Connecting a 48V turbine through solar Xantrex MPPT60-150

vomusvomus Solar Expert Posts: 31
Hi!
I was wondering whether anyone connected a 48V wind turbine to batteries through Xantrex60-150 charging controller. The manual says that MPPT60-150 does not necessarily work with the panels but can work with any DC sources as long as they are below 140 VDC.

Having such a setup seems to be beneficial because this way wind power source also gets controlled through a Xanbus and MPPT could regulate its DC output not only to maintain a normal charging process but also taking a load into account eliminating the need for a dump load. Without an MPPT controller I'd have to set a Grid Support Volts 0.5 V below a floating voltage of a wind turbine controller (at least, this is what a Xantrex manual says) and it might not provide a full charge cycle.

Can anyone share an opinion on the subject?

Comments

  • BB.BB. Super Moderators, Administrators Posts: 29,229 admin
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150

    An MPPT charge controller can give you more power from the turbine by better matching the I*V curve of the alternator to the (more or less) fixed voltage of the battery bank.

    Some issues that would concern me:
    1. What is the ultimate voltage of your 48 volt turbine--It probably can easily exceed 100 VDC, and possibly 150 VDC--That would damage your MPPT controller when the battery bank was full.
    2. What would your Turbine do if electrically unloaded in high winds. Most Horizontal Axis Wind Turbines (HAWT) will over speed and self destruct in medium to high winds if there is no electrical loading--That is the reason for dump loads. To keep the turbine loaded and not over charge the battery bank.
    3. Yes, you can use a Hybrid Inverter (GT and Off Grid mode) to dump AC power to the utility--However, you would probably still need a separate dump load + controller if the AC power "goes away" for safety (in the US, we are technically supposed to have two dump loads/methods of controlling over charging/turbine speed if one of them fails).
    4. I don't know anything about how the MPPT controller will work with your turbine... A MPPT controller designed to work with a wind/water turbine will have a programed I*V vs RPM curve programmed into the controller (like the Midnite Classic) to ensure the two will play well together. I just do not know enough about your system/Schneider MPPT controller to give you an answer if it will work or not. As long as the turbine does not over voltage in the MPPT controller input--It should not hurt anything to try.
    Your thoughts?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    BB. wrote: »
    An MPPT charge controller can give you more power from the turbine by better matching the I*V curve of the alternator to the (more or less) fixed voltage of the battery bank.

    Some issues that would concern me:
      ...
    1. I don't know anything about how the MPPT controller will work with your turbine... A MPPT controller designed to work with a wind/water turbine will have a programed I*V vs RPM curve programmed into the controller (like the Midnite Classic) to ensure the two will play well together. I just do not know enough about your system/Schneider MPPT controller to give you an answer if it will work or not. As long as the turbine does not over voltage in the MPPT controller input--It should not hurt anything to try.
    Your thoughts?

    -Bill
    The rub, as you suspect, is that an MPPT algorithm designed for a current limited power source with instantaneous current and voltage response with no time constant will not work well with a primarily voltage driven generator or alternator output, especially when you have to consider the dynamic flywheel effect of the power source.
    If you make a sudden increase in the load current on a wind or heavy water turbine, the voltage will not drop significantly but the turbine will start to slow down and make take seconds or more to reach a new equilibrium speed with a lower voltage (and therefore lower power) than was apparently available immediately.

    The result is that the MPPT controller looking at a battery source needs to know what the maximum safe current is and not try to sweep past that point.
    And the MPPT controller looking at a turbine source with flywheel effect either needs to just look at the instant unloaded voltage to determine speed and set the corresponding current point based on that (Midnite Solar) or else do a very slow sweep and at the same time ignore fluctuations caused by wind speed variations.

    An MPPT controller looking at a solar panel string with rapidly varying shade conditions, like tree branches in the wind or very low small clouds in a high wind, would have similar problems
    SMA SB 3000, old BP panels.
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    BB. wrote: »
    An MPPT charge controller can give you more power from the turbine by better matching the I*V curve of the alternator to the (more or less) fixed voltage of the battery bank.

