Wild DC to clean AC inverter

[nbrooks]

So here is what I am trying to accomplish.  I am trying to take an old Jacobs wind turbine controller that was designed for a grid tie application and make it off grid.  There is a 3 phase "wild" ac input from the turbine that is rectifyed but not clipped by the internal SCR's to variable DC (40-180 volts).  The sensing was designed to tie to the grid and power sync'd to line power and freq then exported or imported depending on demand. 
 
What I would like to do is build a Variable Dc input inverter that will put out a pure sine wave 120/240 vac split phase.  Thus imprinting a usable power out put and allowing the cap/choke inverter to do its part. The design need not handle much power as it is only used as an imprint to regulate the power through the controller.
 
If anyone had any idea on a build for this or a manufacturer that is producing such an item I could really use some ideas.
 
Thanks

[robl]

Whew!

You don't say what kind of experience, skills or tools you have at your disposal, but that is quite an undertaking. Commercially, you can check out the inverters from SMA. Alternatively you can take the more common route and go wild AC>rectified DC>MMPT or PWM charger (with a diversion/clipper circuit component to control overvoltage)> batteries>inverter...

Regards

Rob

[Rob Beckers]

Hi NBrooks,

If you still have the grid-tie controller for the Jacobs you should be able to use it off-grid through "AC coupling". The way battery based inverters work allows most (maybe all) to funnel excess power back from their local grid side to the battery side. This works great for Xantrex and Outback inverters, and likely many more.

The downsides are that the inverter has to be able to handle the full power of the turbine without letting the magic smoke out (so, 3kW turbine, means at least 3kW battery based inverter). The other one is that you loose charge control for the batteries; all excess power gets pushed into the batteries. To avoid overcharging you have to make arrangements so the turbine gets disconnected when the batteries are full. This is usually pretty easy to do, with a contactor and a programmable output on the battery based inverters to switch the contactor off at a specific battery voltage.

-Rob-

[nbrooks]

Hi Guys
Thanks for the help here.  I guess to answer the questions first, I am a master electrician and apprentice instrumentation tech.  I have about 6 (of 13) years working with controls and automation.  So this end is a bit different then what I am use to.  I usually troubleshoot function of electronics and controls, design is something I am just a tinkerer at.  I am familiar with most electronic components and how they "should" operate” but again from a trouble shooting stand point.

Rob
Your thoughts are in parallel to what I was originally thinking with tying the sensing source into the inverter output but here is where I ran into my snag.  When the inverter is in float and absorb charge mode the inverter function is to allow "pass through" voltage and bypasses the inverter all together and just runs off of the non battery source which would end up with the controller sensing its own unregulated power.

……Well I guess your comments have jarred something loose in the hat holder (lol).  Let me know what you think.  I am going to end up with a battery bank here so I could just use a standard 22-24 vdc to 120/240 volt inverter.  I can come right off of my bank and into the controller.  Can't believe I did not come up with this one earlier lol.

[Rob Beckers]

NBrooks, I'm still trying to get the right mental picture of your setup: The "non-battery" source is the grid? So the inverter you're planning to use is hooked up to the batteries as well as the grid, so when the grid is present it's in pass-through?

The Jacobs controller should be fine just sensing grid voltage (and it doesn't care if that's the actual grid or a local 240V source created by the inverter), or am I missing something?

-RoB-

[ChrisOlson]

……Well I guess your comments have jarred something loose in the hat holder (lol).  Let me know what you think.  I am going to end up with a battery bank here so I could just use a standard 22-24 vdc to 120/240 volt inverter.  I can come right off of my bank and into the controller.  Can't believe I did not come up with this one earlier lol.

I don't follow what you're doing at all here.  You got an old UL508 inverter and choke from a 23-10 I assume.  The one with a rotary switch on the front of the panel that rotates from Test to Field Amps to Blade RPM, etc.?

Are you hooking up a Jake for battery charging or trying to use this inverter on a different machine?  If you're hooking up a Jake take that inverter and dispose of it over deep water because that inverter wasn't worth the scrap value of the box.  Then just rectify the output from the generator with regular old rectifiers and tickle the field in the generator with a couple amps of 24 VDC power to get what ever power you want from it.  You just let the turbine run up against the governor and control the power output with the generator field.

