Anyone grid tied standard wind axial ?

[Dave B]

Simple questions but tough to find specifics. I am asking of anyone who has a current grid tied wind system using the standard axial type alternators built here. What voltage are you using and grid tied inverter make and model ? Where are you located and just in general a few specifics of the grid equipment and code requirements ? 1 KWH meter or 2 etc. It seems like most here are charging batteries or possibly a few hybrid direct heating systems exist. Grid tie with the homebrew axials seems quite rare. Thank you for anyone's information on this.  Dave B

[imsmooth]

Welcome to the party.  If you want to read a lot I have a grid-tie system.  You can read all about it here > http://www.mindchallenger.com/wind

You can either read about the F&P endevours, or you can click on the Axial links and see my current axial grid-tie system.  I would read the whole thing as different and overlapping topics are covered.

I am in New Jersey, USA.  The system will do about 1kw in 20mph winds.  I have not been able to view it in steady, increasing winds, so I am not sure exactly when it furls.  I believe it is somewhere between 25-30mph.  I have seen 1800watts out of it so far.  I have a shunt controller going to a 30R/4kw resistor bank for when the grid goes down.

The axial is 10.5' diameter with hand-carved pine blades.  The generator is modeled after the Homebrew 10' model.  I am using N42 neo magnets.  It is wired with 17g/110turns to give me about 70v @ 100rpm. I set this voltage for the rpm based on the inverter I was going to use.

My inverter is Power-One's Aurora 3.6kw unit.  The voltage range is 50-600v. I installed this myself; it connects to my Mains with a 20A breaker.

I already had solar with the generative metering.  I initially was trying to go through the proper channels with my township, but decided to just do it after a big run-around.  So far no problems.

[bobshau]

I use an Outback GVFX3648 inverter grid connected. The windmill setup is described in this post: http://www.fieldlines.com/story/2009/3/2/171331/4786

Blessings and peace,

Bob

[dlenox]

I have a 17' axial flux wind turbine as well as 720 watts of solar on a tracker.

Am grid tied using Xantrex XW-6048 inverter that is rock solid, to see more I have a website devoted to build/installation/operation here: http://www.briery.com/wind_turbine/

If you have more questions feel free to contact me off line, I'd be glad to help out.

Dan Lenox

[dlenox]

Gee - I guess that I should have read who the original poster was on this topic...  Sorry Dave a bit early in the am for me here...

BTW: I have started up a conversation with MidNite Solar, about their Classic controller. I want to port my software over to use this controller when it becomes available, also want to put it on my turbine...

Dan

[Dave B]

Dan, Bob and Jonathan,

  Thank you for replying to my posting. I am interested in grid tie and it just seems like maybe I'm making it more complicated than it is.

 I have my 16' axial that currently I have wound for 24 volt charging and a DR3624 inverter / charger. Just need to come up with the funds for the battery bank, disconnect and a controller of sorts. Furling starts to limit the output to 3 KW @ approx. 250 RPM right around 25 MPH in a nice constant wind. As we all know it's easy to see peaks much higher in gusty conditions and I've got a few wall ornaments from not having things quite right in the past.

 I like the battery idea but lately I've been distracted by the thought of grid tie. I figured if anyone was doing it this is where to ask. It's all money either way but first I have to educate myself on what's required. Maybe someone else will chime in here also. (Dan, didn't you have your self standing tower up for sale with thoughts of a tilt up ? Thanks again,  Dave B.

[dlenox]

Dave,

You are right, first thing is to see regionally with your utility company what their requirements are, then go from there.

Typically they will require an external grid disconnect so that if they are working in your area they can definatively switch you off the grid.  Beyond that they will probably need to do a walk through with you and perform a full test in which they will see you operating, throw the switch and check that your inverter is not pumping AC out to the grid.

Be prepared to have to 'educate' these utility company guys, as I had to.  They had the preconcieved notion that when they threw the switch to disconnect me that the turbine would stop turning (like a Skystream did).

