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4 Kwatt wind generator


Erastus
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Who would be interested in a wind generator of 4Kw.

I am thinking of getting all done via a lazer cutter and then molds for fiber glass blades.

If you are interested leave a comment or a yes please will see to what level I can get it in a kit form with direct orders from suppliers.

It will have a MPPT look alike interface to work with a standard inverter and in my case I will have it working on grid tied system....

I am also planning to have a micro to do the feathering so we can control the speed and temperature

If this is boring then delete the subject.

Edited by Erastus
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1.  What do you expect dimensions?

2. Why MPPT instead of PWM control?  And does this need feathering? (considerable increased cost).

3. What do you expect the final price to be ?

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On 2021/01/26 at 6:22 PM, Adri said:

1.  What do you expect dimensions?

2. Why MPPT instead of PWM control?  And does this need feathering? (considerable increased cost).

3. What do you expect the final price to be ?

MPPT is for me a useless electronic device. It has losses and you pay a lot of money to generate loss and software is more flexible than a MPPT.

The way I am laying out the stater system and the control of the system I recon I will get away without feathering. 


A friend of mine is currently busy doing the mold for the blades and the  length is 1870mm.

I bought plans for the blade and once done hopefully replication will be a lot less work as I am the worst one when I have to saw cut and what ever.

The  blade I would like to make from fiberglass and aluminum instead of wood.
Once we have the blades and shaft that will determine the final length as I will mount it on a shaft with bearings so that I can feather it electronically by turning the blade. Feathering is easy and lets say its a more or less same concept as a chopper sets of blades just a lot more basic.

I have already sourced a local magnet supplier and I will use 70mm x 20mm x 12 mm Ferrite magnets. I am aiming at 128 magnets R54 each in stead of R128 each

12Kg copper wire @ R250 per 500Gram

Not sure what the costs of the electronics will be as I do it slightly differently.  Software is a cheap cheat I recon with a small control loop and a few Ct's and  R300 Mosfets CPU board R430 that will have a very good controller and will also control the feathering if my manage system is not good enough.

 In my case I want to use the same inverter that I use with solar.  Time will tell if I need a dedicated inverter.

I hope that the first one costs less than R15K  and then will source from China  as copper and magnets is 1/3 the cost compared to local suppliers.

I recon instead of having expensive batteries this will be more use full in the Cape Winters and windy nights.

My absolute main concern is the temperature of the stater windings.  4Kw is a lot of heat to get rid off.  I recon that is going to be my challenge to force wind in for cooling.

The dimensions will be as per the national rules.

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Cool, i know of a old electrical engineer that builds his own high quality stuff. Pm me and i will send you his contact details. 1. PWM is the only way, unless you go for the Midnight. A break is a must, best is to tie the tail like the old wind mills did. my recommendation would be to first build the turbine and sort out all the kinks, and just purchase a controller for now.

 

a lot or r&d goes into doing it right. Fiberglass is cheap but does not last. Carbon fire is the way to go. speak to Jason, he imports blades from the USA

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On 2021/01/29 at 8:44 AM, Wildebees said:

Cool, i know of a old electrical engineer that builds his own high quality stuff. Pm me and i will send you his contact details. 1. PWM is the only way, unless you go for the Midnight. A break is a must, best is to tie the tail like the old wind mills did. my recommendation would be to first build the turbine and sort out all the kinks, and just purchase a controller for now.

 

a lot or r&d goes into doing it right. Fiberglass is cheap but does not last. Carbon fire is the way to go. speak to Jason, he imports blades from the USA

Thanks been designing my electronics for many years but love chatting to people.
Who is Jason?
I bought a plan for the blade that "fits" a 4Kw generator. 

I am terrible with wood work a good friend of mine busy with the blade according to the plan so I can get it made from Carbon Fiber

 

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On 2021/01/29 at 8:44 AM, Wildebees said:

Cool, i know of a old electrical engineer that builds his own high quality stuff. Pm me and i will send you his contact details. 1. PWM is the only way, unless you go for the Midnight. A break is a must, best is to tie the tail like the old wind mills did. my recommendation would be to first build the turbine and sort out all the kinks, and just purchase a controller for now.

 

a lot or r&d goes into doing it right. Fiberglass is cheap but does not last. Carbon fire is the way to go. speak to Jason, he imports blades from the USA

The controller is the easy part. It's dumb software with a cheat.

The trick will be the direct coupling "into" the inverter.

The ultimate goal is to feather the blade to achieve constant RPM in gusts.

For that I am looking at CF so I can mount it on aluminum  connected to a drive.
 

 

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  • 2 weeks later...

Getting a little closer with cost:

 

Magnets                                           R 3726
Copper                                             R 4654
A Carbon Fiber Blade  R 830 x 3   R  2490
Steel                                                 R  1830

Seems that the 3 - 5Kw wind generators cost will be   R 12 700. Cheaper than I thought it would be.  I am pretty sure for a few bob extra it will have feathering as part of the design.  The blade was designed by professionals and I bought the  foil pattern. The blade "mounting side" will be manufactured from aluminum and not wood.