    Some issues that would concern me:
    1. What is the ultimate voltage of your 48 volt turbine--It probably can easily exceed 100 VDC, and possibly 150 VDC--That would damage your MPPT controller when the battery bank was full.
    2. What would your Turbine do if electrically unloaded in high winds. Most Horizontal Axis Wind Turbines (HAWT) will over speed and self destruct in medium to high winds if there is no electrical loading--That is the reason for dump loads. To keep the turbine loaded and not over charge the battery bank.
    3. Yes, you can use a Hybrid Inverter (GT and Off Grid mode) to dump AC power to the utility--However, you would probably still need a separate dump load + controller if the AC power "goes away" for safety (in the US, we are technically supposed to have two dump loads/methods of controlling over charging/turbine speed if one of them fails).
    4. I don't know anything about how the MPPT controller will work with your turbine... A MPPT controller designed to work with a wind/water turbine will have a programed I*V vs RPM curve programmed into the controller (like the Midnite Classic) to ensure the two will play well together. I just do not know enough about your system/Schneider MPPT controller to give you an answer if it will work or not. As long as the turbine does not over voltage in the MPPT controller input--It should not hurt anything to try.
    Your thoughts?

    -Bill

    I am not planning to plug a turbine DIRECTLY to MPPT! That would probably be really bad. The turbine has its own controller with I suspect all the power versus RPM programmed. The wind controller outputs a 48DC ready to plug to the battery bank, so the first and the third of your questions should be addressed by this.

    The second question about the dump load... I actually do not exactly know how it will work. I asked my local Schneider support and they told me that MPPT60-150 regulates its output not only based on whatever batteries want but also based on whatever a final load is (coming out of my XW4548 ). It actually makes sense because there is a Xanbus between the devices and I myself experimented with different loads looking at what MPPT outputs. It really increases power when I plug additional load provided of course I have enough Sun.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »
    The second question about the dump load... I actually do not exactly know how it will work. I asked my local Schneider support and they told me that MPPT60-150 regulates its output not only based on whatever batteries want but also based on whatever a final load is (coming out of my XW4548 ). It actually makes sense because there is a Xanbus between the devices and I myself experimented with different loads looking at what MPPT outputs. It really increases power when I plug additional load provided of course I have enough Sun.
    The feature of the Schneider equipment that increases DC output when the batteries are full but there are direct DC or inverter driven loads will allow you to work with a dump load, but will not control the dump load itself.

    A safety dump load for a wind turbine must kick in without any intervention on your part whenever your CC and equipment loads are not pulling enough power from the turbine to hold it down to a safe speed. This may or may not be a feature of your upstream wind controller.
    Having to plug in extra loads when the wind gusts, or when you turn the CC off suddenly, is not going to save your turbine.
    Midnite Solar uses a separate box called the Clipper which is located ahead of the CC and clips (of course) the output by throwing in a resistive load bank (or whatever else you choose) whenever the voltage from the turbine reaches a settable limit, independent of what the CC is doing at the same time.

    To avoid a misleading assumption that the Classic in wind mode uses the same MPPT algorithm that it uses for PV, I would rather call it PPTP for programmable power point tracking, since it will maximize the power taken from the turbine long term, but does not do that by sweeping the instantaneous power.
    Until you tune the lookup table of current versus voltage to match your turbine, the varying effective load resistance will be OK, but not as good as with a lookup curve just for the particular turbine.
    Once that is done, though, it will pull the optimum power over the full range of wind conditions.
    SMA SB 3000, old BP panels.
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    inetdog wrote: »
    The rub, as you suspect, is that an MPPT algorithm designed for a current limited power source with instantaneous current and voltage response with no time constant will not work well with a primarily voltage driven generator or alternator output, especially when you have to consider the dynamic flywheel effect of the power source.
    If you make a sudden increase in the load current on a wind or heavy water turbine, the voltage will not drop significantly but the turbine will start to slow down and make take seconds or more to reach a new equilibrium speed with a lower voltage (and therefore lower power) than was apparently available immediately.

    The result is that the MPPT controller looking at a battery source needs to know what the maximum safe current is and not try to sweep past that point.
    And the MPPT controller looking at a turbine source with flywheel effect either needs to just look at the instant unloaded voltage to determine speed and set the corresponding current point based on that (Midnite Solar) or else do a very slow sweep and at the same time ignore fluctuations caused by wind speed variations.

