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241
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by SparWeb -
I spent more time this weekend working on the design.  I've attached a circuit below.

A few things to know before going in (not really meant for you, BRCM, but others reading this later):
PV panels have a typical Current-V-Voltage curve.  While each PV panel has a slightly different curve, in general they all look the same: flat top, curve, steep slope down.  Where it curves down, I refer to it as the "knee" if the curve.  You've probably heard the term before, but if not, think about how your knee looks... take a look at the example I found.
MicroInverters are designed to convert PV panel DC electricity into AC for the grid, and connect automatically.  This is super-convenient and simple to install, but let's note that they won't convert DC from just any source.  Most if not all of them also are programmed with a Maximum Power-Point Tracking algorithm.  They will adjust the current flowing at any given moment to find the peak power.  If a microinverter was connected directly to a battery, it would not detect a knee of a curve, because batteries do not have a power curve like a solar panel does, and a microinverter would then either run the battery flat or set itself on fire.  Place bets on which fails first.
Wind turbines are built either for connecting to the grid or connecting to batteries.  Generally the battery-connected wind turbines are for off-grid purposes, and require a battery to work.
Batteries are a great part of any RE system, but very rarely can they used as an energy storage for exporting energy to the grid.  Some inverters can do this, but I have found that the conditions needed to allow an advanced hybrid inverter to export energy stored in a battery would make it impossible for the battery to be charged by anything other than that advanced hybrid inverter. Usually people who want their batteries to backup their AC will either use an off-grid inverter or a hybrid inverter but allow no other connections to charge the batteries otherwise.

At this point, it seems like a battery-charging wind turbine is therefore not going to be grid connected.  End of story?

...but what if...

I'm working on a device that can unite the battery to the grid, thus exporting excess energy that would otherwise be spent as heat in the diversion resistors.  It's done via a microinverter, but also controlled to trick the microinverter into thinking it's connected to DC solar panels.

In the circuit diagram, the charge controller, diversion load resistors, micro-inverter, and relay are all common off-the-shelf parts with no modifications.

The Arduino/Feather has several functions.  If you've ever seen an Arduino or a similar micro-board, you have seen you can stack boards together on the same microcontroller board.  For this I'll be putting a "relay board" on top of a "prototyping board" on top of a Feather/Arduino board in a 3-layer stack.  I'm not sure but I may need to do something strange to get the FET's to fit on the prototyping board before stacking the relay board on it...  I haven't built these parts yet so I don't have pictures yet.
243
Forum News & Announcements / Re: Welcome to FieldlinesForum! Your new Community.
Last post by eColumbus -
Hi everyone,

Thank you all for the kind words. It is good to see a lot of familiars faces here.

Bruce, it is fine to tell the whole world about the forum, the more people that know the better.

Once I catch up on a few things I’ll have time to post a few things, and maybe a small project to start with.

Today I had to do electrical work for my wife’s new coffee shop that she got for Christmas. That was one of the worse wiring jobs I’ve ever done. The lamps for the ceiling were tiny LEDs that came with 30 Ga. wires. I hope that she doesn’t get another house next Christmas.

Hey Spar, I see that you were itching to start posting, keep it up Newbie, you need to earn some stars.  ;) 

Ed
244
General Discussion / Re: Hi All
Last post by eColumbus -
Welcome Clockman,

Sure, go ahead and post your files, and if you have something about solar trackers, there is a place for that too.

I wish you happiness and success in your new life in Wales.

Ed
245
General Discussion / Re: AI
Last post by MaryB -
Quote from: Bruce S – on
Here at work, the MUST use the latest Win version that stays updated , unfortunately, is the route we must go since the Dispatch vendor only has their software working with Windows.
The W11 version's AI stuff is so embedded in it we (IT) have to resort to using PowerShell scripts to find and remove them every time an update gets loaded.
In a home-based system, this might not be a big issue for a while, but the CPU and memory hits these hooks starts showing up in speed losses pretty quickly. Our Workstation are no slouches either, even the GPU's though no bleeding edge , are some pretty good ones.
Any unfortunately, none of the WINE based apt's I've tried in Linux distros work well enough to move even the field based tablets over to a good distro.