If you're trying to use this inverter on a different machine you got a nightmare going.
--
Chris

[nbrooks]

Hi Chris

Looks like you have worked with the UL508 a bit eh.  Let me give you the run down on what I am trying to do and I would appreciate any assistance you can offer.  I have the old Jake set up as you said, a 24 volt magnum inverter and the peripherals with it (gen start, transfer panel....).  I am trying to get a develop a method to take the wild AC from the turbine and make it a usable source of 120/240 that I can put into the line side of my transfer panel.  This will feed the inverter and/or house depending on useage.  Originally I was just going to take the output from the inverter and use that as the field input for the field but because of the "feed through" function of the inverter it would not always be regulated power it would end up using the output from the turbine.

Any suggestions


I don't follow what you're doing at all here.  You got an old UL508 inverter and choke from a 23-10 I assume.  The one with a rotary switch on the front of the panel that rotates from Test to Field Amps to Blade RPM, etc.?

Are you hooking up a Jake for battery charging or trying to use this inverter on a different machine?  If you're hooking up a Jake take that inverter and dispose of it over deep water because that inverter wasn't worth the scrap value of the box.  Then just rectify the output from the generator with regular old rectifiers and tickle the field in the generator with a couple amps of 24 VDC power to get what ever power you want from it.  You just let the turbine run up against the governor and control the power output with the generator field.

If you're trying to use this inverter on a different machine you got a nightmare going.
--
Chris

[ChrisOlson]

Looks like you have worked with the UL508 a bit eh. 

Yes, I have a couple of them laying in my shop.

You are correct in that using the Magnum's output to sync the 23-10's UL508-spec inverter will not work.  You need grid power for that.

I assume you have a early to mid-70's 23-10 with an outbound excited 12-lead Fidelity generator.  Using the wild AC off the generator will be a nightmare because I don't know how you're going to frequency sync it with the line power from your inverter and/or generator.

If you are off-grid I would convert it to battery charging.  Rectify the output from the Jake's generator by building a rectifier panel like any of the guys here with homebrew turbines are using.  The Fidelity's winding is good for ~60 amps per leg and you'll get about 90 amps DC into your battery bank from the rectifiers.  Put a rheostat on your panel and feed the field in the generator with 24VDC power from your battery bank.  Just tickle the field until you get whatever amps you want from it and don't worry about how fast the turbine is running.  Just let it run up against the governor.  Unloaded the 23-10 will start to feather out at 15-18 mph and fully loaded it will feather out at about 25 mph.

That's the simple way.  You won't get anywhere close to 10 kW from it.  But it will deliver 90 amps to your battery bank running up against the governor @ 15-18 mph wind speed with no problem.

Since you have experience with electronics and circuits you could perhaps design a field driver that will regulate the field automatically to match it to wind speed or shut the field off if the wind dies out.

Otherwise I think you're trying to do something that could be done perhaps (anything can be done - all it takes is money), but will require a quite elaborate setup to isolate the output of the turbine to prevent it feeding back onto itself without grid power.  If it tries to island itself it will just fault and the inverter will kick out.  That old UL508-spec inverter needs the grid to have a place to "sink" the output of the generator or it's just gong to see a line fault.
--
Chris

[Rob Beckers]

nbrooks, what's the wild AC voltage range coming of the alternator (assuming proper drive of the field coils)?
If within reason, you could rectify it and drive a Power-One Aurora inverter. Since the turbine has a blade governor that should protect the inverter from overvoltage (the most common reason that I see them get blown). That will let you feed either the grid (line) side or if you choose the inverter side of the Magnum (and do AC-coupling). The Aurora can be programmed to provide the proper load for the turbine so it runs at the proper TSR and is efficient.

-RoB-

[ChrisOlson]

nbrooks, what's the wild AC voltage range coming of the alternator (assuming proper drive of the field coils)?

I'm not nbrooks, nor do I play him on TV.  But the Fidelity generator in the 70's Jake 23-10 delivers up to 180 VAC, the field is 60 ohm, 2 amp, and the output frequency is 40 Hz with the generator running at 1170 rpm (195 rotor rpm).

For nbrooks - I got a 23-10 Jake laying on its side in my shop right now and I'm rebuilding the governor and building a rectifier panel for it for off-grid battery charging.  When I get done with it I can take some pictures of it and show you how I did it, if you're interested in converting that grid-tie Jake to battery charging.  The 23-10 is not the ideal battery charging machine because it can't operate at anywhere near its rated output on a battery charging application.  Plus it's heavy (~2,500 lbs) and you're going to find a whole bunch of other stuff that needs to be done to it if it hasn't been rebuilt recently - the snap ring groove on the mainshaft in the gearbox has to be re-machined for dual rings, the old truck u-joint that drives the generator has to be replaced with a big LoveJoy with a hard rubber spider or you'll be replacing joints every three years, and several other things.