Chances are good that in the stronger winds in Cape Town I should get closer to 6Kw.  That needs to be tested and verified.

 

 

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2 hours ago, Erastus said:

Getting a little closer with cost:

 

Magnets                                           R 3726
Copper                                             R 4654
A Carbon Fiber Blade  R 830 x 3   R  2490
Steel                                                 R  1830

Seems that the 3 - 5Kw wind generators cost will be   R 12 700. Cheaper than I thought it would be.  I am pretty sure for a few bob extra it will have feathering as part of the design.  The blade was designed by professionals and I bought the  foil pattern. The blade "mounting side" will be manufactured from aluminum and not wood.

Chances are good that in the stronger winds in Cape Town I should get closer to 6Kw.  That needs to be tested and verified.

 

 

You can mount it on my roof in Somerset West to test the winds. 😜

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14 hours ago, Achmat said:

You can mount it on my roof in Somerset West to test the winds. 😜

When mine is working the way I want it to be. There will be a mold and all metal cuttings available at Schuurman engineering at cost. You are more than welcome to get the stuff at cost.

That's what its all about.

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Interresting topic building one's own turbine. 

Some questions 

Which parts will Rotate? The coils or the magnets on the Stator?

How will you transfer power from the turbine? 

Do you intend on generating 230 VAC? Or are you converting 3phase AC to DC and then back to 230 VAC

I see you mentioned a MPPT how fast does the MPPT you intend on using Sample voltage Changes?Considering wind power can be erratic.

Will you use buck and boost controllers?

Do you intend on Electro Mechanical braking system or mechanical.

Will your turbine auto furl?

Are you mounting it on a pole? If so what solutions do you have for urban height restrictions?

Have you got Municipal permission to install a turbine?

What safety features will your Turbine have?

What will the air gap be between the magnets and the coils?

What types of bearings will you use?

Did you factor in frictional losses?

Is it direct drive or are you using pulleys or reduction gears?

Will the turbine follow the wind IE does it have a tail like a windpump?

What mechanism are you using to prevent over speeding or revving?

How did you calculate that the blades will produce 4KW?

At what Rpm will your turbine generate 4KW?

What cable thickness will you use?

How Many Blades will your Turbine Have?

How do you intend on balancing your blades?

Just a few silly questions I know but I am Curious..

 

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Posted (edited)
On 2021/02/28 at 3:38 PM, Boerseun said:

Interresting topic building one's own turbine. 

Some questions 

Which parts will Rotate? The coils or the magnets on the Stator?

How will you transfer power from the turbine? 

Do you intend on generating 230 VAC? Or are you converting 3phase AC to DC and then back to 230 VAC

I see you mentioned a MPPT how fast does the MPPT you intend on using Sample voltage Changes?Considering wind power can be erratic.

Will you use buck and boost controllers?

Do you intend on Electro Mechanical braking system or mechanical.

Will your turbine auto furl?

Are you mounting it on a pole? If so what solutions do you have for urban height restrictions?

Have you got Municipal permission to install a turbine?

What safety features will your Turbine have?

What will the air gap be between the magnets and the coils?

What types of bearings will you use?

Did you factor in frictional losses?

Is it direct drive or are you using pulleys or reduction gears?

Will the turbine follow the wind IE does it have a tail like a windpump?

What mechanism are you using to prevent over speeding or revving?

How did you calculate that the blades will produce 4KW?

At what Rpm will your turbine generate 4KW?

What cable thickness will you use?

How Many Blades will your Turbine Have?

How do you intend on balancing your blades?

Just a few silly questions I know but I am Curious..
 

 

Rotate: Magnets will rotate the I need no slip rings
Voltage:  Not 3 phase but something I plan to manipulate with software. So the voltage I am not sure what its going to be as I want to use it for a break system as well. Once I get it working I will discuss that a bit more. I am a little nervous to the idea but I recon after understanding the flux system I recon I can manage it with a bit of software cheat  to generate and break.
WindPower:    The micro I am using does 2.5M steps per second so that is the least of my worries as the sample rate will be in .1milli second. I am doing my best not to use an MPPT.
BuckBoost:  If my design works right no buck or boost  converters
ElectroMechanical :   Nope
Furl:  The first model I will have a motor controlling the angle of the blades under micro processor controles. Once my software working properly then I will dump the feathering as I believe software will control it properly
Gap: 21mm
Bearings:   NTC they are very important so will refrain from Chinese stuff.  I had some failures with Chinese stuff on my solar tracker.
Losses:  The only losses will be in the inverter and the effectiveness of the blades.
Follw:    Yes it will follow the wind with direction monitor and RPM monitor plus Kw so I can display it live on a web site


 


 

Edited by Erastus
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I saved to early sorry:

