.

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

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Posted: 03:43am 13 Dec 2011

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Hi Phil

Roberts set up with zener diodes would be one way of monitoring the cell voltage as it wouldn't cut in till the 2.5 volt is across the cell. That would mean that if the led is out the voltage on that cell is low, and when on the brightness of the led would indicate the amount of equalisation taking place, There is quite a range of LED powers available so that could be varied to alter the equalisation current.

Just waffling on trying to get an easy way, as I looked at the active circuit in the manual and it is a bit to complicated and hard to build in the numbers we would need.

I ordered some little 4 F ones to have a play with they are rated 5.5 volts and only $20 for 10.

4 Farad Super Capacitor Electric Double Layer 10 pcs (250939558232) (fleabay)

I was thinking about a very low power float charge system with a separate leg for each cap. It would use a bit of power but most of it is being fed into the cap. A three terminal reg across each cap with a led in series.

Let me know what you think.

All the best

Bob

Foolin Around

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