Cheers
Bruce s

That is what keeps me away from Linux... I have Win only software that fails under any of the emulations I have tried. Some uses direct hardware access and that is where the problem lies...
246
Forum Help & Suggestions / Re: Posting Images
Last post by SparWeb -
Yeah, I already did something wrong.  There was supposed to be an image between the first and second lines of my previous message.  I'm still learning too!
247
Forum Help & Suggestions / Re: Posting Images
Last post by SparWeb -
OK, good, that worked.  In the toolbar above the dialog box the button for inserting the image in-line looks like this:  

Wherever your cursor is in the dialog box, this tool then inserts the code necessary to display the image, which looks like this:
Code: [Select]
[img]https://www.website.com/image.gif[/img]

One more button that seems to be helpful: at the far right of the toolbar above the dialog box is an "eye" that is labeled "view source". Actually what it does is toggles between raw code and a preview of the way it will display after you post it.  Your image should transform from code in square braces to a copy of the image you want to include.

Interestingly, this preview is different from the preview you get above your post when you click the Preview button below the dialog box.  Well, this is the first time I've tried both of these buttons in the same post, so let's see which one takes.  :)

Is anyone confused?  Maybe it's better to just click buttons and try it!
248
Forum Help & Suggestions / Re: Posting Images
Last post by SparWeb -
There is a button above the new post dialog box that says "insert an image" which might be working now. 
I tried it yesterday and the image didn't show up.  I've used it now writing this post, and it might be working.
(I can't be sure until after I click to submit this "Post".)
It should appear right below:
249
Forum Help & Suggestions / Posting Images
Last post by SparWeb -
Please be patient folks, as the new forum gets set up (and the new users get used to it).

we can include images in our posts, when we need to.  To post an image, use the "add files by dragging & dropping or selecting them" at the bottom below the new post dialog box.  This will insert the image at the bottom of your post in thumbnail size.  Users will click on the image to see it full size.

Once things get rolling I would like to see more functions enabled, so that images can be inserted in-line with the text.
250
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by SparWeb -
Quote from: bigrockcandymountain – on
Have your wind turbine charge batteries, like it does right now.  Use a dump load battery charger to spill the excess power, but instead of a resistor bank like we both have, use a grid tie inverter (simple, maybe micro inverter) hooked to the dump load instead.  There would be some confusion of the mppt tracking of the inverter, but otherwise i think it should work. 

LOL
Consider your cobwebs shaken out!  I left just enough tantalizing hints that you picked up on my train of thought, didn't I?  A very similar thing has been on my mind lately.
I have progressed from a basic circuit analysis, to a diagram, and now I'm starting to consider the code I'd need, because I'm going to use a microcontroller as the brains of it.

The Sol-Ark has many inputs: PV, Battery, Generator, and Load.
Actually, Load is bi-directional, meaning it can supply 240VAC back-up loads and it can accept inputs too.  You can even connect your generator to the Load terminals, even though it's got a Gen hook-up right beside it.  Load functions like like it's another grid-tie interface.  It's designed to allow micro-inverters to be hooked up, expanding the possible PV array options connected through the Sol-Ark to include combinations of either or both DC and AC solar panels.

So that got me thinking...
251
General Discussion / Re: AI
Last post by Bruce S -
Here at work, the MUST use the latest Win version that stays updated , unfortunately, is the route we must go since the Dispatch vendor only has their software working with Windows.
The W11 version's AI stuff is so embedded in it we (IT) have to resort to using PowerShell scripts to find and remove them every time an update gets loaded.
In a home-based system, this might not be a big issue for a while, but the CPU and memory hits these hooks starts showing up in speed losses pretty quickly. Our Workstation are no slouches either, even the GPU's though no bleeding edge , are some pretty good ones.
Any unfortunately, none of the WINE based apt's I've tried in Linux distros work well enough to move even the field based tablets over to a good distro.

Cheers
Bruce s
252
3D Printing / 3D printing files
Last post by Bruce S -
In the past year, I've been accumulating files that I send to a friend's 3D printer to test them out.
My purchase of a nice 3D printer as a Birthday Present to me :-), went south when we had to replace the faithful van.
However, I do still have the SRTs and all of them are marked as free by the inventor/maker.
I might try to load them here along with a link to the maker's U-tube account.
He's no longer among the living , but I did get explicit answers from him and later his brother about sharing these, to the affirmative.
I was a one point trying to get him to join as a member to the old forum, but when that started looking shaky I opted to stop bugging him about it.

Since they're up on "thingiverse" I could merely post his user account name so anyone can grab them.

Cheers
Bruce 
253
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by bigrockcandymountain -
I'm feeling like my brain has gone to rot without fieldlines to challenge it.  It's good to read a post that makes me think. 