    An MPPT controller looking at a solar panel string with rapidly varying shade conditions, like tree branches in the wind or very low small clouds in a high wind, would have similar problems

    Well, this reasoning would be true if I plugged a turbine to an MPPT DIRECTLY but I am not going to as I mentioned in a previous post: there will be a wind turbine controller in between. This should provide a stabilized voltage. Besides my turbine is vertical which means the rotation should also be more steady, I believe. Am I right?
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »
    Well, this reasoning would be true if I plugged a turbine to an MPPT DIRECTLY but I am not going to as I mentioned in a previous post: there will be a wind turbine controller in between. This should provide a stabilized voltage. Besides my turbine is vertical which means the rotation should also be more steady, I believe. Am I right?
    First, yes, as long as the wind controller itself is fitted with a dump load. And there could be a different problem if the wind controller is a PWM voltage controlled output. The MPPT circuitry will not like that at all.
    Second, no. The vertical axis wind turbine will deal a bit more gracefully with varying wind directions, but will not do any better (or even as good) with turbulent air and will tend to have a lower output for the same swept area than a conventional horizontal axis turbine. Look up the literature on actual tests of vertical axis and combine that with the unfortunate tendency to mount verticals on much shorter towers because of the tipping force on the top of the tower and the mistaken belief that they work better in turbulent air.

    They have been shown to make excellent public art projects though. :)
    SMA SB 3000, old BP panels.
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    inetdog wrote: »
    The feature of the Schneider equipment that increases DC output when the batteries are full but there are direct DC or inverter driven loads will allow you to work with a dump load, but will not control the dump load itself.

    A safety dump load for a wind turbine must kick in without any intervention on your part whenever your CC and equipment loads are not pulling enough power from the turbine to hold it down to a safe speed. This may or may not be a feature of your upstream wind controller.
    My wind controller is a simple one. It does not have dump load mains in it. But my idea of plugging a wind turbide (+ its controller) through MPPT60-150 was to control charging in what seems to be a better way.
    Having to plug in extra loads when the wind gusts, or when you turn the CC off suddenly, is not going to save your turbine.
    Midnite Solar uses a separate box called the Clipper which is located ahead of the CC and clips (of course) the output by throwing in a resistive load bank (or whatever else you choose) whenever the voltage from the turbine reaches a settable limit, independent of what the CC is doing at the same time.

    To avoid a misleading assumption that the Classic in wind mode uses the same MPPT algorithm that it uses for PV, I would rather call it PPTP for programmable power point tracking, since it will maximize the power taken from the turbine long term, but does not do that by sweeping the instantaneous power.
    Until you tune the lookup table of current versus voltage to match your turbine, the varying effective load resistance will be OK, but not as good as with a lookup curve just for the particular turbine.
    Once that is done, though, it will pull the optimum power over the full range of wind conditions.
    What is a "lookup table"? It might be a dumb question but...
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »
    What is a "lookup table"? It might be a dumb question but...
    Not a dumb question at all. It is a common phrase in computer and microcontroller programing, but I forget that it is not as common in everyday speech.
    Basically it is a table of pairs of numbers in which the value of the first number is used to look up the corresponding value of a second number.
    In this particular case, it is a table which specifies for each value of the open circuit voltage what amount of current the MPPT device should pull to get the maximum power from the turbine.
    In between actual voltage values in the table, the controller can either interpolate (if you do not not understand that, don't worry) or just take the nearest voltage entry and use the corresponding current.
    SMA SB 3000, old BP panels.
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    inetdog wrote: »
    Not a dumb question at all. It is a common phrase in computer and microcontroller programing, but I forget that it is not as common in everyday speech.
    Basically it is a table of pairs of numbers in which the value of the first number is used to look up the corresponding value of a second number.
    In this particular case, it is a table which specifies for each value of the open circuit voltage what amount of current the MPPT device should pull to get the maximum power from the turbine.
    In between actual voltage values in the table, the controller can either interpolate (if you do not not understand that, don't worry) or just take the nearest voltage entry and use the corresponding current.

    I do understand what an interpolation is. Speaking of the lookup table I also understand what it means in general but I did not understand how it is applicable in this case. Basically when you say "lookup table" you mean a "digitized" I-V curve in a MPPT algorithm.

