Navitron Renewable Energy and Sustainability Forum

WIND TURBINES => Wind Turbines and associated systems => Topic started by: Robert Jurs on February 22, 2020, 03:33:04 PM



Title: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 22, 2020, 03:33:04 PM
We have a Proven 6kw wind turbine comissioned back in 2010. It has been decreasing in yearly output ever since. It peaked in 2011 with about 6500kw but in 2019 it was down to 2800kwh.
Data is public here:
https://www.sunnyportal.com/Templates/PublicPage.aspx?page=36209a41-ace0-4ec6-b6f5-14e3053f2691 (https://www.sunnyportal.com/Templates/PublicPage.aspx?page=36209a41-ace0-4ec6-b6f5-14e3053f2691)

There have been regular service with lubrication and checking that everything looks OK. All done according to the service manual.
Is it really to be expected to see these kind of declining numbers over time?

We have had some really stormy days the last couple of weeks, with wind speed up towards 17m/s, and the turbine never got over 3500watt peak output. Whereas back in the days a year or two after comission we regulary saw peaks at the rated max at 6000watt.
It is hard to be sure, but blades seem to rotate just as fast now as they back then.

So I am trying to find out if there is something that can be done to bring it back to the performance of its glory days:)
Do any of you know of issues that can cause this kind of decline?

It was latest serviced in summer 2017, where we saw that the slip rings were a bit used, so we sanded them down so they were shiny again.

Before service:
(https://i.postimg.cc/jWqJK0nV/6-Sl-beringe1-F-R.jpg) (https://postimg.cc/jWqJK0nV)

After service:
(https://i.postimg.cc/bZgsmCCm/6-Sl-beringe-EFTER.jpg) (https://postimg.cc/bZgsmCCm)

All help, info and suggestions are appreciated.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: oliver90owner on February 22, 2020, 03:47:48 PM
First off, what is the greenery behind those pics?  10 years of growth can quite easily affect the turbulence and wind speed.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Countrypaul on February 22, 2020, 03:49:12 PM
I know very little about wind turbines, but my first reaction was to wonder if it a 3 phase generator and has one phase gone down for whatever reason? can you check what each phase is producing before it gets rectified? (assuming that is how it works).  This assumes that your correct in your observation that the blades are turning as fast as they always did!


Title: Re: Proven 6kw Turbine performance decreasing
Post by: heatherhopper on February 22, 2020, 04:18:17 PM
Certainly something amiss for a few years. Should be at peak in anything around 10m/s or higher. If you have a service engineer, have they not given an opinion?
A bit more information about the complete set-up would be good otherwise everything is just speculation.
eg -
Presumably grid-tied?
Interface (rectification) original standard Proven?
Inverter(s) model?
Service history (any renewed/refurbished components)?
Wind speed records (preferably at something nearer head height rather than ground)?
Any more photos of the head?
etc


Title: Re: Proven 6kw Turbine performance decreasing
Post by: biff on February 22, 2020, 06:06:04 PM
I am guessing but I think Paul will say ,
      That the springs and dampers on the blades, need to be replaced,
                     Biff


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Philip R on February 22, 2020, 09:05:59 PM
If it is fitted with a permanent magnet generator, my huch is that the magnets in the PMG may have demagnetised. or the laminated poles may have rusted between the laminations, thus reducing the flux in the magnetic circuit.

Do you have design open circuit voltage figures for a given RPM, also short circuit current values too.

Philip R


Title: Re: Proven 6kw Turbine performance decreasing
Post by: camillitech on February 22, 2020, 09:27:33 PM
Methinks Oliver has 'hit the nail on the head', waaay tooo much greenery, time to get the chainsaw out  ;D Sure, it would probably benefit from a new spring set and blades too, that would certainly improve production but I'd deal with the shrubbery first.