If Rob can help you get it hooked up to an Aurora inverter - that would get more power from it, but the generator on the 23-10 can put out 10 kW pretty easily at 25 mph wind speed and it will hit over 12 kW in higher winds.  So the inverter has to be able to handle it or you'll have blown inverters.  As it was, the UL508-spec inverter that was supplied with the machine was too weak-kneed to handle its output and 23-10's will blow those inverters one right after the other on a good wind site.

If all else fails, email me offline and I'll give you the details of how to convert one to battery charging if it comes to that.  Frankly, if you do decide to go with battery charging, it would be better to sell your 23-10 and buy an old DC Jake Model 25 and rewind the generator for your system voltage.  But it can be done with the 23-10.  And I'm one of these guys that when it comes to wind turbines, if it can be done - I do it   
--
Chris

[Rob Beckers]

If Rob can help you get it hooked up to an Aurora inverter - that would get more power from it, but the generator on the 23-10 can put out 10 kW pretty easily at 25 mph wind speed and it will hit over 12 kW in higher winds.  So the inverter has to be able to handle it or you'll have blown inverters.  As it was, the UL508-spec inverter that was supplied with the machine was too weak-kneed to handle its output and 23-10's will blow those inverters one right after the other on a good wind site.

As long as the blade governor keeps the RPM in check, and therefore the voltage, you can't blow the inverter. Just about the only way to kill an inverter is by going overvoltage, or 600V DC in case of the Aurora inverters from Power-One.

You can go two ways with this: Either one 6kW Aurora, and limit output power to 6.2kW. For higher winds the turbine will simply run to its maximum RPM and stay there (governed). The other option is to stick two 6kW inverters in parallel (requires an isolation transformer, see this link), giving you 12.4kW to the grid. The output voltage of 180V AC translates to roughly 240V DC, or 26A into each inverter at full power. That's within the limits (of 36A DC per inverter).

I can help create an MPPT curve if you need it. You would have to come up with a way to energize the field coils though.

-RoB-

[ChrisOlson]

As long as the blade governor keeps the RPM in check, and therefore the voltage, you can't blow the inverter. Just about the only way to kill an inverter is by going overvoltage, or 600V DC in case of the Aurora inverters from Power-One.

Rob, this is interesting because after I get done with the Jake I'm working on I got another one to do.

So let's say I put an Aurora inverter on it.  Let's say the wind is blowing good at 20-25 mph so the machine is running up against the governor at 195 rpm.  So I start driving the field until the machine is loaded at 180 volts and 35 amps (rectified DC).  I assume the Aurora will handle this.  But now I drive the field to its full 2 amps @ 120 VDC and the machine wants to put out its rated 60 amps @ 180 volts.

If the Aurora won't handle the amps the output voltage of the generator will climb to 220-240.  But there's still more input power than a single Aurora can handle.  So what will the inverter do with this?  Kick out?

It's easy to regulate the power to 6.2 kW by limiting the field.  And MPPT will be tricky with a governed machine because the power output of a Jake is regulated with the field, not by matching the TSR curve of the rotor to generator loading by allowing the voltage to "float" higher than normal.  Even at 15 mph wind speed the machine will be running up against the governor with no load on it.  As soon as you turn the field up the governor flattens the blades out and it goes to work.

I'm just wondering what will happen if I drive the field to max with only one inverter on a 23-10?  And also, does the Aurora inverter need a grid tie to sync it - or will it run standalone and put out 240 split phase, 60 Hz on it's own?  Assuming the inverter will run standalone without a grid-tie, what happens if you have the full 6.2 kW input power but you're off-grid so you only got 3 kW of load for it?  This is one of the problems I've run into with trying to use a machine designed for grid tie in an off-grid application where you do not have the grid to "sink" power when you don't have the loads to use it.
--
Chris

[Rob Beckers]

If the Aurora won't handle the amps the output voltage of the generator will climb to 220-240.  But there's still more input power than a single Aurora can handle.  So what will the inverter do with this?  Kick out?

