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Energy/Electricity Storage and Use/Grid Connection => Off-Grid, Batteries & Inverters => Topic started by: woodi on February 19, 2015, 03:54:41 PM



Title: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 19, 2015, 03:54:41 PM
At the moment, I am running 4kw PV, all in little 80w panels that someone was replacing, running into 3 Victron controllers, that feed 500ah @24v of batteries - soon to become 1000ah@24v. A Multiplus 24/3000/70 feeds the house, we keep track of it all online via Victron's VRM datalogging thing, which is a good toy, and all is generally well.
I have got hold of a used Bornay 3000 grid tie wind turbine, that has come with an Aurora inverter, and Bornay controller. I've found a 9m tower for it to go on, and it will replace our old Chinese 400w machine that has run for 3 years charging a set of batts only.
The Bornay kit seems well made - it's a 2 blade machine which I'm not overjoyed about, but it was a good opportunity.
Any thoughts on the best way to integrate and use the power most efficiently?
We have 2 little cottages, our electrical kit is on the end of one of them and I'm doing it up, so now is a good time to think about how best to use the power. We run just about within our means on the PV, but its dicey in the depths of winter up here in the North of Ireland so this should fill in the gaps.
All ideas gratefully received,
cheers
Steve

Here's our PV setup -


(http://s8.postimg.org/texm0oidd/DSCF2982s.jpg) (http://postimg.org/image/texm0oidd/)

inverter and controllers - (AGM batts since replaced with something larger)



(http://s13.postimg.org/jn1lntlmr/photoa_523x700.jpg) (http://postimg.org/image/jn1lntlmr/)

and here's the turbine head, controller and inverter, which I've been looking all over for docs for - its a PVI3600 -



(http://s18.postimg.org/f1kouig7p/photo_1.jpg) (http://postimg.org/image/f1kouig7p/)



(http://s17.postimg.org/9o1ui3qaz/photo_2.jpg) (http://postimg.org/image/9o1ui3qaz/)



(http://s30.postimg.org/d8q1uxc0d/photo_3.jpg) (http://postimg.org/image/d8q1uxc0d/)


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: Ted on February 19, 2015, 04:25:22 PM
So is the turbine the 3-phase 150VAC model which is regulated to 120VDC rather than the 24V or 48V model?  I can't see that you would be able to use the inverter that comes with it if you are completely off-grid and just using PV/batteries at present.

If this is replacing a 400W turbine then your problem will be having too much power!  Get 120VDC immersion for water heating or lots more batteries/dump loads.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: billi on February 19, 2015, 04:35:14 PM
woodi,   how much watt , is the turbine  delivering (max) ?, you can just connect the aurora winturbine GTI  to the AC-out of your Victron multiplus , and (depending on software of the Victron Multiplus )  regulate the windturbine  , to grant no overcharging , or just switch on  an AC heater  automatically controlled by the Victron  at certain Voltage of the battery  (but this depends on the  Windturbine s  output )

Surely a dump load controller idea connected to the battery , to shift all surplus power  away from the battery into a DC heater is another  way

Billi






Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 19, 2015, 05:03:58 PM
Hi Woodi,

you can 'grid tie' your turbine into your own grid created by the Victron using the Aurora no problem. I have done it for years with an 800w hydro turbine designed for grid tying via a Sunny Boy inverter https://lifeattheendoftheroad.wordpress.com/2012/05/15/commissioning-the-powerspout/. I have also just installed a Proven 2.5kW grid tied turbine via a WB6000. Things to be aware of are that you will need some form of regulation to stop your batteries cooking and never to exceed the charging capacity of your inverter. However, be aware that if you do loose your power from the Victron for even a few milliseconds then the Aurora will drop out https://lifeattheendoftheroad.wordpress.com/2015/02/15/a-close-shave/ , I had a 'brown trouser' moment on Sunday by actually flicking the wrong MCB. This could lead to one of two things, the turbine going into 'over speed' and doing damage to itself or more likely frying the inverter due to 'over voltage'.