Here is my feeble attempt at a solution.  It is in no way correct or advisable, but might actually work. 

Have your wind turbine charge batteries, like it does right now.  Use a dump load battery charger to spill the excess power, but instead of a resistor bank like we both have, use a grid tie inverter (simple, maybe micro inverter) hooked to the dump load instead.  There would be some confusion of the mppt tracking of the inverter, but otherwise i think it should work. 

There was a guy (toysforwatts) i think on youtube.  He did a bunch if chinese turbine testing.  He used a small battery and a grid tie inverter (very cheap one)  to export the energy back.  I think it was just battery voltage that triggered the export, and the battery was only big enough to smooth out the surges in power.  It boiled a lot. 
256
General Discussion / Hi All
Last post by ClockmanFr -
Good to see a reboot of Fieldlines.

I do have a few PDF files i would like to post on this forum.
OzInverter book 1st Edition, a selection of Ozinverter 2nd edition chapters, basic Energy creation docs as PDF,s, AC Coupling PDF's. Etc.

The Modern version for DIY of the PLANTE lead acid 2v cell will also be published here. Sadly all the last info on the old Fieldlines forum is probably lost.

My move from France to Wales was completed end of Sept 2025. But how the heck to find all my stuff amongst 400 packing bpxes and tons of machines has been very hard.  Plus building my new workshops, Chem labs and facilties has been very hard. Plus getting my house 12 rooms presentable is also hard work.

I keep finding bits of my good old very large memory and fast systems PC has also been hard, hopefully in 7 days i will be back operational.

I have been working with the Facecloth IFLA group who have been a  very helpfull group of guys and gals.
260
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by SparWeb -
First I have to figure out exactly what I want to do, then out how to do it.
First: What to do:
1) Export energy to the grid?
2) use the AC for other purposes?
3) use the energy for stored heat?

My PV set-up allows me to do both.  When the PV inverter is exporting, it's not going directly to the grid, yet.  It goes to a common bus at the base of my meter, and if the house is using power then the house can be supplied by PV.  This is passive and just the balance of current flows, based on Ohm's law, and it's marvelously simple.  I don't have to distinguish between goals 1 and 2, then.  Goal 3 is much harder, since I put the PV panels on the garage, not the house, meaning storing heat in water or sand doesn't let me heat anything that needs to be heated.

Actually, the excess energy from my wind turbine is being used for heat - just a simple bank of resistors that lose heat to the air in my garage.  Hardly useful but necessary to ensure there's always an electrical load on my wind turbine.
How can the excess energy be better used?
1) feed wind DC to the batteries that back-up the PV inverter?
2) feed the WT's output into a separate grid-tie inverter?
3)

Number (1) is obvious, since my wind turbine is designed charge batteries, and that's exactly how I have it hooked up.  But can the system export to grid the extra wind energy?  No.  The problem with (1) is that inverters simply DON'T export the charge from batteries to the grid - they are designed to do the opposite: store energy from the grid in the batteries. Only when the grid fails do they withdraw energy from the batteries, and then it's only to run the backup circuits.  This mode of operation is familiar to us in uninterruptible power supplies and off-grid power setups.  So as the wind charges the batteries, they get full and the excess wind energy just gets lost as heat.  At least I have a backup power supply that's always ready.

Solution (2) promises to export excess wind energy to the grid, but the options are limited.  Most grid-tie inverters will simply not accept the feed from a wind turbine.  If you tried, you would find that the inverter disconnects the wind turbine's electrical leads from time to time.  A wind turbine running freely will spin its blades very fast - destructively.

To get anywhere with Solution (2) one needs a separate control for the wind turbine.  It has to be independent of any grid-tie inverter to do its safety-related job.  There are such devices on the market and you can get simple ones or fancy ones.  I already have a controller in my WT system, because it's basically an essential safety device, whether the WT is meant to be on-grid or off-grid.  Almost invariably, a diversion load (resistor bank) goes with it.

With that controller in place, does this help choose the grid-tie inverter?  While I mentioned safety, the device that's connected to the grid really should be a UL/CSA/IEEE tested device.  This rules out most of the products you can find, particularly the blue ones on Amazon.  Aurora used to make a fine machine, but sadly they are no longer in business.

There may be options on the market that I haven't noticed yet, though.  If anyone knows of one, please feel welcome to suggest it!