10 kw Wind Turbine

Buchanan1
Buchanan1 Registered Users Posts: 9
Was referred to this site.

A year ago, my contractor installed a 10 kw Wind Turbine (mfg'd in China),
two 6 kw Aurora inverters send AC power to the grid on a net metering agreement with BC Hydro.

One aurora inverter didn't work right away (even tho wired parallel), but after a month it "kicked in", and things were fine for about 10 months or so.

During a huge windstorm overnight two months ago I heard the turbine's blades spinning faster and louder than ever before. I sensed something was wrong because the turbine blades were not turning out of the wind (as they're supposed to do).
The next day, the turbine blades were not turning, the two 6 kw Aurora inverters were OFF, no power lights, no nothing.

Contractor came out, after checking the "controller box", he thought the "resistor block" was dead. Then he said "no, both inverters are fried".

Pictures can be seen at my Flickr site:
http://www.flickr.com/photos/southsl...7617702085418/

PowerOne in California, after 5 weeks, sent us one new inverter (the other was apparently "fixable" here). Contractor hooked it up yesterday, and after about 4 hours of wiring, declared that the new inverter didn't work! He phoned Power One and demanded a new one be put on Air Express, as I'm ready to send EVERYTHING back.

Nobody seems to have any idea WHY overvoltage entered the inverter(s). The wind turbine doesn't have a "memory", but from the sound it made that stormy night, it must've been HUGE voltage from big RPMs.

One important thing: The property has 138,000 transmission line running approx. 300 feet from the wind turbine. Turbine's tech cables were trenched underground, crossing underneath the transmission line into the shop where the controller box and inverters are located (including a heat dump).

My question (and the contractor's) is: during the storm could "pick-up" (induced voltage) from transmission line's 2 circuits, 3 phases each, have "momentarily frozen" the wind turbine's safety controls (via static? or ?) so that overvoltage to the inverters occurred?

B.C. Hydro won't tell me anything, but I need to know what happened so the contractor can prevent it occurring again. The inverters were still under warranty, as was the wind turbine, but nobody is saying anything!

I will ask my contractor to join in this conversation, because I have NO elec know-how (as though you hadn't guessed! ).

thank you for any ideas of what caused what, and how I can prevent this happening again.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 10 kw Wind Turbine

    Sorry to hear about your problems--Those type can be difficult to solve.

    First, regarding your Flcker link--It did not get placed correctly. Looks like somewhere along the cut and past, the real link got shortened with the "..." in the middle.

    Second, looking at the inverter specifications, it appears that all of the overspeed/safety circuits should be in the Wind Turbine--So, no matter what happened with the inverters--the Wind Turbine's own controller(s) should have activated the various safety systems (furling, feathering, brake, shunting alternator output, etc.).

    Either the safety systems/circuits failed, or by the time they kicked in, the wind was so heavy that the system(s) could not do their job. If there was only one safety system (furling based on wind loading and no electronics at all--you probably need to pull the turbine down or go up in a basket and inspect for damage/poor design.

    In general, it is a good idea to have several independent shutdown systems--including a brake / mechanical RPM limiting system. Many designs just increased load on the alternator to limit RPMs and that is not enough (electronics fail, wind energy exceeds design limits and alternator overheats, etc.).

    Lastly--I am a bit confused about the inverters... They don't seem to have any method to support parallel operation (one wind turbine, two inverters) either in the specifications or in the functional block diagram (just a quick Internet search for specifications).

    So, I am not sure how the two inverters functioned together in parallel when doing MPPT (tracking) on the the Wind Turbine. And second--if one lost control or decided to try and shut down the wind turbine (over power, over voltage, etc.)--Would that be communicated to the second inverter so they could add load to the turbine together (rather than one 6 kW inverter attempting to sink/stop a 10 kW inverter by itself)?

    And, did your inverters have the dump load + RPM monitoring options and how where those programmed to behave?

    In any case--Unless the design engineers from the turbine and inverter companies participated here (which I highly doubt, and I would probably recommend that they not from a company/publicity point of view)--About the best we can probably do is ask questions like above.

    Perhaps, somebody else has a similar setup and can share their experiences here and what they may have found out.