The inverter doesn't "handle" power; it sets the power level that the turbine gets loaded at based on its MPPT table (which usually means it is based on voltage). If the unloaded voltage of the Jake running full up against the governor is 240V AC that is fine, after rectifying that's still far below the 600V limit. The inverter will output whatever you program it to do, so that would be 6.2kW (the safe maximum for one 6kW inverter) if the Jake is governed.

You will have to take care of driving the field coils though. I don't know if that means running them at a fixed current, or (to save a bit of energy) device some sort of circuit that will drive up the field based on voltage. In the latter case you have to watch out for oscillations caused by changes in load due to the inverter seeing a changing voltage vs. the field coils changing their current.

The inverter has to see a grid to sync to, it won't work stand-alone (battery based inverters are in essence voltage sources, while grid-tie inverters are current sources; the two are very different). However, the Aurora will quite happily sync up with the 'house grid' produced by a battery based inverter. If the battery based inverter is a standard H-bridge design it will move power in both directions; to and from batteries. So the power put on the house grid by the Aurora will flow into the batteries if the local loads are not enough to use it. That works quite well, but it means the battery based inverter has to be able to handle the full power produced by the Aurora, or it'll blow the semiconductor switches in the battery based inverter. That means if your battery based inverter is just 4kW you would have to limit the Aurora to that same maximum power through its MPPT table.

-RoB-

[ChrisOlson]

The inverter doesn't "handle" power; it sets the power level that the turbine gets loaded at based on its MPPT table (which usually means it is based on voltage). If the unloaded voltage of the Jake running full up against the governor is 240V AC that is fine, after rectifying that's still far below the 600V limit.

Well, the inverter has to "handle" power in the form of input current and voltage.  And that's what I'm wondering - what does it do if the input power in kW is more than the inverter can handle, even if the voltage doesn't go over 600.

I don't know what a 23-10 will do running unloaded with the field being driven at full power.  The open voltage might skyrocket past 600.  I don't know of anybody that's tried it and I don't know that it would even be advisable to try it.  The Fidelity generator in the 23-10 is designed to operate at 60 amps @ 180 VAC at full load, with the field being driven at 2 amps @ 120 VDC.

At any rate it sounds like an interesting electrical engineering challenge to get an Aurora inverter to work with a 23-10.  The Jake's UL508 inverter that comes with the 23-10 already has a sort of MPPT scheme built into its electronics, but it does everything based on how it drives the field to match available rotor rpm and power to generator output, matched to the load and inverter output.  The Jake has no need for an MPPT scheme that adjusts the voltage the generator "sees" to track Maximum Power Point.  It does it by adjusting the field to do that, and if you rotate the knob on the front of the panel to the Field Amps position while the turbine is running you can see the field current displayed that the inverter is sending to it - and it constantly varies to keep the turbine running at peak power output for the available wind speed.

I'm guessing that for nbrooks' application, where he needs an off-grid machine, that it's going to be much cheaper to convert the turbine to battery charging.  And he has selected the wrong bank voltage (at 24 VDC) for that because he's only going to get about 2.5 kW continuous out of it on a 24 volt system.  To really take advantage of what the 23-10 can do on battery charging you need a 120 VDC system.  But it all depends on his needs.  The 23-10 will make 32 kWh a day on a 24 volt battery bank @ 12 mph wind speed, which is nothing to scoff at for an off-grid power system.  There's a 23-10 on an island on The Lake of The Woods in Ontario that's been doing that since 1986.  That turbine is on a 120 foot tower, surrounded by open water on all sides for three miles.  When the owner put that turbine in he bought a Lister standby generator.  The turbine ran for 12 years and never once did he have to start his Lister.  One day a big high pressure area settled in and that 23-10 stopped after running steady for 12 years.  When he went to start the Lister to charge his battery bank the engine was stuck and wouldn't turn.  So what I'm saying is that a 23-10 Jake can pretty easily power an entire off-grid home on 24 volt battery charging, even severely de-rated by the 24 volt system.

For off-grid you can make things really difficult, or you can make things simple.  In my experience, making the system simple and basic reliably keeps the lights on.
--
Chris

[Rob Beckers]

The inverter doesn't "handle" power; it sets the power level that the turbine gets loaded at based on its MPPT table (which usually means it is based on voltage). If the unloaded voltage of the Jake running full up against the governor is 240V AC that is fine, after rectifying that's still far below the 600V limit.

Well, the inverter has to "handle" power in the form of input current and voltage.  And that's what I'm wondering - what does it do if the input power in kW is more than the inverter can handle, even if the voltage doesn't go over 600.