'AC coupling' a grid tied wind turbine is a great way for 'off gridders' to acquire a quality turbine for a fraction of the cost of a battery charging version. However, it is not for the feint hearted and some kind of safety mechanism needs to be put in place. The Proven turbine is quite happy to 'free spin' so will not come to any harm itself, the inverter on the other hand will if do not switch off the DC quickly enough.

Cheers, Paul


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: Ted on February 19, 2015, 05:17:55 PM
However, be aware that if you do loose your power from the Victron for even a few milliseconds then the Aurora will drop out

Exactly why I wouldn't recommend it.  I don't know enough about this model of turbine to understand its control method and whether such a cut could be fatal for it so far safer not to rely on it.

Even if you do not leave the property for extended periods you still want to be able to sleep soundly on a stormy night knowing that everything is fail-safe.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 19, 2015, 05:22:00 PM
Thanks folks..
Presumably I could program the Multi to open/close the relay at an upper voltage setpoint, and connect to an immersion (or whatever) once the batteries are full, and disconnect once the voltage has dropped for a reasonable length of time? Our Multi acts as the grid here, and everything is wired as normal, so hooking the Aurora in shouldn't be a problem. Is it likely to accept the Multi's AC as being 'the grid' without any extra tweaking, do you reckon?
In theory the turbine is 3000W, and its the 120V version. It  came with a dump load which (I assume), is there in case the grid isn't available? Presumably (if it were running on a proper grid install, in case the grid were to go down?)
Come the summer months, we may have enough from PV, but this being Northern Ireland, we aren't exactly guaranteed blistering heat so I'm not sure what surplus we will have in the longer days. Currently our useage is very much geared to living from the PV, so pretty minimal, but we've 2 cottages to heat - water and space heating if necessary, so I reckon we can find a use for it all. Something we've never had is too much power..


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 19, 2015, 06:55:54 PM
However, be aware that if you do loose your power from the Victron for even a few milliseconds then the Aurora will drop out

Exactly why I wouldn't recommend it.  I don't know enough about this model of turbine to understand its control method and whether such a cut could be fatal for it so far safer not to rely on it.

Even if you do not leave the property for extended periods you still want to be able to sleep soundly on a stormy night knowing that everything is fail-safe.

If you want it 'fail safe' then fit one of these http://www.criticalpowersupplies.co.uk/SMA-Protection-Box-600-With-Load-Resister but not at that price. I've seen them for £350 without the resistor or you could fit a voltage clamp http://scoraigwind.co.uk/2012/01/grid-connected-homebrew-wind-turbines/ Like I said, I've done it for years with a hydro turbine and Heather Hopper with a Proven 6kW. There is absolutely nothing wrong with using grid tied anything with an 'off grid' system, it certainly won't stop me going on holiday or sleeping. I'd be more concerned if I'd an 'off grid' turbine that I had to lower every time it got windy. You have a grid tied Proven yourself Ted, exactly the same criteria apply to that, do you go on holiday?? What happens if YOU have a power cut? Presumably that Bornay of Woodi's was installed professionally and judging by all those capacitors and hardware above the Aurora then it has some voltage clamping device or safety feature in the event of grid failure. From my experience 'off grid' systems are far more reliable than SSE in this part of the world.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 19, 2015, 07:03:24 PM
Thanks folks..
Presumably I could program the Multi to open/close the relay at an upper voltage setpoint, and connect to an immersion (or whatever) once the batteries are full, and disconnect once the voltage has dropped for a reasonable length of time? Our Multi acts as the grid here, and everything is wired as normal, so hooking the Aurora in shouldn't be a problem. Is it likely to accept the Multi's AC as being 'the grid' without any extra tweaking, do you reckon?
In theory the turbine is 3000W, and its the 120V version. It  came with a dump load which (I assume), is there in case the grid isn't available? Presumably (if it were running on a proper grid install, in case the grid were to go down?)
Come the summer months, we may have enough from PV, but this being Northern Ireland, we aren't exactly guaranteed blistering heat so I'm not sure what surplus we will have in the longer days. Currently our useage is very much geared to living from the PV, so pretty minimal, but we've 2 cottages to heat - water and space heating if necessary, so I reckon we can find a use for it all. Something we've never had is too much power..

