Aerogenerator questions

[Naptown]

Yep, the average relative wind for a boat under way will be a lot higher than for a moored boat.
Even on a sailboat.

Depends on the direction a sailboat is going in relation to the wind

[inetdog]

It is designed to be used on a yacht where when the boat is under way the wind will trickle charge the house batteries in the yacht.

Yep, the average relative wind for a boat under way will be a lot higher than for a moored boat.
Even on a sailboat.

[ChrisOlson]

Crystal clear, thanks for your comments, will do as you say. And thanks for the info on the contact rating.

I think your turbine will be a lot of fun for you. But I don't know how much energy it will produce for an off-grid system. It is designed to be used on a yacht where when the boat is under way the wind will trickle charge the house batteries in the yacht. We have a 58 foot yacht moored at a marina on Lake Superior and it used to have one of those little turbines on it (except a different brand) but we took it off because it never worked very good. We put 1.5 kW of solar panels on our yacht instead, on top of the pilot house.

The main thing is that a small turbine that size is not a real high energy producer, so I would not expect a lot from it.
--
Chris

[wedgeantilles]

I estimated the Cp at .37. That would be average efficiency for a rotor of the type they use (from what I saw in the photos in the PDF).



Yes, a small NO relay will work fine for stopping your small turbine. I would say a 40 amp would be adequate to handle the inrush when you initially short it without welding the contacts in the relay, even in the strongest wind.

On the regulator, I see no reason at all to bother with one if you are charging a decent sized battery (200ah or larger). The turbine simply cannot produce enough power to ever make it reach absorb voltage so it will basically float charge it (in really strong wind). That being said, a place where the wind blows at 10-12 m/s average is a VERY windy place. I know of only a couple places on earth where it is that windy on a consistent basis, and neither are suitable for human habitation because they are near the poles of the planet. At the more normal average wind speeds on a good wind site of 5-6 m/s I don't think your turbine will produce even 1 amp.
--
Chris

Dear Chris,

Crystal clear, thanks for your comments, will do as you say. And thanks for the info on the contact rating.

All the best,

[inetdog]

Dear Inetdog,

Many thanks, let's try it:

W²

I like to learn as much as I can.

Another thing, sorry for asking this in a thread, but if I want to rate all the comments and answers given by you and the rest, as perfectⁿ where n is far more bigger than one, how do I do it?

See you!

The forum software does not have a mechanism for rating posts in threads. You can reply with a "thumbs up" smiley if you want. But members do not get any additional privileges, status or credibility based on any built-in karma or rating system. I am not sure if this is a conscious choice of the owner or just a limitation of the software used.

But you can increase the usefulness ranking of the whole thread if you want to alert other members to look at it first if when shows up in a search result.

Look at the "Rate this thread" link at the top of each thread.

[ChrisOlson]

Let's give it a try Chris, and will also try to understand how you have estimated a Cp=0,37. Wish I was able to speak with persons like you everyday, just for a few minutes.

I estimated the Cp at .37. That would be average efficiency for a rotor of the type they use (from what I saw in the photos in the PDF).

Another crazy idea I have: if we connect a NO relay contact between positive and negative, just in case one day we have to give the aerogenerator a big brake

Yes, a small NO relay will work fine for stopping your small turbine. I would say a 40 amp would be adequate to handle the inrush when you initially short it without welding the contacts in the relay, even in the strongest wind.

On the regulator, I see no reason at all to bother with one if you are charging a decent sized battery (200ah or larger). The turbine simply cannot produce enough power to ever make it reach absorb voltage so it will basically float charge it (in really strong wind). That being said, a place where the wind blows at 10-12 m/s average is a VERY windy place. I know of only a couple places on earth where it is that windy on a consistent basis, and neither are suitable for human habitation because they are near the poles of the planet. At the more normal average wind speeds on a good wind site of 5-6 m/s I don't think your turbine will produce even 1 amp.
--
Chris

[wedgeantilles]

Aerogenerator questions

You may not have noticed, but the forum software allows you to format superscripts and subscripts (using the X² and X₂ buttons). So you can write " w² " if you want to.

Dear Inetdog,

Many thanks, let's try it:

W²

I like to learn as much as I can.

Another thing, sorry for asking this in a thread, but if I want to rate all the comments and answers given by you and the rest, as perfectⁿ where n is far more bigger than one, how do I do it?

See you!

[wedgeantilles]

Aerogenerator questions

Dear Chris Olson ,

Wow, now I am excited, for sure. This means that we do not have to spend 100 € on a regulator.

So, to keep things simple, I just connect the aerogenerator to the batteries.