(https://knowledgepoint.org/upfiles/15095806307643087.jpg) 

Good luck, Paul


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Greenbeast on February 23, 2020, 07:52:01 AM
Methinks Oliver has 'hit the nail on the head', waaay tooo much greenery, time to get the chainsaw out  ;D Sure, it would probably benefit from a new spring set and blades too, that would certainly improve production but I'd deal with the shrubbery first.

(https://knowledgepoint.org/upfiles/15095806307643087.jpg) 

Good luck, Paul

What is the effect of obstructions downwind of a turbine?
Still turbulence but much less? Any x'H'  figures for that scenario?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: camillitech on February 23, 2020, 07:58:58 AM
Dunno GB but it's only 'downwind' when the wind is blowing towards the object and whilst it may not have as much influence on production from certain directions it will cause excessive yawing and wear from others. Hard to quantify these things really  :crossed

Good luck, Paul


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Greenbeast on February 23, 2020, 08:09:11 AM
Dunno GB but it's only 'downwind' when the wind is blowing towards the object and whilst it may not have as much influence on production from certain directions it will cause excessive yawing and wear from others. Hard to quantify these things really  :crossed

Good luck, Paul

Ok, back to the scenario in the image, is the jist that you should stay at 2H between the obstacle and 20H (or thereabouts)?
So if i can't get more than 4-5H away from trees in some directions i should default to 2H high?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: camillitech on February 23, 2020, 08:21:20 AM
I 'think' that sounds reasonable GB but by far the best (only method really) is to put an anemometer up at hub height on the site.

Good luck, Paul


Title: Re: Proven 6kw Turbine performance decreasing
Post by: oliver90owner on February 23, 2020, 08:33:38 AM
As per that diagram, the whole rotor ideally needs to be out of any turbulence or reduced air flow.  I wonder how the kite would fly if it was dragged down into the turbulent airflow?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 23, 2020, 11:33:36 AM
First of all. Thank you all for the quick responses. I will try to give som more information about the setup.

System info:
Proven P11 6kW turbine
Mounted on 15 meters tower
Permanent magnet 300V DC (afeter rectifier I assume)
I dont know the make of the Recitfier, but it was mounted by the company who delivered the turbine in 2010.
Inverter is SMA WindyBoy 6000A
It is grid-tied to 220 volt

Service info:
Year 2010-2013 it was services yearly on service agreement from company.
There was some issues with noise from spings and bearings, so they eventually replaced the entire head, and wings in 2011.
From 2013 to 2017 there was no service.
Last service in 2017 was done by myself (non-professional). No parts were replaced.

Pictures of grid-tied installation:
(https://i.postimg.cc/MchpSjb3/Install-20190810-191033.jpg) (https://postimg.cc/MchpSjb3)

Rectifier turbine isolation box:
(https://i.postimg.cc/Y4mtbCK6/Rectifier-20190810-190958.jpg) (https://postimg.cc/Y4mtbCK6)

Pictures from last service in 2017:
All springs were more os less fine, they were all tightened according to specifications.

Springs all look like this:
(https://i.postimg.cc/NKcS28Qv/9-Fjederfod-sp-ndt-Vinge-3-EFTER.jpg) (https://postimg.cc/NKcS28Qv)

Rotor axel bearing1:
(https://i.postimg.cc/vDn071qY/5-Akselleje1-EFTER.jpg) (https://postimg.cc/vDn071qY)

Rotor axel bearing2:
(https://i.postimg.cc/1fHcMDpQ/5-Akselleje2-EFTER.jpg) (https://postimg.cc/1fHcMDpQ)

Yaw bearing:
(https://i.postimg.cc/DmC1X7Fv/14-Yaw-leje-EFTER.jpg) (https://postimg.cc/DmC1X7Fv)

Generator wheel and magnets:
(https://i.postimg.cc/cvtzzDT3/20170625-135217577-i-OS.jpg) (https://postimg.cc/cvtzzDT3)
(https://i.postimg.cc/k6sYSLM0/Magnets1-20170625-135155965-i-OS.jpg) (https://postimg.cc/k6sYSLM0)
(https://i.postimg.cc/GHV7vFrm/Magnets2-20170625-135203702-i-OS.jpg) (https://postimg.cc/GHV7vFrm)
(https://i.postimg.cc/wyq09F50/Magnets3-20170625-135213274-i-OS.jpg) (https://postimg.cc/wyq09F50)


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 23, 2020, 11:58:33 AM
Now regarding the placement and surrounding greenery. You are right, there actually is some small forest/greenery that was planted around same time as the turbine was built.