No it doesn't.
The inverter sees a voltage XX. Based on that it determines to draw YY Amps. If this is zero Amp the power is zero, if the voltage is 100V DC and it's 2A then the power is 200W etc. The inverter does not 'handle' current, it manipulates the (virtual) resistance that the turbine sees so its input current matches the MPPT profile.

-RoB-

[ChrisOlson]

No it doesn't.
The inverter sees a voltage XX. Based on that it determines to draw YY Amps. If this is zero Amp the power is zero, if the voltage is 100V DC and it's 2A then the power is 200W etc. The inverter does not 'handle' current, it manipulates the (virtual) resistance that the turbine sees so its input current matches the MPPT profile.

Ok, so if I understand how this inverter works - I could drive the field with my battery bank at a set level using a rheostat on the panel to adjust it.  At a set field voltage and current the output of the machine will vary with rpm like a permanent magnet unit.  The inverter will then just look at the voltage and compare that to its MPPT table, and draw whatever amps it wants.  Correct?

Then all you'd need is a cut-out relay to shut the field off if the generator output drops below whatever power it takes to drive the field so you're not wasting power driving the field without getting a return on your islanded "grid".  Then have the cutout relay turn the field back on when the output of the machine rises above the field wattage again.

How much is one of these inverters?
--
Chris

Edit:  More than likely, what I'd do, is drive the generator field with the rectified DC because the voltage would be a lot higher than battery bank voltage.  Then use a cap to smooth the DC so the field power wouldn't pulsate.  The cutout relay would be easy to build using an electromagnetic coil that closes the contacts for the field cutout/cut-in like a DC generator on old cars.  If you had some electronics skills (which I do not) you could even build a regulator circuit to vary the field by measuring the rpm from one of the three-phase legs.  The more rpm you got, the harder you can drive the field.

[Rob Beckers]

Ok, so if I understand how this inverter works - I could drive the field with my battery bank at a set level using a rheostat on the panel to adjust it.  At a set field voltage and current the output of the machine will vary with rpm like a permanent magnet unit.  The inverter will then just look at the voltage and compare that to its MPPT table, and draw whatever amps it wants.  Correct?

Correct.
You have to keep in mind though that you're varying the output voltage when you change that rheostat setting, in in doing so you're in effect changing the MPPT curve for the turbine. That's generally not what you want (might be a good way to experiment though).

Then all you'd need is a cut-out relay to shut the field off if the generator output drops below whatever power it takes to drive the field so you're not wasting power driving the field without getting a return on your islanded "grid".  Then have the cutout relay turn the field back on when the output of the machine rises above the field wattage again.

Is there enough remanent magnetism in the laminates to get output from the generator when it starts spinning (at least some voltage so you can detect it and switch on the field coils)? If so, than this could work.

How much is one of these inverters?

See my business Web site, or eBay (I have some pretty good deals on there). Alternatively, contact me directly (Rob@solacity.com).

Edit:  More than likely, what I'd do, is drive the generator field with the rectified DC because the voltage would be a lot higher than battery bank voltage.  Then use a cap to smooth the DC so the field power wouldn't pulsate.  The cutout relay would be easy to build using an electromagnetic coil that closes the contacts for the field cutout/cut-in like a DC generator on old cars.  If you had some electronics skills (which I do not) you could even build a regulator circuit to vary the field by measuring the rpm from one of the three-phase legs.  The more rpm you got, the harder you can drive the field.

That could work if you build a little current source, so the varying DC voltage doesn't constantly change the field strength of the coils. Only takes a few components, and 600V MOSFets are cheap if all you need is a few Amp (it's been a long time since I designed electronics; I'm sure one of the experts here could quickly draw up a diagram for it).

-RoB-

[ChrisOlson]

Is there enough remanent magnetism in the laminates to get output from the generator when it starts spinning (at least some voltage so you can detect it and switch on the field coils)? If so, than this could work.

Usually, yes.  If the turbine has been parked for a very long time (3-5 years) sometimes you have to flash the field to get them to start.  But otherwise they normally come online by themselves.

