Wind and MPPT

Discussion in 'Charge Controllers' started by Minnesota, Jan 5, 2011.

  1. Minnesota

    Minnesota WindyNation Engineer

    I just did a vid on solar with an MPPT GTI. The MPPT gave about 44% more power vs a battery tied setup (just a power diode).

    I am wondering if anyone has results of MPPT with a turbine vs. just a bulk DC charge controller.
    timber likes this.
  2. murray2paddles

    murray2paddles WindyNation Engineer

    Not sure if this is exactly what you are asking for but it is on MPPT results in wind.
    On one of my test inverters " Sun DC 500, 10.8-30. I had it running off of a WN 500 & WN 750
    The inverter was able to keep the turbines clamped to low volts, this was also producing very good watts so it was also indicating it was allowing the amps to build.
    I was surprised when I disconnected the 750, although the watts dropped off to near half the volts remained the same proving to me that the MPPT was controlling both turbines at the same time.
    Larry has reported to me a great success using the batteries but not as a bank but to clamp the volts tying in up to 4 turbines at a time, but that should be his strory.
    Hope some of this was at least close to your question :roll:
  3. murray2paddles

    murray2paddles WindyNation Engineer

    Yes I have run it on one turbine at a time.
    Questionable on multi turbines, well if he sees this thread he can explain how many inverters he is rumning on the front end.
    "Front End= 10.8-30
  4. leamywind1

    leamywind1 WindyNation Engineer

    Hi guy's
    Regarding the MPPT tracking i have some information to share. As you know i have been studying and testing mulitple turbines using the Sun G wind GTI inverter as well as Murray doing single turbine testing. Let me be clear it is for the 500w 10-30v wind rated only. I have found variuos things going on. I can assure nothing going wrong at all.
    When using 4 turbines under 1 inverter the inverter seems to hold very true. MPPT is tracking as it should. Even if the volatge rises up to 15-20v it quickly pulls it back down quickly in the range of 11v-12v and it seems to be very happy. The MPPT does not seem to be confused to the point to be alarmed with at all. It does not get pushed into over volt until higher winds arrive. Which would be normal considering i am pushing higher amps, volts, and RPM's through it. I have seen about 400 ish watts doing it this way defore over volt off of 1 single inverter. Muarry can varify this as we exchange large amount of information and pictures of data daily, of course all on our time and dime.

    With two inverters and the same set up I have increased my watts from 400 before overvolt to 940 from my kW plug in meter readings. MPPT still seems to be absolutley fine. With the second inverter hooked up i also used battery clamping. This seems to work very well. The wattsview was showing 1050w at 46 amps but i beleive that was from the total load, 2 inverters and a 24v battery bank (2 12v batteries). The reason for the battery clamping is i do not have enough inverters yet to cover my maxium turbine production thus more of a load for higher winds and to keep over volt disconnect from occuring. I would rather put the extra power some where then burn it to a dump load resistor at that point. I have also seen the inverters hit 30v exackly and not disconnect. I beleive the battery clamping has assisted in that.

    When I hooked up just one turbine to one inverter I was hitting over volt like crazy. It seemed the MPPT could not keep up with the fast producition of volts-power-rpm's. The wattge was very low before over volt. As the other three turbines were still hooked to the other one inverter. I had no problems with over volt. I then put back the turbine with the others in paraelle as they are all wired including the inverters, hooked up the second inverter again and all was well. This was the only time I could confirm that the MPPT was not keeping up. It seems to me that the MPPT works just fine with muliple inverters and turbines. if I am missing out on a few watts no dig deal. You get what you pay for.

    I beleive it is the characteristic of each individual turbine that can cause over volt regarding how fast it can hit voltage and push through one single inverter. I can tell you that using multiple turbines if that is all you are able to use works great. I would recommend if using a 500 or 750w turbine to use 2 or more unless you can put up a 3kw bird or bigger and be done. I am very happy with the results I have received from the Sun G GTI as well as my turbines so far. I feel i am getting to the end of my quest for what I want regarding the size wind system i currently have as well as the GTI's i am using. On a final note all of this is pretty much right out of the box testing. No modifications needed. If you are buying a product that needs to be modified you may want to look else where. Is'nt our quest for free watts suppose to be free and not so costly?
    1.4kw solar
    2kw wind
    .................and still going
  5. leamywind1

    leamywind1 WindyNation Engineer

    No you do not need multiple turbines but possibly mutilpe inverters to work with regarding the sun G to keep the correct load on it. Each turibne is different so experimenting with the first inverter is key before prurchasing another. Unfortunaly it is all trial and error per turbine. Pretty simple for one turbine and one inverter or if you have to ad one more inverter still cost effictive instead of spending and wasting money on trying to modify.