    Without the inverters/wind turbine design information, and a lot of studying--I am just taking wild guesses here.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 10 kw Wind Turbine

    wow, we got a referral!:D

    welcome and sorry to hear of your misfortune. i doubt that any of us may be familiar with your setup and equipment, but we can certainly speculate as to what went on there. there is no guarantee that we may hit upon the actual problem for you, but what do you have to lose?
    could this have been an emp pickup? sure, but i doubt it came through the ground to the wires as it most likely could've been picked up above ground and transmitted to the inverters via the wires if it could not break through the wire insulation to jump to ground.
    now you didn't say, but do you have any lightning protection in place? the use of such protection may help even though it is not a guarantee no harm will come to your stuff. also grounding everything well also helps.
    given the state of the wind at the time it may be possible the turbine exceeded the input voltage that the inverters can take depending on how said turbine handles such over wind conditions. you should be very happy given the failure of the inverters that the turbine did not self-destruct as once there's no load present, that storm could free wheel the turbine beyond what it can physically take and was what you were probably hearing was it taking that wind with no load. i have never heard of any turbine surviving under such conditions before so count yourself very lucky.
    you also indicated a problem with one of the inverters in the beginning and that could have a potential to crop up later and wound up dumping everything into the one inverter still working until it soon popped from the stress.
    as i stated much of this is guesswork
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: 10 kw Wind Turbine
    Buchanan1 wrote: »
    ...... A year ago, my contractor installed a 10 kw Wind Turbine (mfg'd in China), two 6 kw Aurora inverters send AC power to the grid on a net metering agreement with BC Hydro......

    Sorry for your loss. I hope the factory and contractor sort it out.

    Generally, small wind is a non-starter. Too much maintenance, and too much can go wrong - even with proper maintenance.

    The wires in the trench, were they in PVC or metal conduit ? power cables only, or were there signal/control line in there too ? 24" underground, I can't see them picking up much of anything. Surge arrestors at each end ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • McClary's Electrical
    McClary's Electrical Registered Users Posts: 21
    Re: 10 kw Wind Turbine
    mike90045 wrote: »
    Sorry for your loss. I hope the factory and contractor sort it out.

    Generally, small wind is a non-starter. Too much maintenance, and too much can go wrong - even with proper maintenance.

    The wires in the trench, were they in PVC or metal conduit ? power cables only, or were there signal/control line in there too ? 24" underground, I can't see them picking up much of anything. Surge arrestors at each end ?




    Good point, I'd be curious to know from the op if the control wiring and power wiring are seperated in different conduits, and if so how much? Hopefully not in same conduit
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    Excellent comments, folks, thanks!

    I'll try to get the electrical contractor involved in the discussion on Monday.

    I'm sure you understand how frustrated I am.
    ...and grateful, now that I was referred to this site.

    As to the Flickr pictures, this should work:
    http://www.flickr.com/photos/southslope/sets/72157617702085418/
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 10 kw Wind Turbine

    The blown blue things are probably MOVs--designed to take high voltage surges and short them to ground. If you have a lot of energy--that is what will happen.

    I cannot tell exactly what is happening with the terminal block (DSC03687), looks like perhaps an overheated terminal end and/or some separating/fraying wire.

    Oh, I see the next picture--Possibly an over crimped wire that failed (1/2 cut through then failed from mechanical strains and/or high current flow through reduced cross-section causing over heating?

    Is this in the turbine, inverter, or some interface unit?

    The inverters--That appears to be a tight area in regards to cooling--Had you ever noticed a hot spot over by the inverters when the the turbine was operating near full load?

    Also, the turbine has an anemometer on the nacelle. Did you get any logged readings from either the anemometer or turbine itself (wind, rpm, power) around the time of failure?

    It looks like the turbine uses an electric yaw motor to control pointing into the wind. Are there any other means of stopping the turbine when needed (brake, does not look like the blades feather, internal shunt/load, etc.).

    Hmmm... Electric box appears to be all plastic... Trade off of, perhaps better weather/water proofing of plastic vs the better RF / Lightning resistance of metal and shielded components/systems. Although--it looks like the entire nacelle may be metal?