    Coming back to a wind application... I could simply turn off MPPT in the charge controller and set a reference point to whatever a wind controller outputs. It might not always by an ideal output in terms of power but it will provide charging. Do I understand this correctly?
  • BB.BB. Super Moderators, Administrators Posts: 29,229 admin
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150

    Some MPPT controllers do have a "set input voltage" -- It technically only turns off the "tracking" and sets the "optimum voltage" you expect on the Vpanel input to the controller.

    I am a little confused about the Wind Turbine/Controller side--Do you have a link to the system or components you want to use?

    VAWT do tend to not over speed if unloaded--So it should survive feeding a MPPT (or PWM) charge controller (battery charge controller reduces current/power needed from the wind system; wind system will either speed up--Safely--And/or your wind controller will dump/apply brakes/other?).

    There can be issues with placing several controllers in series... Many, for example, require a valid voltage on their "battery charging" terminals to wake up. If there is no battery voltage, it may stay asleep--And if there is too much voltage, the controller may jump between 12/24/48 volt default operating/charging voltage.

    And other issues--As inetdog talks about--There are feedback systems in the MPPT charge controllers--That can cause a "ringing" condition between the various components. May appear as varying turbine speed (sort of like a new car driver is driving with lots of jerking because of excessive/poor timing of brake/throttle application, wildly swinging voltages between the Wind and MPPT controllers, etc..

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »
    I do understand what an interpolation is. Speaking of the lookup table I also understand what it means in general but I did not understand how it is applicable in this case. Basically when you say "lookup table" you mean a "digitized" I-V curve in a MPPT algorithm.

    Coming back to a wind application... I could simply turn off MPPT in the charge controller and set a reference point to whatever a wind controller outputs. It might not always by an ideal output in terms of power but it will provide charging. Do I understand this correctly?
    What I mean, exactly, is that instead of varying the current drawn (sweeping) over a wide range of current and voltage points, as an MPPT CC would do when dealing with PV input, the CC will just turn off the loads for a fraction of a second to read the open circuit output from the turbine. That (without a separate controller in the way) will tell you exactly what the turbine speed is. From that number, the CC will see what point it should be at on the I-V curve for that speed and then start to draw that current. If the process is just starting up, the turbine may slow down at that point as the CC starts to draw power. And the Voc will go down, causing a new point on the I-V curve to be selected. This will converge fairly quickly to the turbine running at a constant speed with the CC taking all of the available power the turbine can produce at that rotational speed.


    It is a different process than a "normal" MPPT algorithm, but it makes use of the ability of the MPPT input circuit to draw a controlled varying amount of current at any given voltage, unlike a resistive load.

    Both the current draw and the operating voltage at the input will vary as the wind speed and therefore maximum power turbine speed vary.
    SMA SB 3000, old BP panels.
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    inetdog wrote: »
    What I mean, exactly, is that instead of varying the current drawn (sweeping) over a wide range of current and voltage points, as an MPPT CC would do when dealing with PV input, the CC will just turn off the loads for a fraction of a second to read the open circuit output from the turbine. That (without a separate controller in the way) will tell you exactly what the turbine speed is. From that number, the CC will see what point it should be at on the I-V curve for that speed and then start to draw that current. If the process is just starting up, the turbine may slow down at that point as the CC starts to draw power. And the Voc will go down, causing a new point on the I-V curve to be selected. This will converge fairly quickly to the turbine running at a constant speed with the CC taking all of the available power the turbine can produce at that rotational speed.
    I understand this but it seems that this whole reasoning is applicable only if I plugged the turbine DIRECTLY to a solar MPPT controller. Well, not directly, because I would need at least for diods to make some kind of DC coming out. I however am planning to plug the output of a wind controller to the input of a solar MPPT controller. The whole process of stabilization of rotation that you describe will occur in the wind controller. Solar MPPT60-150 will get a "clean" 48 VDC. Am I right?
  • BB.BB. Super Moderators, Administrators Posts: 29,229 admin
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150

    Well--Not really.

    First, if you have a 48 volt battery bank, the MPPT charge controller will need ~60 VDC minimum on the input to output ~58 volts or so to charge the battery bank.

