Wind turbine, 3 or 5 blades?

Renewable energies except solar electric or thermal (seeforums dedicated below): wind turbines, energy from the sea, hydraulic and hydroelectricity, biomass, biogas, deep geothermal energy ...
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 17/08/09, 19:21

no, there I am too tired, it will have been a great adventure but above all a hell of a headache.
0 x
User avatar
loop
Grand Econologue
Grand Econologue
posts: 816
Registration: 03/10/07, 06:33
Location: Picardie




by loop » 17/08/09, 22:15

Hi Darwenn

As Alain says, the air gap, that is to say the space between the face of the magnet (ideally cylindrical) and the stator, must be reduced to the maximum. A few tenths of a mm at most.
I would add that your ferrite magnets are rather small compared to the surface represented by a coil.
I would say that 3V at 300 rpm is pretty good.
Be careful though, by reversing 2 wires of the same phase on the rectifier bridge you can lose voltage.
You have to check the different combinations because an error quickly happened.

Good luck
You're almost there

A+
0 x
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 17/08/09, 22:47

3 volts at 300 rpm is too little for me, my propeller does not rotate faster on average with a multiplier of 3. If necessary I can use a multiplier of 7, but it requires more torque so I would like m '' pass and keep the 3.

Yes I thought of a wire error in the phases, I will check that tomorrow. The air gap is however very reduced I even had to do it twice to avoid some friction. As a last resort I will put back a wound rotor as at the origin and drive the alternator at 300 rpm or even 500 max and excite it to see what it looks like with my rewound stator and from what speed it starts up, I will surely put a resistance in series on the excitement. If it is conclusive, let's admit 14 volts at 350 rpm or 500 max with excitement, I will then replace the rotor coil with a neodymium cylindrical magnet as in the previous photo, it will be cleaner and more practical. Finally I will see, I hold on : Cheesy: finally i try.
0 x
Alain G
Econologue expert
Econologue expert
posts: 3044
Registration: 03/10/08, 04:24
x 3




by Alain G » 17/08/09, 23:15

Darwenn

You can use your three separate phases for the triplers used with three capacitors but I doubt that you draw a lot of amps because of the spacing of the rotor / stator.
: Cry:
0 x
User avatar
chatelot16
Econologue expert
Econologue expert
posts: 6960
Registration: 11/11/07, 17:33
Location: Angouleme
x 264




by chatelot16 » 18/08/09, 00:14

put back the other unmodified rotor and pass current in the excitation: you will see that it will make more tension than your too small magnet

well on the power of excitation will be maybe superior to the production of the alternator: it does not matter it is just for a test

then to make the same magnetic induction as the coiled excitation it will be necessary to put much more ferrite than your small magnets

with neodymium it will take less than ferrite but it will still be more expensive
0 x
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 18/08/09, 07:10

Thank you for your answers : Cheesy: I will continue my experiments. Indeed alain, this time I thought of using an alternative tripler, I'll see that. For chatelot, I will no longer use ferrite if I opt for the neodymium cylindrical magnet, and if I am sure of my cost, the investment will be worth it. And finally I have a 220v fan motor with magnet on the stator, I think I will try to make it turn to see what comes out of it with a rectifier and if it works, a 12v transformer at output.
0 x
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 18/08/09, 11:14

Well, I did a test with the fan motor, it is not a magnet, but a cage, so a rotor not powered. Anyway, nothing comes out of it anyway, I don't measure anything as an alternative when I rotate it by hand. There are 4 wires, including 3 for the 3 rotation speeds and 1 neutral and I do not measure anything between the neutral and the speed wires. There is also a 1uf 400v capacitor. So obviously you can't use a 220v fan motor as a generator, it's weird.
0 x
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 18/08/09, 15:04

So there I put the original wound rotor in the stator which I rewound. By training at 2000 rpm without load at once (without excitation) the alternator slows down and I get 115 volts empty !!! houllaaa so I stopped training it at 2000 rpm (it was to see) . Weird that I go up to 110 volts without excitation, the high voltage must create a kind of magnetic field which creates the ignition. In short, I then train by hand at 300 rpm, nothing happens, at 600 either. There while turning at 200 rpm I excite, the alternator starts and hangs, I barely have the measurement time 8 volts before stopping, so we can say that it works at very low speed of rotation, except that the alternator locks as soon as it starts, and there my propeller will lock direct so it is unthinkable. I tried to send that 3 volts to excitement via an external transformer, it works, I have less resistance from blocking but hey it's not the best in this way. So here I am going to put back my magnet rotor because in fact this morning I used neither the regulator, nor the integrated diode bridge so I think that's why I had almost nothing in coil output rectified via a bridge external diode.
0 x
User avatar
chatelot16
Econologue expert
Econologue expert
posts: 6960
Registration: 11/11/07, 17:33
Location: Angouleme
x 264




by chatelot16 » 18/08/09, 15:41

the original wound rotor allows testing the quality of the stator winding

the stator without load must make a tension has can almost proportional to the excitation is time that the magnetic field is lower than the saturation of the iron, that should not take much torque: the couple increases only when one puts a load which pulls current on the stator

the torque increases even when empty when the field of excitation saturates the iron of the stator: this is the case of a normal car alternator which saturates miserably to succeed in charging the battery at minimum engine speed, even if the efficiency is then catastrophic: the engine has enough force not to stall

in your case if it requires a large empty stator torque and far from saturation it is that there is a short circuit in your winding (or coils whose coupling is reversed which contradict each other)
0 x
darwenn
I posted 500 messages!
I posted 500 messages!
posts: 510
Registration: 16/07/09, 17:43
x 9




by darwenn » 18/08/09, 18:01

For the short circuit, everything is ok

or coils whose coupling is reversed which contradict each other


By cons there it is not impossible, I will check this.
0 x

 


  • Similar topics
    Replies
    views
    Last message

Back to "hydraulic, wind, geothermal, marine energy, biogas ..."

Who is online ?

Users browsing this forum : No registered users and 289 guests