This is something I'm going to investigate further.  I got a bunch of other projects going right now, but when I get to this other 23-10 that I'm rebuilding I'm going to check this out further to see if a practical system can be build to drive the field and use an Aurora inverter on it (or a pair of them) for off-grid power.
--
Chris

[nbrooks]

Lets of good ideas here.  I wish I had come across your inverter before I got this magnum.  Yours look like it would have done the trick.  Hindsight being 20/20 lol.  I would like to see what I can come up with without buying a new inverter just yet.  If it comes to that your inverter looks like the way to go.  I was looking at a Bret converter as an option here but the losses are huge do you know any modification that will drop those losses.

Nathan

[nbrooks]

What about using the voltage regulator from a high amp alternator set up.  Do you thing that would work?

[nbrooks]

What about using a voltage regulator from a 3 phase generator to control the field.  I am missing the issue here but the theory seems sound

[ghurd]

I am not the guy who should be responding to this... But,

It is my understanding they would do the opposite of what needs done.
Basically they would limit the output as the available power increased.

Like I said, I don't really know.
G-

[nbrooks]

I was thinking about what you were talking about and it may cause problems under some conditions.  I am going to jot down where I am looking to set this up and maybe we can figure this out.

This is to the best of my understanding so please correct me if you see any errors (anyone)

Line tied system (original design)

The residual magnetism in the field coil starts the builds up of voltage when the turbine begins rotation
The controller senses voltage on the incoming lines and attempts to adjust the field current to produce a voltage that is in limits of the machine.
The ac is clipped by the scr's to a dc wave form then cleaned up and adjusted by a  coil/cap filter set up to match the incoming "line voltage" and freq

My version
The residual magnetism in the field coil starts the builds up of voltage when the turbine begins rotation
The controller senses voltage on the incoming lines and attempts to adjust the field current to produce a voltage that is in limits of the machine.
I leave the field board intact and attached to the controller to avoid the error codes but take the wiring from the field coil and run that off of the output side of a voltage regulator.
The sensing side of the voltage regulator I run from the line side of the controller in parallel with the filter unit in the controller.
The controller does its thing to produce the correct freq as above and drives the field board that is just not doing anything.  The field is run by the voltage regulator.
Now this is where I get a bit fuzzier. 
If there is no draw on the control unit(from batteries, house....) I am thinking that the voltage regulator should act just as it would in a generator and just take the field away until the voltage just drops off to next to nothing to avoid the voltage run away.

My theory on voltage regulators is fairly simple in a watts produces and voltage controlled means the field should affect the current input.
Let me know how far off the mark I am lol
Nathan

[ChrisOlson]

I leave the field board intact and attached to the controller to avoid the error codes but take the wiring from the field coil and run that off of the output side of a voltage regulator.

Nate, you're proposing something I've never tried and I can't even comment on that because my 23-10 is set up for battery charging.  Most three-phase brushless generators have a static or rotary exciter with an AVR and they're designed to operate at 208/240/480 at whatever generator rotor rpm it takes to make 60 Hz.  The Jake's generator will easily develop those voltages but the frequency won't be sync'd.  Using the Jake's choke as you describe, along with leaving the exciter in place might work.  But like a three-phase stationary generator, the exciter is designed to do the exact opposite of what you want, which is limit the field in high winds in the event there's no load.  That's when the Jake goes to full throttle and delivers the big power to grid.

I think it would be simpler to design your own exciter board and drive the exciter field with DC power from a battery, and limit the field current somehow inline with your load, and just let the turbine run up against the governor unloaded.  Then sync it with your islanded "grid" with the choke.  The exciter field is 60 ohm 2 amp.

There's so many variables there to sync one of these machines with a homemade "grid" that it's just about mind blowing, because the machine is designed to have unlimited load up to 20% over its rated 10 kW capacity.  And it hits that (rated power) at only 25 mph wind speed.
--
Chris

[Flux]

I came to this late and haven't read it all but you are asking to take raw power from a turbine and produce stable ac power for your loads.

This presents many challenges. Firstly if the turbine is not producing enough power for the load the thing collapses. If the turbine is producing more power than the load then you have a new problem. With a Jake with pitch control this is a manageable problem, with other turbines it becomes a much bigger issue.

If you can solve these problems then you face the challenge of finding or building the inverter.Normal grid tie uses the grid to clamp the load. Battery based schemes use the battery as a buffer store and regulator, you can then manage things. Wild power is ok for heat where it doesn't matter if it disappears occasionally and it might be ok for power tools and a few other things if you are aware of the problem but I haven't seen a truly successful scheme using raw power with no battery store or grid tie except for heating and for that you don't need a fancy constant voltage, constant frequency inverter, in fact that is far from what you want.

Flux