That should work just fine Woodi, but what happens when the thermostat shuts down  the immersion when the water gets too hot? I'd suggest doing as you say but also fitting a PWM controller in diversion mode, set it slightly higher than EQ voltage.

Cheers, Paul


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 19, 2015, 07:24:49 PM
Ok. I'll also see if I can get some info from Bornay. As the board above the Aurora has 3 phase DC in; AC out and dump connections, I am assuming that it is there to clamp voltage and/or control the turbine with the dump that came with it. The whole lot is in a huge Bornay branded cabinet, and is well installed so I had assumed that the setup would take care of grid failure (or multiplus failure in this case). Can't find any information on tinternet anywhere, which is unusual. Hadn't considered the whole hot water tank getting up to cutoff temp, so thanks for that Camilltech. My failsafes will have to have failsafes. Even the 2m 400w turbine is quite lively when things get out of hand and this is twice the size so I dread to think what it'd be like if it gets away.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: billi on February 19, 2015, 07:54:56 PM
Quote
'AC coupling' a grid tied wind turbine is a great way for 'off gridders' to acquire a quality turbine for a fraction of the cost of a battery charging version.



....   , na , this is not generally true  !

direct Battery charging is  fine and and achieved with a lower budget , surely a MPPT charge -controller  to improve the performance and able to cope with higher voltages to track the turbines voltage down to battery voltage is  more costly , but generally not more costly than 'AC coupling'


Billi



Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 19, 2015, 08:56:37 PM
I got some response from the company. Basically yes if the Aurora stops sensing the grid - whether its the mains grid or one created by the Multiplus then that Bornay circuit and supplied dump load is there for just such occasions and the inverter won't melt, so I can go on holiday and sleep at night :)


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 19, 2015, 09:20:34 PM
I got some response from the company. Basically yes if the Aurora stops sensing the grid - whether its the mains grid or one created by the Multiplus then that Bornay circuit and supplied dump load is there for just such occasions and the inverter won't melt, so I can go on holiday and sleep at night :)

Good news indeed Woodi, I have a 2.5kW Proven and 6.0kW (minus the actual turbine), both were fitted professionally by reputable installers and neither has any protection as regards 'over voltage'  :o I removed both installations from public buildings and can only assume that the installers were looking for another inverter sale in the future  facepalm I've always liked the look of that turbine from Bornay and will be interested to see how you get on. The way I see it, more and more of these grid tied turbines will be appearing on eBay shortly as a result of poor siting and maintenance costs exceeding FIT revenue. No one on the grid wants to buy a second hand turbine they can't claim FIT and a reliable wind turbine makes a perfect winter companion to shed loads of PV. Sure it's a little more complicated than a battery charging turbine but they're much more efficient due to the higher voltage and programmable power curve. I've seen 3.3kW on mine and it starts producing in the lightest of breezes on it's 11m tower.

Good luck, Paul 


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: Billy on February 19, 2015, 10:02:06 PM
Is this another potential "Yorkie" or am I getting mixed up?   ;D


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 19, 2015, 10:03:21 PM
Ah, a bit of a search and I see what you mean. Hopefully not, it shouldn't allow overspeed in theory but easy to test by spinning up the generator and then taking out the multi to see if the Aurora kicks in its own dump load, I would have thought. I imagine the whole thing will be a bit of a  clencher  when it first goes up...