    99% of the MPPT charge controllers out there are "Down Converters" (buck mode switching power supply)--So the input voltage needs to be Vbatt+a couple of volts minimum to operate correctly.

    Next, the way a MPPT charge controller with a "fixed" tracking voltage would work (call it Vset for our discussion)... You pick 65 volts (or anything between ~60 volts and 149 VDC). The charge controller (my guesses) will look at the input voltage. If the voltage is below Vset, then the controller will take zero amps from the turbine (after the rectifier).

    As the voltage rises to Vset--The controller will start drawing current from the turbine--If the voltage goes below Vset, it will cut back on current. As the turbine voltage rises above Vset, the MPPT controller will take more current--All in the attempt to keep the Vinput voltage around Vset.

    With some limits. If the Ibatt exceeds 60 Amps, the MPPT controller will cut back on current from the turbine and the input voltage will now be at a different point in the IV curve (higher than Vset).

    Another limit--The MPPT controller will only output maximum available power/current into the battery bank in "bulk mode". Once Vbatt rises to ~58 volts (Absorb Voltage), then the MPPT controller will again cut back on input current from the Turbine... And again a new IV curve operating point that is higher than Vset.

    How fast will the MPPT controller "correct", how fast (and what does the) Turbine controller will respond, and even the momentum of the rotating machinery, damping coefficients in the MPPT and other "parts" of the system may affect how "stable" the whole system runs.

    Ever ride in a car where the driver instead of staying at 45 MPH instead seems to accelerate to 50 MPH, then slow down to 40 MPH, and back to 50 MPH? You can have similar things happen (over many seconds, or even fractions of a second)--Depending on the feed back loop characteristics of the "system".

    Control theory is very interesting--But becomes very heavy math very quickly.

    "Daisy Chaining" several controllers with incompatible control loop characteristics can give you unpredictable results. Or can work just fine.

    What type of wind controller are you using? Brand/model/link? I would be a little surprised if it would "be happy"with its output connected to the input of an MPPT charge controller.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    BB. wrote: »
    Well--Not really.

    First, if you have a 48 volt battery bank, the MPPT charge controller will need ~60 VDC minimum on the input to output ~58 volts or so to charge the battery bank.

    99% of the MPPT charge controllers out there are "Down Converters" (buck mode switching power supply)--So the input voltage needs to be Vbatt+a couple of volts minimum to operate correctly.

    This is something I'd have to look at. The manual says that the floating voltage is 58V.
    Next, the way a MPPT charge controller with a "fixed" tracking voltage would work (call it Vset for our discussion)... You pick 65 volts (or anything between ~60 volts and 149 VDC). The charge controller (my guesses) will look at the input voltage. If the voltage is below Vset, then the controller will take zero amps from the turbine (after the rectifier).
    By the way, does an MPPT-controller pick this Vset "randomly" and then converges to a value it dances around or one has to tell it this value? In Xantrex I see that MPPT may be either auto or manual. Is this what it means?
    As the voltage rises to Vset--The controller will start drawing current from the turbine--If the voltage goes below Vset, it will cut back on current. As the turbine voltage rises above Vset, the MPPT controller will take more current--All in the attempt to keep the Vinput voltage around Vset.

    With some limits. If the Ibatt exceeds 60 Amps, the MPPT controller will cut back on current from the turbine and the input voltage will now be at a different point in the IV curve (higher than Vset).

    Another limit--The MPPT controller will only output maximum available power/current into the battery bank in "bulk mode". Once Vbatt rises to ~58 volts (Absorb Voltage), then the MPPT controller will again cut back on input current from the Turbine... And again a new IV curve operating point that is higher than Vset.

    How fast will the MPPT controller "correct", how fast (and what does the) Turbine controller will respond, and even the momentum of the rotating machinery, damping coefficients in the MPPT and other "parts" of the system may affect how "stable" the whole system runs.

    Ever ride in a car where the driver instead of staying at 45 MPH instead seems to accelerate to 50 MPH, then slow down to 40 MPH, and back to 50 MPH? You can have similar things happen (over many seconds, or even fractions of a second)--Depending on the feed back loop characteristics of the "system".

    Control theory is very interesting--But becomes very heavy math very quickly.