    Using a 24v bat bank is done with a 40a blocking diode. Power can only flow into the battery in one direction, not out, but only in. The turbine or inverters cannot drain the batteries. There is no reason to do this wiring method for solar, only wind as far as i can see. If you want GTI and battery put in a switch to go back and forth. GTI and battery should not be mixed other then to clamp for the over volt for a turbine in my opion. Solar or wind to charge your batteries and solar or wind for GT.
    So think of the batteries as a releif valve. Since the inverters take 10-30v the power will only start to enter the batteries at 24v or what ever the battery voltage is 23-24-26 ect. I am fine with the 6 extra volts going to the batteries until I get two more 10-30v GTI. i will have 2000w GTI 10-30v. Right now I just hooked up another GTI at 22-60V and clamped at 36v. So I am running 10-30v w/ (2) 500w plus (1) 22-60 w/ 1 500w with battery clamaping at 36v for my overvolt protection to assist the 22-60 v for over volt protection This 22-60 sun G is for solar so i do not want to fry it. Experimenting only. What i am really looking for here is a combination of all three in the 22-30v range. After 30 volts then i will be actually losing power because the first (2) 10-30 will have disconnected. Been waiting for a month now for my new correct inverters to arrive so I can get rid of battery clamping altogether.
    I hear ya on the car PMA. Just junk and a total waste of money. i have two Wind Blows unfortuanly and I have to run two of them to get 20a out of them in 20MPH winds.

    Again I am not sure why you would be using a battery with a GTI. If so, your clamping must be higher then the input v 14-28 of the inverter of choice. Use a 24v battery clamping with a blocking diode, set it up for power to only enter the batteries. You could also use a charge controller set at 14 v to dump to a GTI but then you have an issue if the grid goes down. You can take it another step and install relay's and such but why. GTI for the grid and battery for em power only.
    As far as the tiny volatges and amps-watts that you may be concerned with overall they really are not that big of a deal at least to me. My best advice is to run them in paraelle and let them do their thing for $100-$200 a peice.

    FYI just hit 47 volts with 36v battery clamping-gotta go hook up the watssveiw and i need more
  6. Minnesota

    Minnesota WindyNation Engineer

    Gotcha. You just never mentioned what you did with the power you stored in the battery. That's what I was "missing."

    I think eventually one of these GTI companies will wise up and program one of these GTIs for the dynamics of wind as well as provide a leakless low voltage cut-in/off, and voltage clamping at the high-end rather than just disconnect. It would be nice if these 2 end points were a bit adjustable too. :D

    It is a lot of dicking around currently.

    The new Midnight Solar Classic charge controller has a wind setting and uses MPPT. That driving and managing a single 12V bank with a leakless 12V GTI connected in parallel might be the answer.
  7. murray2paddles

    murray2paddles WindyNation Engineer

    Sorry Mn. I missed the whole point of your question on the use of the batteries, just never hit me why anyone would be using the MPPT grid tie for battery storage use ! I do have a back up system off my grid ties so that when the grid power goes down then all incoming is directed to my bank.
    But I keep mine separated and let them do what they ate designed to do.

    We also have been pondering the fact that if you can have a range of 10.8-30 & 28-60, why are they not combined to eliminate that lower end Volt overload ?
    BUT, at the same time Larry and I have also learned by trial and error that we have really seen the efficiency and effectiveness of using the MPPT systems. We have also seen some variance in advertised ratings but not so much that it created major concerns with what we were testing.
    For us, the more efficient watts produced was keeping the turbine clamped to below the 30 V and building more amps. As he has already shared this has been done by using the battery bank ( as a clamp only) or adding more 10.8-30 inverters on the front end and the MPPT has worked great keeping low volt to eliminate overvolt and stay below the 30 range. As an example so far we have seen more watts being recorded using two 10.8-30 on the front end compared to allowing a 28-60 take over on it's own for the top end. I do not own the watts view for my monitoring but Larry does so somewhere in his data it is recorded for factual info.

    We have a new shipment of test inverters coming in from China and waiting impatiently for them to arrive to build on what we have learned so far ! ( I just melted another one on Friday, not a happy camper)
    Word of caution when ordering directly from China, beware of the Calendar, place your order well ahead of the Chinese New Year or you will wait, and wait and :lol:
  8. Minnesota

    Minnesota WindyNation Engineer

    The one thing we are fighting is that these GTIs are design for solar panels, and solar panels are current sources, not voltage sources. Batteries are also current sources (Relatively steady voltage but wide range of current capability).

    Turbines are voltage sources, and when the MPPT software of the GTI see this it says "WTF!" The games that are being played are to make the GTI still think it is dealing with a current source. It's like putting a dress and lipstick on Larry ... it's still Larry. :lol:

    Another guy I have been corresponding with is trying to do the same thing you guys are doing. He saw twice the watts going to a battery bank alone vs the same turbine in the same wind being managed by a 300w PJ GTI. He had a switch to toggle between the 2 configurations. This suggest some nasty tradeoffs using these solar GTIs.

    I did hear today that Morningstar is working on a MPPT wind charge controller. They do have $199 MPPT solar controller so that would be cool if they had one for wind, then GTI of off the bank as I suggested earlier.
  9. murray2paddles

    murray2paddles WindyNation Engineer

    Now I am more confused than I normally am ! :roll:

    Are you saying when the manufacturer is advertising that there is a solar model and a wind model inverter that they are misleading us when if fact they are all for solar only?