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: billi on February 20, 2015, 05:10:19 AM
Woodi ,  i am only concerned  about , your Victron s inbuilt  charger   being too low in wattage , to cope  with a 3000 watt  rated turbine

Thats why , i would contact Victron , if your Multiplus  can  handle that or is able to communicate with the Aurora GTI and the breaking /dump idea of the turbine .....

Here is a quote  from Victron (from the "solar switch"  leaflet )
Quote
pV power range
The peak PV power (or wind or other renewable power) fed back into the MultiPlus or Quattro should never exceed the maximum charging power.
In case of a MultiPlus 24/3000/70 for example, the maximum charging power is 24V x 70A = 1680W. If the grid inverter “tries” to feed more than 1680W back into the MultiPlus, not all power can be absorbed and the system will shut down.

So , make sure that in case of high wind , that some  power is diverted away from the Victrons internal charger ! (or find out  if your Victron has  communication skills with the Aurora ,...... my old Victrons  would not )

But .....Even if you have a dump  connected  (that works in relation to battery voltage) , that does not mean that your turbine cant achieve 3000 watt at low battery voltage (and therefor no dump connected)  and then  , as written above  .... it could mean trouble

Billi



Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 07:03:07 AM
Quote
'AC coupling' a grid tied wind turbine is a great way for 'off gridders' to acquire a quality turbine for a fraction of the cost of a battery charging version.



....   , na , this is not generally true  !

direct Battery charging is  fine and and achieved with a lower budget , surely a MPPT charge -controller  to improve the performance and able to cope with higher voltages to track the turbines voltage down to battery voltage is  more costly , but generally not more costly than 'AC coupling'


Billi



Direct charging is better but if you can get a complete Proven 2.5kW for £800 then you would be stupid not to 'AC couple' it. My turbine has generated 200kWh in 15 days. My 4.75kW PV around 40kWh. I also bought a complete 6kW (minus head) with 15m tower and WB6000 for £475 you cannot even buy a MPPT controller for that price. There have been two grid tied 6kW Proven's sold on eBlag recently for £4.5k, way out of my price range but they are capable of delivering 100kWh per day in the depths of winter as one 'AC coupled' off gridder will confirm.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 07:06:22 AM
Hi Woodi,

. Things to be aware of are that you will need some form of regulation to stop your batteries cooking and never to exceed the charging capacity of your inverter.

Cheers, Paul


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 20, 2015, 07:47:36 AM
Thanks folks. Not sure how I will get around the rather immovable limit of the Victron's charging capacity, but there is always a way...usually involving more kit, or bigger kit.. :'( Tis too good a turbine not to make use of somehow.
Update - found this from Victron - http://www.victronenergy.com/live/ac_coupling:start
This bit (I think) means that in theory at least I won't see smoke? -
Quote
In both grid-connected and off-grid systems with PV inverters installed on the output of a Multi, Inverter or Quattro, there is a maximum of PV power that can be installed. This limit is called the factor 1.0 rule: 3.000 VA Multi = 3.000 Wp installed solar power. So for a 8.000 VA Quattro the maximum is 8.000 Wp, for two paralleled 8000 VA Quattros the maximum is 16.000 Wp, etcetera.

Since the charger inside a 3000 VA Multi is not 3000 VA but closer to 2000 VA? The explanation lies in the fact that it will regulate . In other words: when there is too much power coming in, causing the charge current to exceed the limit, it will increase the output frequency again and will keep regulating the AC output frequency to charge with the limit.
An example, a 3000 VA Multi, with 3000 W of solar power coming out of a PV inverter:
When the Multi is connected to the grid, all 3000 W can be fed back to the grid through the Multi, no problem.
In case the Multi is not connected to the grid, the 3000 Wp is more than the charger in a Multi 3000 VA can handle. The charger is around 2000 W. Therefore the grid inverter assistant will automatically increase the frequency to reduce the output of the grid inverter, to match maximum charge current.
So my understanding is that the multi would shift the frequency, disconnect the Aurora which would then use its own dump load to prevent the turbine melting.
Or am I just being hopeful?