Rotate: Magnets will rotate the I need no slip rings
Voltage:  Not 3 phase but something I plan to manipulate with software. So the voltage I am not sure what its going to be as I want to use it for a break system as well. Once I get it working I will discuss that a bit more. I am a little nervous to the idea but I recon after understanding the flux system I recon I can manage it with a bit of software cheat  to generate and break.
WindPower:    The micro I am using does 2.5M steps per second so that is the least of my worries as the sample rate will be in .1milli second. I am doing my best not to use an MPPT.
BuckBoost:  If my design works right no buck or boost  converters
ElectroMechanical :   Nope
Furl:  The first model I will have a motor controlling the angle of the blades under micro processor control's. Once my software working properly then I will dump the feathering as I believe software will control it properly
Gap: 21mm
Bearings:   NTC they are very important so will refrain from Chinese stuff.  I had some failures with Chinese stuff on my solar tracker.
Losses:  The only losses will be in the inverter and the effectiveness of the blades.
Follow:    Yes it will follow the wind with direction monitor and RPM monitor plus Kw so I can display it live on a web site
Pulleys:  No pulleys or gears
OverRpm:  Prevention via software loop
Blades:  Blades are very tricky so I bought a design from a firm that designs blades
RPM/Kwr:  If my calculations are correct +/- 420 Rpm
Cable:   6 mm
3 Blades:   The blades neck will be machined from aluminum If I can I would like to step it up to 5 blades.  Time will tell.
Blades Bal:  A friend made the blade for me from supa wood.  Its been sealed and painted will get it tomorrow.  The painting was done to prevent stickiness as much as possible.  I will now make a mold for carbon fiber. I am speculating but a single blade will weigh +/-  600G as the carbon is +/- 300G.  The method used with the mold and machined al will have a very uniformed weight The crucial factors will be the start of the blade from the center shaft, then the length and then the weight of the carbon and fusion epoxy.  What I been told the weight will be very close as its from a mold made and design for carbon-fiber.  The idea with this is to weigh the metal make sure each part has the exact same weight and then the carbon before molding it together.  Then the delta should be easy to manage. The inside on the blade instead of wood will be solid aluminum and that will add a bit of weight but still much lighter than the fiberglass or wood blades.  The carbon fiber will have an extra 1mm stainless multi core cable that will be tied to the main connection.  Like a F1 car  wheels.  If I  can manage this then it will be easy to replicate for any person who would be interested to make use of it.  The only prob the system will not be available without the controller as per my version else any one can make up their own stater.  Its simple the software will manage the device and send info back to my data base for analyses.
The blades how ever will be available and so the mold. The intention is not to make money but so we all can have nice stuff at avoidable prices and ...
My device use 23Kg of copper so you can understand its a little heavy but then in strong winds which we get very often I hope to push 6 and if I am very lucky 7Kw.  7 is a dream!!!! 6 not so far fetched.

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The National law allows for wind turbines:
48 Use of the property
The following use restrictions apply to property in this zoning:
(a) Primary uses are institution, hospital, place of instruction, place of worship, place of assembly, rooftop base telecommunication station, filming and open space.
(b) Consent uses are boarding house, conference facility, cemetery, crematorium, funeral parlour, freestanding base telecommunication station, wind turbine infrastructure, veterinary practice and urban agriculture.
[Item. 48 substituted by s. 39 of City of Cape Town: Municipal Planning Amendment

Once it is national a local law can not over rule it (Constitution) and if it is a restriction it must be registered on your title deed  or traceable via title deed else you have the right with out asking the council.. I must check this but I am pretty sure that a wind generator mounting point can not be higher than 3 M from where it is mounted. Mounting not total height

 

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8 hours ago, Erastus said:

Blades Bal:  A friend made the blade for me from supa wood.  Its been sealed and painted will get it tomorrow.  The painting was done to prevent stickiness as much as possible.  I will now make a mold for carbon fiber. I am speculating but a single blade will weigh +/-  600G as the carbon is +/- 300G.  The method used with the mold and machined al will have a very uniformed weight The crucial factors will be the start of the blade from the center shaft, then the length and then the weight of the carbon and fusion epoxy.  What I been told the weight will be very close as its from a mold made and design for carbon-fiber.  The idea with this is to weigh the metal make sure each part has the exact same weight and then the carbon before molding it together.  Then the delta should be easy to manage. The inside on the blade instead of wood will be solid aluminum and that will add a bit of weight but still much lighter than the fiberglass or wood blades.  The carbon fiber will have an extra 1mm stainless multi core cable that will be tied to the main connection.  Like a F1 car  wheels.  If I  can manage this then it will be easy to replicate for any person who would be interested to make use of it.  The only prob the system will not be available without the controller as per my version else any one can make up their own stater.  Its simple the software will manage the device and send info back to my data base for analyses.
The blades how ever will be available and so the mold. The intention is not to make money but so we all can have nice stuff at avoidable prices and ...
My device use 23Kg of copper so you can understand its a little heavy but then in strong winds which we get very often I hope to push 6 and if I am very lucky 7Kw.  7 is a dream!!!! 6 not so far fetched.

This line should read:  If I can manage this the blades will be easy to replicate and each person can make their own blades, then a rotor and alternator to a standard form to eliminate the use of my controller.  Then RPM can be managed by off setting the tail. Once my stuff working properly it will be available for those who want to use it.

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