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diy solar

Cheap chinese horizontal wind turbine, an in depth exploration.

brandnewb

Going for serious. starting as newb
Joined
Oct 6, 2021
Messages
2,200
Location
-5m altitude from sea level
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Please do not reference to unproven products. A proven product should at least have an rpm vs some kind of output graph with warranties.

for the building of a DIY alternator that actually works please see
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I recently received my very first wind turbine from, wait for it.. you've guessed it! ;)
https://www.aliexpress.com/item/4000707176751.html
I ordered the 48 volts version.

Images below

Now I do not expect the advertised 6000watts of power generation potential and even the seller admitted only to expect 4000watts which I still do not believe.

I did not order any extra components yet as I first want to test what it can generate as my location is ideal for high wind loads even though in an urban area.

Now how can I test what the 3 phase AC generator is generating in terms of watt, amp, volts and the likes (please forgive me if I include units here that are not relevant in this stage as I am a total newb)

There are 3 wires available (I am assuming one for each of the 3 phases) where I can connect something while it is spinning to see what, if any, flows over the wire.

Could anyone please advice me on how to proceed? what tool to buy to be able to test the power generation on each of the phases.

generator from top.jpg

generator from side.jpeg

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TL;DR Update

Current verdict = Don't do it!!!
The blades need to spin far too fast for the alternator to generate any useful output. That is not safe.
I am considering a vertical turbine at the moment knowing full well the efficiency will be even less that a horizontal one like this but I believe they are less dangerous.

winding resistance (kilo Ohm)​
leads​
a​
b​
44.1​
c​
b​
49.5​
a​
c​
49.5​
Rpm +- 315​
no load​
Alternating Current, measured with the Aac at 200m setting​
leads​
a​
b​
5.6​
c​
b​
5.1​
a​
c​
5.5​
Vac​
leads​
a​
b​
26.2​
c​
b​
24.3​
a​
c​
26​
Vdc​
34.3​
Direct Current, measured with the Adc at 200m setting​
8.3​

alternator output with 3 phase full bridge rectifier attached;

with load (details below)
rpm: +- 820 (my poor drill has difficulties)
Vdc: 2.45
Adc: 1.65

The load details (light bulb)
resistance = 2.5
12V
55W

Results at +- 320 rpm and 4 x 12v5w bulb in series (48v 20w load if not mistaken)

additional info and photo's of dissasembled alternator

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I did not order a controller yet, I did not want to potentially waste more money than needed. I'd like to first test it out and perhaps order a controller from a reputable source.

I do have a fluke multi meter

is there some kind of load (I have a 3 phase electrical heater for example ) I can connect to the 3 wires and use the fluke to measure volts, amps on the 3 wires separately?
 
I did not order a controller yet, I did not want to potentially waste more money than needed. I'd like to first test it out and perhaps order a controller from a reputable source.

I do have a fluke multi meter

is there some kind of load (I have a 3 phase electrical heater for example ) I can connect to the 3 wires and use the fluke to measure volts, amps on the 3 wires separately?

Well, you can measure volts (AC) across any of the wires while spinning it with a drill. That will tell you if they connected up the wires inside.
As for amps, connect a 12v car tail light (non LED) across any of the 2 wires and spin it with a drill (start slow). If it lights up, then you have amps.

As for how you can tell if it puts out it's rated power, that is hard to do without the controller.
 
for measuring AC volts, the wires do not have to be connected to a load? As in I just leave them unconnected and put my mmeter around one of the wires while the turbine spins?

for amps, did you mean connect a 12 volt car tail light to any 2 of the 3 phase wires?
 
Leave them unconnected and measure AC volts.
Correct on the amps.

Test between several different combination of wires. So between wires 1 and 2, then 2 and 3, then 3 and 1. Assuming it's spinning the same speed each time, the voltages and the light should light up the same.
 
it spun crazy fast, without a load, in the current wind we are having. The blades even started making noice which my neighbors will probably complain about ;)

But my fluke did not detect any volts on any of the 3 wires when I held them, 1 each time separately, unconnected in the back of the open clamp.

should I go complain to the seller or is there something else I can try?

Why I did find weird though is that the coils in the generator are touching each other. But that could be perfectly normal it just seemed weird to me as a newcomer.
 
So unless the wires are disconnected in the generator, you should be getting some AC voltage. Make sure you are using the meter right.
The wires are coated with a lacquer, so they should not be shorting out or anything. This is normal for any motor or generator.

Wind generators like this tend to make far more noise then power, so it might be working as designed. Not just what you want it to do.
 
Was your meter set for AC volts or for DC?
Coming off the windings would be AC. After a rectifier, if there is one, DC (actually pulses of DC).

Use a compass, also a screwdriver or paper clip, to see if the armature is magnetic.
If magnetic, it could produce power just by spinning. If not, it is a synchronous motor/generator which can only push current if externally excited by voltage.

If voltage is produced, you can test under load with a resistance heater. Light bulb would work for lower power (but varies in resistance with temperature.) I used oil-filled radiator heaters as a load for PV panels - in that case I needed an external DC rated switch. With AC output from turbine, the existing switches should be fine. Just measuring voltage you can calculate current and power.
 