    "Daisy Chaining" several controllers with incompatible control loop characteristics can give you unpredictable results. Or can work just fine.
    Is there any way to see that such a current/voltage pendulum is occuring in the system?
    What type of wind controller are you using? Brand/model/link? I would be a little surprised if it would "be happy"with its output connected to the input of an MPPT charge controller.

    -Bill

    Well... The make is unknown because it was brought directly from a Chineese factory. As it usually happens, one can stick any label onto it. It says a model of WWS10-48-N00 on it and is supposed to provide 1kW for a 48V battery bank. The floating voltage is Vbat * 14.5/12 which gives 58 as I said above. It does not have dump load mains and this is what scares me. I could plug its DC output directly to batteries but will not be able to regulate the charge process. This is the reason I thought about chaining to controllers.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »

    Well... The make is unknown because it was brought directly from a Chineese factory. As it usually happens, one can stick any label onto it. It says a model of WWS10-48-N00 on it and is supposed to provide 1kW for a 48V battery bank. The floating voltage is Vbat * 14.5/12 which gives 58 as I said above. It does not have dump load mains and this is what scares me. I could plug its DC output directly to batteries but will not be able to regulate the charge process. This is the reason I thought about chaining to controllers.
    It may be intended to be connected directly to the batteries with the addition of a shunt mode (dump type) charge controller to protect the batteries.
    You rarely see shunt mode CCs these days, but this situation would be one use for them.
    SMA SB 3000, old BP panels.
  • BB.BB. Super Moderators, Administrators Posts: 29,229 admin
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150

    Is it this one?

    Attachment not found.

    http://www.ttnet.net/ttnet/gotoprd/EN300/030/0/251303234303130323.htm
    TECHNICAL PARAMETERS:
    Product Model WWS10-48-N00
    Rated Battery Voltage 48V
    Rated Wind Turbine Input Power 1kW
    Maximum Wind Turbine Input Power 1.5kW
    Wind Turbine Brake Current 21A
    Rated Solar Input Power 300W(Adjustable)
    Floating Charging Voltage 58V
    Display Mode LCD
    Quiescent Current ≦20mA
    Ambient Temperature & Humidity -20~+55℃/35~85%RH(Without Condensation)
    Communication Mode (Optional) RS232、RS485、RJ45、GPRS (optional)
    Temperature Compensation Function (Optional) -4mV/℃/2V ,–35℃--+80℃ ,Precision:±1℃
    Dimension(L x W x H) 445×425×170mm
    Net Weight 11kg
    Data for Low Voltage Charge Function
    Wind Turbine Start Charge Voltage 8V
    Input Admittance Value 10/60
    Dimension(L x W x H) Controller Box: 440×300×170mm
    Dumpload Box: 300×190×120mm
    Net Weight Controller: 7.5kg ; Dumpload Box: 3.5kg

    OK--Looks like a "Dump/Shunt/Diversion" type controller... It monitors the battery bus voltage and when the setpoint is reached, it applies a resistive dump load to the 3 phase side of the wind turbine's Alternator output.

    This controller, I believe is designed to connect directly to the battery bank. It will not work correctly if the Vbatt terminals are connected to another (series) charge controller. First, the MPPT controller does not supply voltage to "run" the wind turbine charge controller. Second, the MPPT (or any series charge controller) would need >Vbatt-charging+a couple of volts (say 60-64 volts minimum) to charge the battery bank themselves... Which the Wind turbine would "shut down" the turbine because of "battery full/over voltage".

    What might help you to understand how an off grid power system works--The battery bank is really the voltage regulator (holds bus voltage between ~42 volts to ~60 volts extreme nominal range). If/when the voltage exceeds a programed value, the charge controller (no matter which type) will "gracefully" figure out how to limit/turn off charging current to the battery bank.

    These controller do not have "voltage regulated" output. They are not like a DC bench top power supply that will supply 58.50 volts no matter what the loads are on the power supply.

    These guys, if you disconnect the battery bank will either shut down, or over voltage the output (go>72 VDC or more) -- They do not have the internal logic/control loop to output a steady state voltage (just like your car, if you disconnect the battery when the alternator / engine is running, the alternator will output upwards of 100 VDC to your car's electrical system and fry the lights and electronics without the battery connected).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vomusvomus Solar Expert Posts: 31
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    BB. wrote: »
    Is it this one?
    Yep. Looks like this one.
    OK--Looks like a "Dump/Shunt/Diversion" type controller... It monitors the battery bus voltage and when the setpoint is reached, it applies a resistive dump load to the 3 phase side of the wind turbine's Alternator output.