Let's give it a try Chris, and will also try to understand how you have estimated a Cp=0,37. Wish I was able to speak with persons like you everyday, just for a few minutes.

Will keep you informed sir!

Another crazy idea I have: if we connect a NO relay contact between positive and negative, just in case one day we have to give the aerogenerator a big brake, is it feasible, or maybe better to connect a big resistor, let's say with your estimate of 230 Watts, in the NO contact? Then use a NC contact from the same relay when things are Ok? This will be far more cheaper than a regulator, and we still have some security.

In our country there is a saying, do not know how to translate it but will try: dress me slowly that I am in a hurry!

All the best!

[ChrisOlson]

If you are concerned about getting the best possible performance out of the turbine, the Midnite Solar Classic is worth considering. It can be customized for the characteristics of a particular wind turbine.

I was able to get the PDF downloaded. Assuming this small turbine is what is shown in the PDF, it is not suitable for a Classic controller. In fact, I question the need for any type of regulator for it all. It is a marine wind charger, designed to trickle charge batteries at 2-3 amps - and it will only produce that at very high wind speeds.

It has a 0.8 meter rotor. So basically even at 13 m/s wind speed and a Cp of .37 it is only going to generate about 230 watts at the shaft, and I think that would be on the high end. With generator efficiency and line losses you're probably around 85 watts @ 13 m/s - not enough to even worry about putting any sort of regulator on it. 85 watts is barely enough power to float a 200ah 24V battery.
--
Chris

[inetdog]

The forces involved are related to w^2, so it's scary...

You may not have noticed, but the forum software allows you to format superscripts and subscripts (using the X² and X₂ buttons). So you can write " w² " if you want to.

[wedgeantilles]

Aerogenerator questions

Dear Inetdog,

Thanks for pointing this out. Some people just do not know about angular speeds, a rotating mass, and a no load situation with wind.

The forces involved are related to w^2, so it's scary...

The xantrex C35 has a feature for diverting the amps to a dummy load when battery is fully charged. My seller is making me a good price for it, so I will go for it.

If we can use the old spinner we will be really proud of him.

All the best,

[inetdog]

Finally I have decided to purchase a C35 xantrex regulator 12/24 Vdc.

No way purchasing the ones in the web page I have found the aerogenerators that are like the old one we have repaired. Too expensive.

Best regards,

Just make sure that the regulator/charge controller that you get has a setting specifically for wind turbine use, since it must be able to drive a diversion load when the batteries are full. Without that the turbine speed could get out of control before any furling mechanism could take effect.

If you are concerned about getting the best possible performance out of the turbine, the Midnite Solar Classic is worth considering. It can be customized for the characteristics of a particular wind turbine.

[wedgeantilles]

Aerogenerator questions

Dear Chris Olson,


Sorry about the coms problems, hope you can see this post.

Attached a PDF file.

The rotor diameter is 800 mm.

The output is DC from the generator, that is like the one shown in the pdf attached.

Regarding the tip speed ratio of the rotor, I am sorry but no clue about that. If I understand you is the relationship between W·R divided by wind speed.

W is the angular speed of the rotor in rad/second, R is the radius of the blade, the product is the linear speed of the tip blade.

Think that the aerogenerator is starting at speeds between 3 m/s and 4 m/s (5,83 Knots and 7,77 knots). It has 6 blades.

No data about W (rad/s) I am sorry. But I am learning from your questions.

Finally I have decided to purchase a C35 xantrex regulator 12/24 Vdc.

No way purchasing the ones in the web page I have found the aerogenerators that are like the old one we have repaired. Too expensive.

Best regards,

[ChrisOlson]

LVM aerogen wind generators.

Thanks - I will look at that as soon as it downloads here. We are on satellite and having problems with our internet this morning.

I am mainly concerned with what the rotor diameter is to figure swept area, what the design tip speed ratio of the rotor is, and whether or not the generator is three-phase AC rectified, or DC with excited field with brushes and commutator. If those things are known I can get a better idea of expected output and what it takes to regulate the output.

(Hopefully can get enough data packets thru this morning to even post this).
--
Chris

[wedgeantilles]

Aerogenerator questions

Dear Chris Olson,

Have no photo yet, but searching in the web, have found a generator that has the same shape and format:

LVM aerogen wind generators.

A link to a brochure: http://www.xylemflowcontrol.com/file...r_brochure.pdf

Will try to find a LVM2SB24 regulator.

If you know some equivalent, please inform.

Thanks all again for all the info provided. This fórum is full of doers and helpers. I like it.