Today it is about 4-5 meters tall. As shown here in the picture, it is located to the west of the turbine:
(https://i.postimg.cc/TKZnk0Hp/Greenery-20170625-111446334-i-OS.jpg) (https://postimg.cc/TKZnk0Hp)

Also there is a barn/hall/building slightly the to north-east. Hieght of this is about 7 meters.
Picture from construction in 2017. Picture is taken directly from South direction:
(https://i.postimg.cc/Bjr4XPtr/Barn.jpg) (https://postimg.cc/Bjr4XPtr)

Google Maps:
https://www.google.com/maps/@55.5162614,12.0511463,200m/data=!3m1!1e3

So an areal view as good as I can do it. Picture is shown in correct North/south direction:
(https://i.postimg.cc/3kX0rhxF/Overview.jpg) (https://postimg.cc/3kX0rhxF)
The turbine is represented by the white star  ;D


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 23, 2020, 12:14:46 PM
I understand that the greenery might have some effects on output as it generates some turbulence. This can also be observed when wind is blowing from the West, and the East.
West is obstructed by the 5 meters of trees, and the East by the barn, and maybe even the main house.
We see a lot of yaw turning when wind is coming from these directions.
So I know this is not a valid point for comparing.

However when we have wind from North or the South it is pretty stabel. Not a lot of yaw turning.
The last 2-3 weeks have been wind more or less straight from the South (14-18 m/s), which is the direction that seems least obstructed, so this is where I do my comparisons.

The greenery to the south is probably around 70 meters away. And it is at lower. Ground terrain is 2-3 meter lower than foot of the turbine tower.

Note:
Buildings have always been there since commission in 2010. So I think that can be left out as a factor.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: heatherhopper on February 23, 2020, 12:19:14 PM
First impressions I would say (from personal experience) that you can rule out the turbulence issue - not perfect but then few turbine locations are.

Can't quite make out the scales on the rectifier interface or inverter display - what are typical voltage & amps for high wind speeds? Is the connected dump load operating much?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 23, 2020, 12:32:28 PM
 Sorry for making all this wall of text  whistle
But I think some context is important for you guys.

We live in Denmark. And at the time of the construction of the turbine, we were invoiced once a year, for electricity consumption. Basically this meant that production was substracted from consumption. So as long as we didn't produce more that we used, we essentially got full price, around 27 eurocent/kwH, as we would not have to purchase this.

However this year they changed the rules, so now production to grid/consumption is calculated hourly. Which means that we need to use produced electricity within an hour, or it will be sold to the grid for the price of 2,5 euro/kwH.

As we cannot constantly consume more than 3kWh anyway, we will not spend any signifficant amount of money for services, spare parts or consulting, as this investment will basically never be returned from production of the turbine.

So what I am trying to say is that I am looking for cheap DIY fixes. Or maybe doable by a electrician with no specific turbine knowledge.
I understand that I might not be able to do anything about it, but at least I will know why   ::)


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on February 23, 2020, 12:49:29 PM
Regarding Scales.
Here are a close up of the scales, as I remember correctly the Inverter showed around 1500watts at the time of the picture. However I cant document that :)

(https://i.postimg.cc/cttc4JCL/Volt-Amp-Scales.jpg) (https://postimg.cc/cttc4JCL)

But I have done some observations, where I calculated

Volt x current = watt
280x5 = 1400

And I seem to recall that it seemed to in the same ball park +/- 10%
But I will have a look again, under high wind speeds.