The t5-600 mmeter was set to volts mode in which case it auto selects AC or DC. In this case it defaulted to AC before I put any wires through the clamp.
The generator is sold as 3 phase AC. There is no rectifier as far as I could tell which would be a good thing as I expected a 3 phase AC generator.
Use a compass, also a screwdriver or paper clip, to see if the armature is magnetic.
If magnetic, it could produce power just by spinning. If not, it is a synchronous motor/generator which can only push current if externally excited by voltage.
Could you please elaborate a bit? What is the armature in this scenario? The metal casing around the generator?
item 1 on the image below?
I have tested for magnetism on all exposed metal parts but it does not seem to be. So does 'externally excited by voltage' mean that I first need to connect it to a load (e.g. 3 phase electric heater) before I can measure any voltage and/or amps?

exploded view.png
 
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The t5-600 mmeter was set to volts. it auto selects AC or DC. In this case it defaulted to AC before I put any wires through the clamp.
Use the probes. The measuring voltage on the clamp part of the meter is designed for house hold AC power and is unreliable on anything else. And tends to be unreliable in general.
 
Could you please elaborate a bit? What is the armature in this scenario? The metal casing around the generator?
item 1 on the image below?
I have tested for magnetism on all exposed metal parts but it does not seem to be. So does 'externally excited by voltage' mean that I first need to connect it to a load (e.g. 3 phase electric heater) before I can measure any voltage and/or amps?

On your first image, see all the 12 flat pancake looking metal bit attached to the round spinning part. They should be magnets. No extra excite voltage needed. It spins, it makes power, assuming it works.
 
i watched the whole video and also some videos on the specific t5 model. None of them seem to show how to measure volts with probes on exposed wires. only how to put the probes into a power socket.

I did test the unit in a socket and it measures fine using the probes. the unit also beeps when touching the probes together in resistance mode which was demonstrated in an earlier t5 video as some sort if unit test if I am not mistaken.

could you please elaborate on how to use the probes in this specific scenario?
 
i watched the whole video and also some videos on the specific t5 model. None of them seem to show how to measure volts with probes on exposed wires. only how to put the probes into a power socket.

I did test the unit in a socket and it measures fine using the probes. the unit also beeps when touching the probes together in resistance mode which was demonstrated in an earlier t5 video as some sort if unit test if I am not mistaken.

could you please elaborate on how to use the probes in this specific scenario?

Probes need to touch the raw copper wires. You will need to strip the insulation off the red wires. One probe touches the copper on one red wire, the other probe on the copper on other red wire. Order does not matter in the way we are testing it. Both probes need to be connected at the same time.

Use some clips or strip the red wires so you can wrap the copper around the probes so they stay connected without you having to hold it on while you spin the generator. Nothing should be touching the end of the probes or exposed copper part of the wire when you are spinning it.
 
You will need to strip the insulation off the red wires.

To clarify, that is the flexible red wires coming out of the generator, not the red enamel solid wires of the field winding.

This alternator may produce hazardous voltages and currents. So don't touch the leads when spinning it. Best to set up first with alligator clips, otherwise hold probes by insulated handles.
 
6000 watts in Chinglish is 600 watts in English probably 300 watts expected.
The trick to these windmills has to do with tip speed. 90 MPH tip speed the blades are trimmed right to offer the rated current. If you use long wire runs these over-rev. Causing the tip speed to be way to high. The blades run in a poor air flow and poor power out. It is important to have a large wire from alternator to battery. An Ideal setup would be a very short wire run like found on Sailboats. If you put it on a tower and use a long wire run all bets are off.

To test the 3 windings short all three togather and spin it by have and you can feel the drag.

What to do is short all 3 wires togather and let the wind blow. You will be generating 0 volts and the windmill will never speed up enough to get into trim. The regulators work this was by shorting the 3 leads from the windmill together to force the windmill to charge a 0 volt load and this stops the blades from spinning. When the battery need power the short contactor opens and the blades rev up to rated speed and load and generate. If the wires are to long the blades will spin to fast and make a hell of a lot of noise and the output will suffer.
Does this make any sense.??

In a 20 knot breeze the blades will be running at 80 mph tip speed. The apparent wind on the blades will be like 90 to 100 knots. The blades are airfoils and are angled to optimize at this speed so the airfoil is in trim.

Setting up a wind turbine is an Art and it takes some time to get your head wraped around how they really work and how to optimize them.

All you really have to do to test the windings is short 20 of the 3 wires and spin the shaft and you will feel cogging. Then hook up the other 2 and repeat. The the other 2 and repeat. All 3 coils should behave the same. Then hook all 3 togather and you should feel a strong dull smooth 3 phase effect when turnong the shaft by hand. This test will tell you the coils are good. Put the device in service and run it and run some more test on it. Don't go out and order a 6 kw windmill controller. That thing won't do more than 400 watts on a good day.
 
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6000 watts in Chinglish is 600 watts in English probably 300 watts expected.
The trick to these windmills has to do with tip speed. 90 MPH tip speed the blades are trimmed right to offer the rated current. If you use long wire runs these over-rev. Causing the tip speed to be way to high. The blades run in a poor air flow and poor power out. It is important to have a large wire from alternator to battery. An Ideal setup would be a very short wire run like found on Sailboats. If you put it on a tower and use a long wire run all bets are off.

This unit might be slightly better as using 3 phase (and I am assuming higher voltage) is better for longer wire runs. But that alternator is tiny. I think the 300 watts might be a bit much unless spinning with a drill.
 
All you really have to do to test the windings is short 20 of the 3 wires

To clarify, that is the flexible red wires coming out of the generator, not the red enamel solid wires of the field winding
understood
Does this make any sense.??
a little yes, I am sure I will grasp it better as I get more experienced.

But that alternator is tiny.
What would be the alternator? is that the rotating ring of magnets on the inside on my first photo? And if so would that make the coils on the outside that are static (do not rotate) the stator? Or would I call the alternator the combination of both those parts or is that better called the generator?

I'll be sure to keep you guys updated here on how this turbine behaves tomorrow when I continue with this project.
 
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