    This looks like the Wind Turbine Manufacturer:

    Shenzhou Wind-driven Generator Co., Ltd

    One website (I don't know anything about the following site) that was created because of Yaw Motor / Control failures in these units:

    http://wind-water-power.com/index.html

    One of the quotes from above website:
    yaw motor failure, controller failure, turbine overspeeds, burned up inverter

    I would be a bit concerned about a 10kW electric heater below the electronics/inverters... Understand that the 10kW heater is only energized during a power outage (?).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 10 kw Wind Turbine

    that could have been lightning or a strong emp that blew out the movs. told you guys those things explode.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: 10 kw Wind Turbine
    niel wrote: »
    that could have been lightning or a strong emp that blew out the movs. told you guys those things explode.

    Or unregulated voltage from the turbine as it was over-reved. If you can be sure it popped like a firecracker, or slowly cooked. If it was EMP, it's odd only 1 went.

    They are made to absorb EMP, and survive x hundred jules of power. EMP should have done all of them.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 10 kw Wind Turbine
    mike90045 wrote: »
    Or unregulated voltage from the turbine as it was over-reved. If you can be sure it popped like a firecracker, or slowly cooked. If it was EMP, it's odd only 1 went.

    They are made to absorb EMP, and survive x hundred jules of power. EMP should have done all of them.

    that's a maybe on the turbine overvoltage, but my money would still be on lightning or emp. they all don't necessarily need to be fried and the movs don't absorb it, but rather pass it along to ground up to their ratings. they usually pop when their ratings are exceeded and lightning is more apt to do that than emp, but it can still happen on emp as well. the other movs may in fact be bad now if they passed too much current, but there's no guarantee all movs will explode when exceeded on their ratings either.
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: 10 kw Wind Turbine

    A user had had other issues with those turbines which might be related, this one from 2007:
    http://navitron.org.uk/forum/index.php?topic=860.0
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    Thanks for that link.
    The reference was to a company in China.
    Presume there is more than one turbine company in China? or is it my turbine's manufacturer?

    To answer this: Is this in the turbine, inverter, or some interface unit?
    That "frayed wire" is in the turbine controller box, adjacent to the two 6 kw Aurora inverters (all located in the shop). The turbine is 400 feet away from the shop.

    Other questions I'm not qualified to answer.
    I'm just the owner, LOL.:blush:
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: 10 kw Wind Turbine
    Buchanan1 wrote: »
    Thanks for that link.
    The reference was to a company in China.
    Presume there is more than one turbine company in China? or is it my turbine's manufacturer?

    You tell me! That link references Shenzou, which Bill thought might be your turbine.
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    Seems very close to the name on the operating manual download:
    The guide has been carefully checked by engineers of Yangzhou Shenzhou Wind-driven
    Generator Co.,Ltd (SWG).
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 10 kw Wind Turbine

    The link I provided about the Yaw motor/controller failure appears to be a an older model (possibly 5kW) unit from the same manufacturer as you.

    "Redriven Wind Turbines" which have had lots of failures too (follow my original link for Redriven links), according to this person, are also made by SWG:
    I started my investigation trying to find out about the Chinese company that make Redriven’s turbine. I did a search with the terms Redriven and China and came up with shipping documents http://www.importgenius.com/importers/redriven.html
    Yangzhou Shenzhou shipping to Redriven in Canada.

    As soon as you go to the SWG - Yangzhou Shenzhou web site it is clear that is the Redriven product. Same look, same tower, same hydraulic lifting mechanism.
    http://www.f-n.cn/

    In the comments from the above link--Redriven told a commenter that Redriven no longer purchases from SWG (blades or whole turbine--not clear? Stopped sometime in 2009?).

    Also, if you follow some of the other Redriven related links, there are articles about no longer purchasing blades from that Chinese supplier.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    BB,

    Oh my God!
    Thanks (I think).
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 10 kw Wind Turbine

    By the way, my guess was based on the photo of your Turbine Controller. It has SWG, WWW.F-N.CN, and Yangzhou Shenzhou Wind-driven Generator Co., Ltd on the front.

    I could not quite make out the turbine name plate on my netbook computer--but on a larger screen, the name plate has SWG and Yangzhou Shenzhou Wind-driven Generator Co., Ltd too...