Regarding Dump load:
Actually we have never seen it actually working. Company tested it during installation in 2010.
But we have had several power outages over the last 5 years, and at no point during this, with the turbine spinning as high as 3000 watt, could we see or feel any heat of the dump load.

Could this have been destroying something, else in the installation, or turbine generator?
I was kind of thinking that the 3000watt generated during the outage might just be bumped in the cable or something  ??? 



Title: Re: Proven 6kw Turbine performance decreasing
Post by: Ted on February 23, 2020, 05:33:06 PM
Hi Robert,

apart from the things others have already mentioned there is also the inverter settings that it would be good to check and know what they are. Did you have these documented when the turbine was first installed?

In some circumstances it is possible they could have reverted to factory setting and are not set specifically for the Proven turbine.

As a first step you want to see what the inverter display shows (I'm not certain what the version of SMA inverter you have will show you) against the various input voltages, from say 300V to 500V.

If the voltmeter on the rectifier is showing the voltage running proportional to the turbine blade speeds (visually gauged) then the issue is most likely not with the turbine itself.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Other-Power on June 25, 2020, 07:18:22 AM
Shame this has gone quite.

I can see the turbine is still running on the SMA portal.

I would say voltage seems right, but peak power is low, tralling through the SMA data, even on a 'windy' day it only peaks at 3kW, this is on a day when 45kWh are produced.  I am inclined to think a dropped phase, maybe via the rectifer, or inverter settings.

Lets assume the inverter settings are correct for now.

If you have a phone with a good slow mo video function you can work out how fast the turbine is spinning and this may indicate if there is a dropped phase, also, you can measure the resistance of each phase by un screwing the electrical connections at the bottom of the tower and taking each phase in turbn, make sure the brake is on!  Proven used steel screw down clamp joiners for the cabling and these can go a bit rusty over time, I ten to wip these off and use solder, the one that I dont like is the joiner in the head itself as this is hard to check unless servicing. 

Any way a few things to check over first before the inverter settings, would be good to know how you get on.

It sounds like the new hourly metering is a bum deal for you, have you got somewhere you can use the spare electricty as heating, there are cheap devices out there that can automatically re distribute the spare power as it varies from the turbines output.

Cheers

Jonathan

(hi ted!)


Title: Re: Proven 6kw Turbine performance decreasing
Post by: camillitech on June 25, 2020, 07:34:58 AM
Hi Jonathan,

and good to hear you again, do they not vibrate like feck with a 'dropped phase'  ???

Cheers, Paul


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 25, 2020, 03:15:44 PM
To be honest, I kind of gave up on this one. As I was stuck at the "measuring the rotation speed of the blades". But I am pretty sure that they are spinning more or less the same speed now as when we initially got the turbine. Just by looking at it, and remembering. But of course I know this might be hard to remember.
But when wind speeds are close to 12m/s, I am pretty sure that it cant spin any faster than it does at that point - or it would fly apart. And at the very least it should peak out at more than 3000watt at that point.

But the new info regarding the dropped phase - That I can check  :)
Sorry for ghosting you guys. It is great to see you are actually wanting to help out.

I will try to test resistance on the phases out in the bottom of the tower, and inside before the rectifier. At some point, I can even also get access to the part inside the turbine head, we just need to take it down for servicing. Fortunately we have the means to do this by ourselves.

I will keep you posted.




Title: Re: Proven 6kw Turbine performance decreasing
Post by: biff on June 25, 2020, 03:58:49 PM
There is also the problem with the Blade springs getting weak and according to Paul, that also causes the power to drop off.
            Biff


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Other-Power on June 25, 2020, 05:41:23 PM
There is also the problem with the Blade springs getting weak and according to Paul, that also causes the power to drop off.
            Biff

Iím not sure we would expect to see a drop of 50% with tired springs, to me, on the face of it this alone would not cause such a big drop in peak output.

Hopefully something will come to light with a little more checking.  I think there is a herbal buzz and desire to get things working , letís keep plugging away and Iím sure it will come good.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 12:31:02 PM
Ok. Now I have stopped the turbine, and cut it off at Grid-isolation point.
And I have pull out the 3-phase wires coming directly from the turbine.

