1

I built a wind turbine a while back and have been using it to power lights in my house. It gives out 3-phase in star setup with no neutral. Neutral is buried in epoxy resin in the casting.

It feeds into a three phase rectifier down at the house and charges batteries. Generates 500 W peak.

I recently got my hands on a good number of single phase toroidal 400 W each transformers. I want to use them to step up the voltage at the base of the pole and step back down at the far side as it is a long distance (100 meters) and might give less voltage drop with higher voltage using these.

How can I connect these? Any diagrams I see online seem to require the neutral to be available.

JYelton
  • 32,302
  • 33
  • 134
  • 249
Omasín
  • 23
  • 2
  • You could probably connect them across the phases as if your turbine was Delta. Do you know what voltage you get from the turbine and how it compares to the ratings of your transformers? – brhans Nov 22 '21 at 23:46
  • What is the voltage out of your generator? what is the voltage rating of the transformers you have? – Jack Creasey Nov 23 '21 at 00:34
  • 1
    I would be inclined to connect delta-wye - transmission line - wye-delta if the transformer voltage permits. You should not need any neutral connections. –  Nov 23 '21 at 00:59
  • The Voltage out of my generator is 0-30v. The transformers are for mains use down to 16 and 24v – Omasín Nov 23 '21 at 17:53
  • 1
    Frequency will be a potential issue. For eg 60 Hz rated transformers higher frequencies within reason will work. Lower frequencies will allow less peak voltages without saturating. Much higher frequencies will reduce allowable power levels.|| Connect primaries phase to phase in a delta and secondaries the same. Same in reverse at other end. – Russell McMahon Nov 24 '21 at 05:46
  • +1 for telling us the alternators voltage output. Other info that will help: is there a voltage regulator for the alternator? What frequency (or, how many RPM is your shaft speed)? Have you measured the actual voltage drop (do you even have a problem that needs fixing)? Any reason you can't simply increase the alternator's output voltage (increase rotor current)? – Daniel Chisholm Nov 24 '21 at 12:36
  • Tell the (lightly loaded) generator voltage when its frequency is the lowest your transformers are specified to work at. Basically, if no more that 24 V, you're fine. (If less than 16 V, use lower voltage tap, if less than 8 V, use 16 V & 24 V taps.) Now, if the voltage was higher and *a good number* means *no less than nine*, you can series connect low voltage windings of multiple transformers. – greybeard Jan 14 '23 at 13:28
  • @DanielChisholm `increase rotor current` begs explanation: increase current in generator field coil? – greybeard Jan 14 '23 at 13:48

1 Answers1

2

The transformers are to be 'star' connected using the 16 V secondaries.

enter image description here

Maximum transmission voltage would be about √3 times the transformer primary (mains) voltage.

It would be needless to connect the neutral points.

vu2nan
  • 15,929
  • 1
  • 14
  • 42