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Hai... I need some solution... I'm not a electrical engineering... so, there are 5 unit of 3 phase wind turbine, with rate output up to 2Kw, 48V each... and I need to produce current load for home about 7Kw to 9Kw, 240V,,, so, how to wiring from 5 unit of wind turbine to home current...

sorry for my english and thank you...



9 days ago

An issue that I know a bit about, is that most wind turbines generate about 50% more kWh's per year, if controlled properly with an MPPT controller. An MPPT (multi power point tracking) controller is a computer controlled switch for the turbines alternator, and it can connect and disconnect the turbine alternator very quickly, many times per second. Being able to turn off the alternator some of the time makes for less load on the turbine, allowing it to run faster than it would have with the full load of the alternator. The turbine will now collect more Watts because of the blade speed can be matched more closely to the wind speed. There arn't many good small MPPT controllers anymore, but these are among the least expensive
These controllers need DC input, so each turbine needs a rectifier, and generally, each turbine should also have a shut down switch which disconnects the alternator from the output lines, and shorts the 3 phase windings to each other, to stop the turbine.

Then the issue is if you connect multiple DC inputs to your inverter, all with different voltages, what's going to happen! I doubt it's good but I'm not sure. As I understand it, if you connect them all to a battery, only the highest voltage one will work in theory, but in reality, any connected DC output will be pulled down to match the battery voltage, so as long as the output from the rectifier is above the battery voltage, then you should be able to connect them all together in parallel. I don't know if an inverter can act like a battery in providing a big "sink" to pull all the voltages to its level.


Reply 9 days ago

These fancy controllers are good for solar use but not really useful for old school generators without any electronics.
And in a multi generator configuration as the author needs it far too costly as well.
You can not generate more power but shutting the feed off either.
A good generator runs at a fixed speed - the speed suited for the design.
The simple approach here is to adjust the turbine blades but that is not really feasable on a hobby level.
Most, if not all hobby wind generators will be subject to speed changes depending on the wind speed.
That is why chrge controllers, like used in car alternators come so handy: You can power the rotor coil from the outside without the rectifier and controller of the alternator.
With a suitable external controller you can then keep the output voltage constant to the need by a simple feedback system.
I had otherwise unmodified car alternators delivering anything between 6 and close to 40V just with external feedback for the rotor coil.


4 months ago

how about wiring like a diagram... can turbine produce about 6kw to 8.5kw, 240v home... thank

Turbine Battery Diagram.JPG

Reply 2 months ago

individual charge controllers would be much better, the amperage will be limited by the slowest turbine if used in series.


4 months ago

My Calculation? right or wrong


4 months ago

A thing people often forget is that a rectifier is also sort of an isolator.
Whatever comes out of your rectifiers can not really go back into another one due to the polarity of the diodes.
The real problem starts with the load on the system.

The big wind turbines work by providing a syncronised and matching AC voltage to the grid.
So the load requirements can be neglected as it is designed to be a one way system anyway.
In your case however it would mean that under enough load some generators will struggle.
Imagine you are drawing about 5kW.
Means ideally each generator would supply a bit of 1kW.
Any generator running lower than that will get a far greater load until the overall demand is low enough again.
I was thinking for about 4 hours to come with a quick and simple solution - something I usually don't for a reply here...
But then it really hit me hard!
There is a dirt simple but slightly costly solution to your problem!

Since you are running a 48V supply system you can use solar charge controllers after each rectifier!
These only allow a current draw that the source can handle.
So if one generator is happy to provide 2kW, one 1.5kW and the rest just 800w, then these solar charge controllers will spread the load so each generator is running without overload conditions.
The simple models have a fixed setup, the more expensive models can be bought with an adjustable input current limit.
Makes a lot of sense if you create your own solar system and want to go cheap on the panels then these controllers set the limits that are otherwise regulated directly within the panels.
Ebay can provide you with some chinese models at low cost to try.
Only downside is that you require 50amp controllers, those are not the usual standard for the cheap ones as they only go to about 20A.

Jack A Lopez

4 months ago


For me, the complicated thing about this, is that not all the turbines are guaranteed to be turning at the same speed.

Mostly I was considering just two of the options: outputs from rectifier bridges wired in parallel, or outputs from rectifier bridges wired in series.

I know these two ideas have already occurred to you, because you drew picture diagrams of specifically those two cases.

Wired in series

Wired in parallel

My first intuition was to wire in parallel, but after thinking about it a little bit, and drawing some diagrams and stuff, I think that will lead to a circumstance in which only one turbine is doing work, namely the fastest one, making the highest voltage pulses.

I mean, it would preferable to have all the turbines contributing work, at the same time, and think that is what you will get with all turbines wired in series.

Also, in series, all the voltages add together, which means you have to have an inverter whose input can handle a large DC input voltage. E.g. the worst case, when all turbines are working full speed, and pushing 48 volts each. Then those voltages add together to give, roughly, 48+48+48+48+48 = 240 volts!

Also I was thinking, for this problem, a simulation might very helpful.

Someone on this forum was asking about circuit simulators, just a few days ago,

You know, each one of those little 3-phase rectifiers, is actually 6 diodes. So 5 rectifiers is 30 diodes, and that is a lot of diodes to think about, for just drawing it on paper, but it would probably be easy for software to simulate that. Ideally the simulation would show you the case of a, "totally blocked" rectifier, i.e. all its diodes reverse biased, all the time. Also you could observe where the time-averaged power is going, preferably from the turbines to a load.

zeak1975Jack A Lopez

Reply 4 months ago

this low rpm turbine, running with flow water, and get moderate wattage about 1.9kw to 2.1kw each...