Here is a picture of my measuring setup:
(https://i.postimg.cc/BjvR2Tyz/20200628-130041-LI.jpg) (https://postimg.cc/BjvR2Tyz)

Blue arrow from the bottom left, is cable directly from turbine.
And I measured the resistance (ohm) between all combinations of phase wires.

I am not totally sure how to measure, but I assumed it was across/between the phase wires.
(I set my multimeter to measure Ohms, in the 200ohm range) But it did not settle on a static number, instead it fluctuated from around 0.2 ohm up to as high as 12 ohm. I dont know if this is right?

Here are my results (in ranges) of Ohms:

Brown <-> Black  = 0.3 - 8.0 ohm
Black  <-> Grey   = 1.6 - 11.1 ohm
Grey   <-> Brown = 1.2 - 9.0 ohm
Blue = Ground wire

I also made the same measurements at the base of the turbine tower, and they were more or less the same, with fluctuations, in the same ranges.

Note: There are about 30 meters underground wire between the rectifier box and the turbine tower base.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 12:51:58 PM
Regarding the type and the settings of the inverter. I have a Webbox connected to it the inverter, which means I can see a lot of settings. Unfortunately I don't have documentation on how it was initially set up during installation.

Name: SMA Windyboy 6000A
Model no: WR6KA-08

Inverter manufacture docs:
https://files.sma.de/downloads/WB_Par-TEN093910.pdf (https://files.sma.de/downloads/WB_Par-TEN093910.pdf)

I also found this documentation on the turbine itself:
This beats the doc we got after delivery by miles  ;D in terms of details.
https://www.energymatters.com.au/images/Proven%20Energy/Proven6%20300Grid%20Connect%20Manual_06.pdf (https://www.energymatters.com.au/images/Proven%20Energy/Proven6%20300Grid%20Connect%20Manual_06.pdf)

Settings in My inverter:
1   ACVtgRPro   253   V
2   AntiIsland-Ampl   0   grd
3   AntiIsland-Freq   500   mHz
4   Betriebsart   Turbine   
5   Control   Auto   
6   Default   GER/VDE0126-1-1   
7   dFac-Max   4   Hz/s
8   dZac-Max   620   mOhm
9   E_Total   45486.4   kWh
10   Fac-delta-   2.45   Hz
11   Fac-delta+   0.19   Hz
12   Fac-Limit delta   2   Hz
13   Fac-Start delta   1   Hz
14   Fac-Tavg   160   ms
15   Fan-Test   0   
16   h_Total   56876.72   h
17   Hardware-BFS   2   Version
18   I-NiTest   16000   mA
19   Inst.-Code   0   
20   KI-Wind-Reg   0.005   
21   KP-Wind-Reg   0.02   
22   LDVtgC   0   V
23   Phase   -----   
24   P-HzStop   0.05   Hz
25   P-HzStr   0.2   Hz
26   Plimit   6000   W
27   Pmax   6000   W
28   PowerBalancer   Off   
29   P-WCtlHzMod   Off   
30   P-WGra   40   %/Hz
31   P-Wind-Ramp   1000   W/s
32   Ripple-Ctl-Frq   1605   Hz
33   Ripple-Ctl-Lev   8   %
34   Ripple-Ctl-Rcvr   auto   
35   SMA-Grid-Guard   2.12   Version
36   SMA-SN   2001406264   
37   Software-BFR   1.36   Version
38   Software-SRR   1.36   Version
39   Speicherfunkt.   Keine Funktion   
40   T-Max-Fan   90   grdC
41   T-Start   10   s
42   T-Start-Fan   70   grdC
43   T-Stop   300   s
44   T-Stop-Fan   50   grdC
45   Uac-Max   260   V
46   Uac-Min   198   V
47   Uac-Tavg   80   ms
48   UdcWindStart   250   V
49   Upv-Start   250   V
50   Usoll-Konst   600   V
51   Wind_a0   -337848.8   
52   Wind_a1   3659.94   
53   Wind_a2   -13368.31   E-3
54   Wind_a3   16526.37   E-6


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Alan D on June 28, 2020, 01:22:18 PM
You need a reading from any one of the three phase turbine cables to the blue / earth cable
with the meter on the highest resistance range.