    All the ones I have bought were rated for wind only !

    I suppose there are many of us out there testing in our own ways and I am sure there wil be a variety of success's for each type of set-up and types of wind coditions and style of turbine you are using.......But when my wind type Sun 500 inverter can give me high 400's watts in mid to high 20's mph winds on a WN 500, you are not going to hear any complaints from this guy!
    The inverter that went faulty on me the other day was completely all my fault from incorrect use :shock:
  10. leamywind1

    leamywind1 WindyNation Engineer

    Hey Mn,
    The extra power going into the batteries, well lets just say that they have not been charged up yet from doing it that way yet. If they were to get to a higher range I can tie them to a charge controller then to a dump resistior of some sort. The GTI"s keep it clamped pretty darn good so I do not see that 24v power go in to them to much. 95% of the volatge is in the 11-20v ranges with the Sun G wind rated GTI.

    As far as all of these China inverters being rated for sun or wind or both. I guess you could some it up as if your are savoy enogh either one will work with wind. My choice will be the Sun G that disconnecs whick would catogorizes them to be more for wind in my opinion because of the over volt disconnecting control they have. I have also reconfirmed from yesturdays experiments that the "wind rated" Sun G inverters do convert the wind energy way quicker then a reg. Sun G "solar" GTI. The voltage was running 5-10v higher before the "solar inverter" would start converting watts.
    This may also be why "the other guy" from your last post maybe seeing a loss of watts when switching over from battery to GTI. I think if you asked him to try a Sun G wind rated he will see a big difference and better results.
    It is good to hear that someone else is doing these experiments and helping us answer questions.
    Hope this helps
  11. Minnesota

    Minnesota WindyNation Engineer

    That is very interesting Larry. Is there an active ad for the SUN 500G for wind? The person I mentioned is using a power jack which is a solar unit.

    Love to see a video of a turbine on this wind GTI and then switched over to a solar GTI in the same wind with an anemometer in view. Also, perhaps a wattsview plot to compare the turbine V/A with each GTI type.
  12. murray2paddles

    murray2paddles WindyNation Engineer

    Mn. Is your response to Larry an answer to my question as well ? Did you not know we were using WIND rated sun inverters ?
    OR, are you just stating they are all for solar and not suited for wind ?
  13. Minnesota

    Minnesota WindyNation Engineer

    I guess both. Many of these Chinese GTIs are agnostic as they don't really restrict what you can connect to them. I was essentially assuming, based on my experience with the Power Jack 300 and the SUN-250G with solar panles, that they are essentially programmed for the slow behavior of solar, but can be used with a wind turbine but less effectively and with restrictions on voltage range. Yes I know the dump-load capable one Larry found might accomodate a turbine a bit more conveniently but at the core I assumed it was not any different. I am learning by his post that he thinks the programming at least is different on certain ones allowing better tracking with a wind turbine.
  14. murray2paddles

    murray2paddles WindyNation Engineer

    Yes I suppose they are better equipped for wind and the ads are quite clear that is where they are too be used.
    Both Larry and I test the same models but in different wind settings and amount of turbines.

    As I shared in a previous post, when I am getting high 400's using this inverter on one WN 500 in mid to high 20's wind, I really do not .know why anyone would not be interested in this combination or how they can be claimed as an inferior product.
    In the very high 490's it will go to over volt or too dump which ever you choose. When going to over volt I will use a higher V inverter to take over. We also know that by doubling up on the inverters you can keep continous watt production without the need if a safety dump or forcing it into v overload. This is were you are also able to start including multiple turbines if you wish or if your place of residence will allow it.

    Right now because this is all real time testing we do I would not hesitate to recommend this wind rated Sun grid tie inverter to anyone using a Windy Nation or WindMax turbine.

    For recorded info Larry has this on file through the use of his watts view.
    Hope this has cleared up any misunderstandings about our testing results and the products we are using . :ugeek:
  15. Hi, MPPT for wind are hard to find. I am looking for one I can afford. I hope this helps.

  16. timber

    timber WindyNation Engineer

    Great video Minnesota and thanks for the links to the others Lauri.
    It's great to see the combined efforts of all here to understand and come up with better ways to get the most from wind and solar.
    Great job guys!
  17. windyguru

    windyguru WindyNation Expert

    Rumor has it ... well I should say that it is more than a rumor, that Morningstar has wind MPPT charge controllers in the real world testing phase. :)
  18. timber

    timber WindyNation Engineer

    Well that's good news, I hope it's priced somewhere in the same range as their solar unit(s). If so, this would be a nice option to have available.
  19. windyguru

    windyguru WindyNation Expert

    From what I know, they are re-designing their Solar MPPT firmware to work with wind. I too would hope that the retail price is in the $400 area.
  20. Hi, just posting a very nice video example that shows the potential that adding a MPPT controller will have for a wind turbine.

    At this time there is only one US manufacture that I have been able to find.

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