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 08:10:18 AM
Thanks folks. Not sure how I will get around the rather immovable limit of the Victron's charging capacity, but there is always a way...usually involving more kit, or bigger kit.. :'( Tis too good a turbine not to make use of somehow.

Hi Woodi,

you can always clamp the voltage at the 1300w threshold and divert the rest to heat http://scoraigwind.co.uk/2012/01/grid-connected-homebrew-wind-turbines/

Tis too good a turbine not to make use of somehow.

That's just how I felt about my 2.5 Proven, I already had the 6kW hardware and 15 mast but the 2.5kW was on sale here for weeks and none of the other 'off gridders' were interested. Sometimes you just HAVE to make things work, 'where there's a will there's a way'.

Good luck, Paul



Title: Re: Adding a grid tie turbine to an off grid setup
Post by: billi on February 20, 2015, 08:54:01 AM
Quote
So my understanding is that the multi would shift the frequency, disconnect the Aurora which would then use its own dump load to prevent the turbine melting.
Or am I just being hopeful?

Sounds positive  to me , if your turbine and GTI can shift surplus power on a regular bases ..... and more important that your software in the Victron is able to  control  the GTI (mine wouldnot )


Quote
Direct charging is better but if you can get a complete Proven 2.5kW for £800 then you would be stupid not to 'AC couple' it. My turbine has generated 200kWh in 15 days. My 4.75kW PV around 40kWh. I also bought a complete 6kW (minus head) with 15m tower and WB6000 for £475 you cannot even buy a MPPT controller for that price. There have been two grid tied 6kW Proven's sold on eBlag recently for £4.5k, way out of my price range but they are capable of delivering 100kWh per day in the depths of winter as one 'AC coupled' off gridder will confirm.

Oh , thats good news  to get them second hand....
Paul  , but   close to £30000 for a 6 kw Proven turbine  new ,   excluding  the AC -coupling offgrid inverter and batteries  is , when bought new , quite  an amount of cash  whistle


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 20, 2015, 09:17:04 AM
Yes Billi, it seems Victron have been able to push the newer Multis a bit further with firmware updates. Amazing what you can have them do via software now. I've got ours all hooked out through their Color Control panel to the outside world - https://vrm.victronenergy.com/site/share/3b08d1c1 which gives me something else to tinker with.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 09:20:52 AM



Quote
Direct charging is better but if you can get a complete Proven 2.5kW for £800 then you would be stupid not to 'AC couple' it. My turbine has generated 200kWh in 15 days. My 4.75kW PV around 40kWh. I also bought a complete 6kW (minus head) with 15m tower and WB6000 for £475 you cannot even buy a MPPT controller for that price. There have been two grid tied 6kW Proven's sold on eBlag recently for £4.5k, way out of my price range but they are capable of delivering 100kWh per day in the depths of winter as one 'AC coupled' off gridder will confirm.

Oh , thats good news  to get them second hand....
Paul  , but   close to £30000 for a 6 kw Proven turbine  new ,   excluding  the AC -coupling offgrid inverter and batteries  is , when bought new , quite  an amount of cash  whistle

Aye Billi, but that is what these 'AC coupling' threads are about, finding cheap grid tied turbines and making them work on systems that are already in place.

I say again, in my opinion there will be more and more grid tied wind turbines coming onto the second hand market. These will be turbines put up by local authorities in stupid places to 'satisfy their green credentials'. They will be turbines that work well and the owner now wants to put up a larger one but planning will only allow one. They will be turbines like Michiel's 11kW that are going to be removed because the new owner does not like it. They will be turbines that have to be removed because they are too noisey and turbines that simply do not work because they are in the wrong place.