    This controller, I believe is designed to connect directly to the battery bank. It will not work correctly if the Vbatt terminals are connected to another (series) charge controller. First, the MPPT controller does not supply voltage to "run" the wind turbine charge controller. Second, the MPPT (or any series charge controller) would need >Vbatt-charging+a couple of volts (say 60-64 volts minimum) to charge the battery bank themselves... Which the Wind turbine would "shut down" the turbine because of "battery full/over voltage".
    Well... this thought of not being able to run the wind controller THROUGH the MPPT was sitting in the back of my head all the time. :-( The second is something I did not realize. Thank you.

    What might help you to understand how an off grid power system works--The battery bank is really the voltage regulator (holds bus voltage between ~42 volts to ~60 volts extreme nominal range). If/when the voltage exceeds a programed value, the charge controller (no matter which type) will "gracefully" figure out how to limit/turn off charging current to the battery bank.

    These controller do not have "voltage regulated" output. They are not like a DC bench top power supply that will supply 58.50 volts no matter what the loads are on the power supply.

    These guys, if you disconnect the battery bank will either shut down, or over voltage the output (go>72 VDC or more) -- They do not have the internal logic/control loop to output a steady state voltage (just like your car, if you disconnect the battery when the alternator / engine is running, the alternator will output upwards of 100 VDC to your car's electrical system and fry the lights and electronics without the battery connected).

    Then my last question comes to this. I believe this particular type has no dump load mains. What will then this wind controller do if the battery is charged and there is no dump load? Simply turn off the DC coming to batteries? I'd guess it would depend on what my XW4548 does at this point. If it is configured to Grid-support, the excess DC should go directly to be converted to AC. What happens when there is not enough AC load to swallow all this extra DC? If it were an MPPT only system, the MPPT would regulate the output. But how will it work here?
  • BB.BB. Super Moderators, Administrators Posts: 29,229 admin
    Re: Connecting a 48V turbine through solar Xantrex MPPT60-150
    vomus wrote: »
    Then my last question comes to this. I believe this particular type has no dump load mains. What will then this wind controller do if the battery is charged and there is no dump load? Simply turn off the DC coming to batteries? I'd guess it would depend on what my XW4548 does at this point. If it is configured to Grid-support, the excess DC should go directly to be converted to AC. What happens when there is not enough AC load to swallow all this extra DC? If it were an MPPT only system, the MPPT would regulate the output. But how will it work here?

    Guessing, but from the limited information available--The shunt controller puts a 3 phase relay directly on the Alternator output. And then the main current path is continued through the rectifier to the battery bank. And the controller monitors the battery bank voltage.

    When the battery bank is "full", the controller turns on the 3 phase relay to a module with three sets of power resistors. The three resistors will basically "over load" the turbine alternator and cause the turbine to slow down to a near stop (because the torque of the alternator exceeds the torque of the blades). Because the resistors+relay are on the thee phase side of the circuit, the battery bank is "unloaded" and only the turbine sees the (3 phase AC) resistor load bank.
    Whether the wind turbine is three phase AC output, single phase DC output or single phase AC output
    Dimension(L x W x H) Controller Box: 440×300×170mm
    Dumpload Box: 300×190×120mm
    Net Weight Controller: 7.5kg ;
    Dumpload Box: 3.5kg

    Actually a cute design... The controller only needs to dump power from the turbine--which should be a lot less because it is "stalling" out the wind turbine--Instead of having to manage the constant current from the battery bank plus operating wind turbine. Also, does not "micro cycle" the battery bank (discharge battery bank, then stop dump load, battery bank is recharged for a few seconds/minutes, then turns on dump load to battery bank again, repeat).

    The shunt controller directly on the turbine then manages only the turbine excess charging energy--So you need one dump controller per wind turbine--Instead of a single larger dump controller (or more) per battery bank with multiple charging sources.

    Remember, I am guessing based on the limited data sheet information in the link.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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