If there was the slightest movement " mm. " of the rotor while testing the resistance between
phases this will upset the low range resistance readings.

Is the turbine down. Blades tied / roped to stop the slightest movement.

Where is the blue / earth cable connected at the turbine end. To the local tower Earth ?

Are the three phase slip rings / brushes all shiny. No sign of wear / burning / pitting.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 02:12:13 PM
Thank you for replying to quickly. I really appreciate it.

Ok. I now tried to measure resistance between the 3 phase wires and the ground/earth (blue wire).
But I am having trouble seeing any changes at all.

Note: Rotor is totally static, with full break on.

Here is what what I can do on my multimeter:

2000k - 004 with no change
200k - 04.6 with no change
20k - 4.60 - small change
2000 - (1) infinite - with no change
200 - ~38.5 with no change

When I use the highest ranges, I get no change at all from no connection.

Only range I can see any changes is by using 20k ohm range
With no connection to multimeter it shows 4.62ohm
When I connect it across blue, and phase wires it only makes a slight change to something like 4.60ohm. From what I can see the behavior is the same on all 3 wires.

If I use range 2000ohm I just get (1) - infinite in display whit no changes on all 3 wires.
If I use range 200ohm it shows around 38.7ohm without any connections, and it doesn't change when connected to any of the wired.

Cloud it be somenthing with the ground wire?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 02:23:27 PM
Regarding the Ground wire.

Hmmm...  I dont know where it is connected. At the tower base I cannot see any connection to the tower.
If you look at the start page of this thread, you can see that there are only 3 slip rings, so ground is not routed through the Yaw turning.
I have looked at all the pictures I have of the turbine being serviced and I cannot see where the ground wire is mounted.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 02:29:45 PM
I did some more research in the assembly instruction manual that I linked earlier, and in their setup they only use a 3 wire cable to the slip rings. There is no sign of the round wire that I have. I'll try to see if it is mounted to the tower base somewhere.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 02:53:39 PM
I went out and tried to do a connection test across the tower and the ground wire going up to the turbine, and there IS indeed a connection, so my guess is that ground wire is connected to the tower base, where the other wires goes to the slip rings at the top of the tower.

However there was some kind of "signal" noise in the tone/sound that the multimeter does to indicate connection between the two measuring points.
I don know if this could indicate a loose ground connection? Or if this matter at all.

If I understand the schematics correctly I dont think it uses the ground wire for anything. Other that standard safety reasons. Or am I wrong?


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Alan D on June 28, 2020, 03:13:41 PM
The cable in the control panel. Brown / Black / Grey / Blue. Goes directly from the control panel up inside the shaft to the slip rings with no junction box.
If so the Blue / Earth is not connected to the turbine.
The turbine is still up. ?.  
You have no access to the slip rings for testing / visual inspection.
Because there is no earth connection between the turbine and the panel. ( Why ?  facepalm )
For testing the winding insulation resistance. You need to run a single core cable from the turbine tower / earth connection to a location next to the control panel.
With the meter on the 2000K range not connected what does it display.
With the meter on the 2000K range connect one meter lead to the single core cable ( connected to the turbine tower earth connection ) and the other to any of the three ( Grey / Black / Brown ) What does it display.
If you cant check the slip rings / brushes visually for erosion / pitting / wear / burning the electrical readings are a bit iffy
The readings taken on the 200 Ohmn range between the ( Grey / Black ) ( Grey / Brown ) (Brown / Black ) Should be the same and not moving about. 12 Ohms ish.
When the meter is on 200 Ohmn and not connected. Does it display the same at all times.
The slightest blade movement ( couple mm backwards / forwards ) would generate a voltage which would make the Ohms readings false.

