I am very new to this without much experience in coding or electronics since high school (40 years ago) ~ but I do have my head wrapped well around DC power systems and using other peoples products.
I've built many small wind electric systems in the 500W to 5kW range, mostly for battery charging, mostly for off grid applications. It's easy to charge batteries with solar by simply turning the array on/off as needed to properly charge the battery. Wind turbines are trickier as they always need to be under load, so when the battery is near full only a small bit of power is needed from the turbine, when full of course no power is needed. In the past we'd usually use an off the shelf PWM controller to 'spill' excess power from the battery to prevent overcharging. This works well and allows for proper charging of batteries with a wind turbine.
Almost all of these off grid systems have solar, usually quite a bit ~ the wind usually serves to get through the cloudy days or help through the winter. The wind turbines I build will stop running easily in any wind condition simply by shorting the 3 phase output from the alternator. The idea is to save wear and tear on the turbine, let the solar take care of 'final' topping off of the battery so the the turbine is only allowed to run when the battery can take the full power of the turbine. We never want to overcharge the battery at all. It used to be with flooded lead acid batteries we could overcharge for bits of time but everyone is moving to Lithium batteries where float voltage is lower and overcharging cannot be tolerated.
So I've made up code and a circuit that looks at battery voltage, charging current, and wind speed from a simple anemometer that produces 0-4VDC.
Ardiuno can brake the turbine by sending a signal to an IGBT which will short out the DC output from a 3 phase rectifier to stop the turbine.
4 things can brake the turbine so far.
~ a manual switch
~ ardiuno if battery voltage reaches a certain setpoint, and then release the brake when voltage falls below a lower set point (like... turn on the brake at 54 and leave it on until voltage drops below 50)
~ ardiuno if charging current exceeds a certain setpoint, and then turn the turbine back on after a 'set' waiting period. (in the case that the turbine is for some reason producing too much, perhaps if the wind is very high and it's not furling properly or something) ~ I also would like to display current over the internet.
~ ardiuno if the anemometer indicates very high wind. No sense beating up equipment in rare hurricane type winds. So shut down, stay shut down for a programmed period of time then turn back on/test the waters. I would also like to display wind velocity online.
~ ardiuno, if I want to shut down the turbine for any reason remotely via the internet. (this is a 5th thing I've not figured out yet)
Anyhow, I'm new to it all. I do have it mostly working at this point ~ I don't understand yet how to display information very well or get it online.
My main concern regards reliability. It's one thing to get it working on my bench ~ having confidence it will be reliable on a site may take a while. It should not be exposed to vibration, but on some sites there will be somewhat extreme temperatures (outside in sheds etc). It could be this is all just a good education for me and I should be investing time /money in more expensive hardened equipment for this job, but this platform seems pretty ideal in lots of ways.
I would get commercial charge controller, you don't want to play with big li-ion batteries together with some diy setup for charging, over charge protection and over discharge protection.
Get signal from that controller to arduino to brake turbine when not needed.
To have your setup online, just use some "arduino" with wifi, Esp32 for example. Obviously your board has to be located within your wifi coverage. If not, you need some long range module as well.
This is no different than a solar system still receiving full sun while batteries are at 100%. The MPPT (nobody uses PWM anymore) controller handles the situation.
I noticed you said
float voltage is lower and overcharging cannot be tolerated.
Lithium batteries do not have a meaningful 'float' cycle, in fact doing so is bad practice and degardes the battery life. Overcharging can't happen as the batteries MUST have a BMS and that is one of the functions of the BMS.
As far as looking at data over the internet, my solar system used mostly Victron equipment and I had internet access to ALL the data for up to 6 months.
I think you need to do some more research and reading specifically about how wind is managed by off-grid suppliers. I am not 100% sure if Victron does wind power, but they are the dominant supplier to the boating community, so I would bet they do. Those ships at sea even manage to get their data on the web. Wind power is slowly losing out to hydro power though for sailers since water is MUCH more energy dense than air.
Yes, that's the thing. So far as the wind turbine is concerned we only want to run up to perhaps 90% charge (depending on the battery bank) and let the solar take care of 'topping things off'. Victron really doesnt do anything with wind. PWM is often used with wind to 'spill power' from the battery to heaters (not to turn modulate charging as it would for solar). With regard to MPPT, yes... but, with wind there is almost no good MPPT available except for the Midnite Classic controller, which does work well... but even with that we still must protect the controller from over voltage while keeping the wind turbine properly loaded with requires spilling extra power to heaters with PWM. Up to now we've used a PLC to accomplish some of these things, and I sometimes use aux relays to fire an IGBT that will shut down the turbine. Arduino seems like a nice way to have a little more control.
There isn't a good controller available to do what I want to do. I'm not worried about the IGBT brake in the system, I'm more concerned with the reliability of the ardiuno I guess.
Yes, wind power has mostly lost out to Solar (and hydro where that's available) but it still has its place... but cheap solar has made it such that there's very little innovation in the field. I'm pretty well versed in what's currently available and how folks have dealt with this stuff in the past. Lithium batteries are fairly new, some of these electronics have become cheap and this is a good way to control the type of turbine I'm building. Victron doesn't do much for wind, but I've worked a little with them on a couple systems to at least monitor output. I'm finding myself having to rethink controls on some older systems I put in that used flooded lead acid that were quite a bit more forgiving about momentary abuse from more 'traditional' wind turbine controllers.
If setup correctly and wired carefully considering interferences around, they can be pretty reliable. I would be more concerned about reliability of a DIY li-ion charger/protection.