Obviously with axial flux alternators you better have a good dump load and/or auto-shutdown for your turbine so that when the grid drops out that you are safe. Glen Hurd designed a nice auto-shutdown circuit from his standard dump controller, this keys off the battery voltage and works wonderfully.

In addition I am finishing up some updates for my software so that up to 9 'triggers' can be defined for a software auto-shutdown to occur. This includes wind speed, rpm's, volts, watts, grid dropoff, event duration - and any combination of these variables.  But the software currently only works with Xantrex XW inverters, hopefully soon I can get a MidNite Classic controller - port my software - and use it with my turbine...

I think that Flux previously stated to you that once you are battery charging that your furling may dramatically change.... so be prepared for it.

Dan

[dlenox]

Dave,

Also you may want to look into the net metering laws as implemented in PA, they pretty much tell you all that is necessary for connecting to the grid and they are what the utility will require.

Beyond that the utility company will probably switch out your rotary meter and put in place a digital one that is capable of recording in and out watt/hrs separately, but they should do this at no cost to you.  You however will be responsible for installing the grid disconnect by a master electrician and it will have to be inspected.

Dan

[imsmooth]

My solar system, which was professionally installed, has a DC grid disconnect.  The inverter, which ties into the mains, utilizes 20A breakers as the AC disconnect.  The inverters, as expected, are anti-islanding.

I modeled the wind system in a similar way.  From the turbine I have an 80A switch to short the phases.  The switch goes to a 3-phase disconnect to my rectifier/cap bank.  From there I go a my shunt controller, which is in parallel, which will shunt the power to a resistor bank if the voltage exceeds 234v.  This works whether the grid is up or down; I chose the threshold voltage based on the highest expected value when the grid is running; if the grid is off I will hit this value much sooner.  From the shunt controller I have a DC disconnect to my inverter.  The inverter goes to a 20A breaker which goes to the mains.

I chose the Aurora inverter because it offered the largest input voltage range: 50-600v.  You will, of course, want to stay below the maximum value as this will blow the inverter.  It is UL approved.  There is a company in China by Ginlong.com

It has a slighly larger range, but as of yet is not UL approved.  Both inverters offer over 16 programmable data points for your turbine power curve.

[okwindpower]

I have an Outback 3524 hooked to the grid, going on about 5 years now. I chose the outback for several reasons.  I live in a remote area where storms tends to take down the power lines quite a few times through the year.  With the outback grid ties system, there is a battery bank that is held in the charged state with the voltage being regulated by the inverter when in grid tie mode.  When the power fails, the unit Quickly switches to a regular inverter.  I have a seperate breaker box installed, with 10 circuits going to what I determined to be "necessary" branch circuits in the house and shop.  The switching is lightning fast, and will keep a computer running without skipping a beat, as well as the televsion.  There have been several times that my neighbor called asking if my power was down, and when I checked it was, but I was unaware of it because the D.C. system just kept on running almost everything in my house.

Bob, I have read in detail the build on your 4KW genny, with the wonderful cast coils.  I would really like to get in touch with you and explore the details of your build.  Excellent fabrication and design work.

[dlenox]

Dave,

Another thought today, you. need to immediately contact your utility company to get paperwork started for net-metering grid connection.

This is a package that they will send you with diagrams and such stating how your grid connection should be made, as well as paperwork that you have to complete about your proposed installation, sign it and send back to utility company.

Mine said they needed 60 day leeway, but ultimately it took them about 9 months!!!  I went 'online' sooner than they got themselves organized, but also had a UL listed inverter (Xantrex XW) that was approved for grid connection.

When they came out they saw that I was connected and had the potential to push power back out to the grid, but I remarked to them that they went waaaay past the original 60 days that they stated.

He was ok with it only because I did have a UL approved inverter, if not then they would have cut my connection!  So you have to be careful how much 'pushback' you provide.

That is about all the specifics pertaining to the grid connection that I can think of. Of course you already know that there can be many ways that you implement it, so separate out this from the actual grid connection, begin talking with your utility company to get things in motion and you will do fine.

You have to remember that this consumer net-metering thing is pretty new to the utility companies as well!

Dan Lenox