Ref " I also made the same measurements at the base of the turbine tower, and they were more or less the same, with fluctuations, in the same ranges. "

This cable must go from the control box to a box / isolator at the base of the turbine tower. What does the Blue / geen/yellow tape cable do in this junction box. ?
Is there another cable going from this to the turbine tower earth connection.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 28, 2020, 04:13:29 PM
Yeah. The turbine is still up so I don't have direct access to inspect the slip rings. But we will take it down later this summer, at that point I will do the check, and tests :)
I will do the test, with running a ground cable from the turbine generator to the control box. And measure across to the 3 phases again.
Hopefully this will give some useful results.

I just wanted to know if there was anything I could do now, without taking it down.


As for your other questions - here are the answers:

There is a junction box inside tower base, however, it is just connecting the 4 wire cable from control box, 1-to-1 to another 4 wire cable that goes to up the tower to the turbine top. But my guess is that the ground is terminated/connected to the tower, before going to the slip rings.

My multimeter at 2000k Ohms not connected it shows 004
When connected across blue/ground to one of the 3 wires there is no change = still 004

Multimeter at 200 Ohms range and not connected, it starts at around 38.6 and it slowly goes down in 0.1 steps. Until it settles at around 32.0 after 5mins.

Turbine wings are totally fixed. With a break activated on the axel of the blades. So I don't think it can move at all. It looks and sounds totally static.

I guess the green/yellow tape in the control box, just indicates that they used the blue wire for ground :)

In the junction box in tower base, cables "changes" color like this:

From box -> Turbine
Brown -> Black
Black -> Black
Grey -> Black
Blue -> Green/yellow

The Green/yellow wire in junction box goes directly into the 4 wire cable (black/black/black/green-yellow) that goes to the top of the tower.
There is no other connections in the junction box. Only these 4 wires straight through.

There is no other cabled between control panel and the turbine.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Alan D on June 28, 2020, 04:59:08 PM
Ref : " In the junction box in tower base, cables "changes" color like this:

From box -> Turbine
Brown -> Black
Black -> Black
Grey -> Black
Blue -> Green/yellow

The Green/yellow wire in junction box goes directly into the 4 wire cable (black/black/black/green-yellow) that goes to the top of the tower.
There is no other connections in the junction box. Only these 4 wires straight through. "


The three black cables going up to the top would be directly connected to the terminals on the  top of the slip rings. There is no other connections.
The Earth cable can not be connected to the metal work because it would get ripped off as the turbine rotates.

Unless the Earth cable is terminated inside the vertical tube that the cable / brake rope goes to the top in.
Reading the installation manual it does not mention Earth connection to be made at slip ring internal assembly.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: biff on June 28, 2020, 05:37:32 PM
Maybe the metal tower is the ground earth ,
      Maybe.
       Biff


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Alan D on June 28, 2020, 09:01:01 PM
If there is no movement at all on the rotor ( Turbine not producing a small voltage ) it sounds like your test meter is not to good.
If I wired a 12 volt tungsten bulb across my test meters when testing on Ohms It would give a stable constant reading.
If I wired a 12 volt tungsten bulb across any two phases of my turbine when it had stopped. Then turned the rotor 10 deg the bulb would blow.
( very small movement produces a voltage. )
For Ohms / MOhms testing there must be zero volts.
If you test at the base of the tower junction box from any black cable to a good metal part of the tower with your meter on 200K
The meter should display the same reading with it turned on.
And the red and black probes are open circuit. ( Not connected )
And the red or black probes are connected to any black cable and to a good metal part of the tower. (not galvanised. scrape a line into the tower with a small hacksaw )
The display reading should be constant.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on June 29, 2020, 10:40:33 AM
Thank you all for all the help up until now. Your quick and useful suggestions have given me a lot more insight, in how my setup is working  8)

I agree that it sounds like my test device, might not be working properly. So I think it is time to get it replaced.