Over the last twelve months I have seen all manner of grid tied turbines for sale because of the above reasons. People need to be made aware that these turbines CAN work 'off grid' but there are problems. We all know that given the choice DC is better.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 20, 2015, 09:28:00 AM
This might be a stupid question, but if this turbine is rated as having a 120v output, wouldn't it be possible to rectify that and pass it to something like a 150/70 MPPT controller, using voltage switched relay to dump excess? As this came with an Aurora and the control gear I'll use it, but wondered whether there could be an alternative. I know that some of these turbines run at much higher voltages, but the Aurora apparently cuts in at 50v, and the turbine is only 120v according to the specs.....


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 09:55:06 AM
This might be a stupid question, but if this turbine is rated as having a 120v output, wouldn't it be possible to rectify that and pass it to something like a 150/70 MPPT controller, using voltage switched relay to dump excess? As this came with an Aurora and the control gear I'll use it, but wondered whether there could be an alternative. I know that some of these turbines run at much higher voltages, but the Aurora apparently cuts in at 50v, and the turbine is only 120v according to the specs.....

Definitely doable Woodi but when I priced this option for mine which is a 230v turbine the controllers were extortionate. You have to remember it's the the OC voltage you have to worry about. If my OC is over 600v on a 230v turbine then you need to be looking at 300v plus MPPT controllers I guess. I would have been far happier going down that route myself but I never thought of Hugh's idea of clamping the voltage then diverting to heat.

Good luck, Paul


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: biff on February 20, 2015, 10:23:01 AM
Hi Woodi,
              Are you sure that your turbine is rated at 120 before rectifying, ? Perhaps it is meant to power a 120vdc system. If this is the case then there are a decent selection of controller/inverters available, there are even cheaper UPS to be found that will deliver 2.7kw but it sounds very likely that it is 120vdc after rectifying.
  They do 24v and 48v for off grid but say that the 120v is for ongrid?
                                                                      Biff


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: Ted on February 20, 2015, 10:33:08 AM
My understanding is that it is generating 3-phase AC at 150V rectified to 120V DC.


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 20, 2015, 10:34:15 AM
Yes, ish. Though I'm going to stick with AC coupling for now, as it looks like a goer with the kit I have. It was definitely an on grid system, coming with the Aurora box and controller, but I thought it was worth an ask about using the rectified DC. The 120v is just based on the guff on the Bornay literature. They don't seem to publish a lot of stuff about their grid tied version, but then presumably most sensible people just grid tie it and it gets on with the job. It's only when some awkward so and so like me decides to use it like this that the questions arise.
Having talked to everyone about it I am pretty confident that we can do this without killing the turbine, Aurora or Multiplus, as long as there is the right mix of dump loads to deal with any excess. Of course this guarantees that there will be no bloody wind for months after I put it up.....


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 10:41:20 AM
Remember to keep us informed of progress Wood, specially the 'brown trouser' moments, don't be shy  ;D


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: woodi on February 20, 2015, 10:51:52 AM
Fear not, I'm sure there will be many, and I'll do my best to capture as many as possible on camera :) Off to get the turbine head tested on monday, before the fun begins..


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: camillitech on February 20, 2015, 11:11:14 AM
Fear not, I'm sure there will be many, and I'll do my best to capture as many as possible on camera :) Off to get the turbine head tested on monday, before the fun begins..

I'm really looking forward to this Woodi, as I said in a previous topic, I did look at the Bornay so it'll be good to see some pictures of it performing.

Good luck, Paul


Title: Re: Adding a grid tie turbine to an off grid setup
Post by: billi on February 20, 2015, 11:30:24 AM
Yes Billi, it seems Victron have been able to push the newer Multis a bit further with firmware updates. Amazing what you can have them do via software now. I've got ours all hooked out through their Color Control panel to the outside world - https://vrm.victronenergy.com/site/share/3b08d1c1 which gives me something else to tinker with.


Sure ,  if the Victron is upto date ,  and can communicate with the Aurora Wind GTI  and handle the charge current , then surely , like i said , AC coupling  a windturbine  in an off grid PV idea , is beside MPPT controllers , your best choice

Regards
Billi