    By the way, when looking to debug--If I understand the turbine design correctly... There is a "dead man's switch"... A three phase solid state relay on the Alternator output. A line to a Cap and Microprocessor Controller, and the output of the relay is probably just shorted together.

    The micro processor sends a pulse to the relay every XXX mSeconds... If the processor wants to stop the turbine, or goes out to lunch, the pulses stop and the Relay closes--basically shorting the output of the Alternator.

    A shorted alternator has very high torque and "should" load down the blades enough to stop turning--or at least turn very slowly.

    If the Relay (or wiring) failed, the processor would not shut down the turbine. If the wind was very high speed, it is possible that the wind continues to drive the blades and will actually over heat the alternator/relay/wiring and fail that way.

    Typically, over-speed failures will cause blades to shed.

    In your case, it looks like an over-speed took out the inverters (too fast turning alternator over voltages the inverters).

    Why the turbine did not turn from the wind--Could be either a controller failure or yaw motor failure (or too much wind loading stopped the yaw motor?). Or--it could be lightning hit (did you have, do you get lightning strikes in your area?).

    Presumably, the 10kW turbine should have some sort of mechanical braking systems (besides the relay shunt)?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 10 kw Wind Turbine

    Buchanan1,

    By the way, I did send you an PM a day or two ago too (Look at the Private Messages link in upper right if you have not seen it yet).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    yes, I did receive your PMs for which I thank you very much.

    Talked to the contractor today; he'll be here in 4 or 5 days with the new Power One Aurora Inverter (the third one!!!!, which is apparently on a plane now but has to go through Customs first).

    I'll show him all these postings, and will jot down his replies. Mentioned to him that Redriven doesn't buy from SWG anymore; he wasn't aware of that.

    Everyones' posts and shared concerns are appreciated.
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    The wind turbine is operational again...or I should clarify that we've installed a new (the third one) 6 kw Aurora inverter.

    In addition, the contractor has implemented a braking function so that when the controller senses either a certain RPM, or voltage, or windspeed, or turbine head temperature, it will apply the 10 kw dumpload in parallel with turbine output, thus loading the turbine and dissipating excess energy.

    By the way, the last data in the broken 6 kw inverter was 460, well within the safety zone, so it's up to Power One to figure out why it's broken. There had, in the other one, been a missing MPPT field, but not the last inverter.

    My apologies the contractor wasn't able to get on this site to answer each person's comment, but I did send all comments to him to read.

    From midnight to early this morning, we've produced 16 kw.
    Seems to be working well.

    Thank you for the suggestions!
  • System2
    System2 Posts: 6,290 admin
    Re: 10 kw Wind Turbine

    Hello Buchannan,
    your turbine is a Yangzhou Shenzhou turbine
    also the controller is from this company.
    and the tower is also original Yangzhou Shenzhou

    The Aurora inverters are not made to parallel the inputs and put them on the same grid.
    When doing this you need a transformer between one of the two inverters and the grid.
    also you need to set the RISO setting on the inverter that is connected to the diversion transformer in the OFF position.
    To do this you need a password and the aurorainstaller software

    When the grid fails the original dumploads 3x can not hold the turbine in high winds.
    you must double this dumpload system .

    Then I must advice you to connect a active circuit breaker in the main DC leads to the Aurora inverters.

    When the grid fails or the dc voltage rises above 550 volts the connection should fall off.
    This way you protect your expensive inverters.
    In time there will be a repeat of your brake down.
    you should prevent this from happening.

    Looking at your foto's i would say that you had a overvoltage on the dc bus,
    We have had the same problem with our first installation
    even a 5kw Yangzhou Shenzhou was able to fried up 2 inverters.

    Kind regards

    Cor van Houtum

    Draaistroom Nederland
    distributor of Yangzhou Shenzhou in The Netherlands
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    Hello Cor van Houtum,

    I was most interested to read your comments.
    Thank you for participating in this discussion.

    I have sent your reply to my contractor.

    One small point I can mention is that we do have a transformer.
    Will post the picture in a few minutes.

    Thanks again...very good of you.
  • Buchanan1
    Buchanan1 Registered Users Posts: 9
    Re: 10 kw Wind Turbine

    This picture shows the transformer, installed during construction last year.

    4831513305_8fb1b714bd.jpg

    Thank you.