The turbine is now back in service, so I can't do any more testing right now. However I will get a new and proff multimeter soon. And we will take the turbine down for service later this summer, at that point I will test as suggested, and also test and check the slip rings.

I will let you know about the progress.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Alan D on June 29, 2020, 01:58:45 PM
In the control panel there are two Schneider 24 volt D.C. three phase contactors.
One contactor is energised to feed three phase turbine supply to three phase bridge rectifier that feeds the 6 K.W. Windy Boy.
The other contactor is energised to feed three phase turbine supply to three phase bridge rectifier that feeds the dump load.

Where does the 24 volt D.C. supply come from that energises the contactors. ?

Only the one contactor is energised while the turbine is running feeding the Windy Boy.  ? The other one should not be energised.

Is there any carbon / burnt smell near the contactors.

By Design I would have expected the three phase bridge rectifiers to have been mounted onto an aluminium heat sink. They look like they are just mounted onto the internal metal side of the control panel. ? If its been working for years that's O.K. just about.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: Robert Jurs on July 01, 2020, 11:52:36 AM
Very nice to know how this is actually supposed to work :) All the different components are starting to make sense to me now. Thank you for explaining.

To answer your questions:

Regarding 24V power to contactors. There is a built in controller board, with a powers supply in the left side of the box.
This feeds the contactors.

(https://i.postimg.cc/nMKgqkCJ/20200630-125515-LI.jpg) (https://postimg.cc/nMKgqkCJ)

Regarding the rectifiers, you are correct :) they are indeed mounted to an external heat sink. It did just not show on the previous pictures.
But there you can see it on the outside of the box:

(https://i.postimg.cc/zV6Cvm8X/20200630-125437.jpg) (https://postimg.cc/zV6Cvm8X)

Also there is now noticeable burnt smell inside the box. 

And I have now observed the workings of this box for some time.
I can confirm that the contactors does indeed switch back and fourth between them. At the time of observation (10 mins ago) wind speed is very low, and the turbine generates between 0 and some 400watts. So I assume the controller board switches of turbine->Inverter when the turbine does not generate enough power to active the inverter.
And then when it is rpm up it switches back to turbine->inverter. Which explains the contactors switching back and forth between the two.


Title: Re: Proven 6kw Turbine performance decreasing
Post by: heatherhopper on July 03, 2020, 07:16:14 PM
Robert
Good to see you are making some progress and I hope you will keep us informed through to a result (good or not). We all learn a bit if a thread plays out. There is another similar(ish) recent thread you may find interesting here:
https://www.navitron.org.uk/forum/index.php/topic,31818.0.html

I appreciate you have been measuring all sorts of things and I'm not sure what you have determined thus far about AC delivery from the Turbine but the wind interface (rectifier etc) seems a bit suspicious even if the AC delivery is not right.

By way of some background you may not be aware of. There were various problems with these turbines around the time yours was installed often related to the Proven wind interface (the rectifier etc). Coincidently SMA were warning about inadequate over-voltage protection for their Windyboys and produced their own, good but expensive, solution - presumably following some destructive events and warranty claims. Seems a number of different interfaces were devised/installed before the problems abated.
The interface usually just needs to provide simple AC-DC rectification and overvoltage protection, via a dump load, for the Inverter. Yours seems an odd and over-complicated configuration and certainly not the basic Proven issue I have seen.

The "switching" of the contactors you have described does not make any sense and I can see no logic for the dump to operate at all on low voltage. You said previously you had not seen the dump load operating. Are you sure it has not been doing so at times you would have expected higher output? The dump load only needs to be activated to protect the Inverter from very high voltages and is usually set somewhere a little less than the max 600v. The Turbine itself can run quite happily, although noisily,  unloaded. For a grid-tie system I imagine activation would only happen occasionally in high winds and only for any sustained period if the Inverter could not synchronise with the grid since the grid provides a permanently available load. If you have some information about the interface (schematics, manual, controller type, dump resistor size etc) that would be interesting.