Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Connect two alternators together to double the output voltage

  1. Dec 9, 2008 #1
    Is it possible to connect two alternators together to double the output voltage, is there a way to do this?
    Eg: Say two 12v Alternators connected to get 24v etc.

  2. jcsd
  3. Dec 10, 2008 #2
    Re: Alternators

    If you mean alternators without rectifiers (as in cars) it might be tricky because they have to be locked in phase which is usually done with them in parallel.
  4. Dec 18, 2008 #3
    Re: Alternators

    Yes, it could be done, but it's no easy task and would be impractical.

    The alternators would require identical internal construction, they would have to be properly phased (and remain locked to that phase) therefore they couldn’t be belt driven as slippage and belt travel would alter their phase, so they would require chain or gear drive and must spin per identical ratios, AND they would require a 24 volt DC source such as a 24 volt DC battery to produce their exciter coil current so they could begin to output voltage. Additionally, they couldn’t have self-contained regulators nor the rectifying diodes, as they would need to be constructed externally for this 24 volt construction.

    Considering all the above factors, it would be far less complicated and far less expensive to simply purchase an alternator that was designed to output 24 volts. Hope this helped.
  5. Sep 1, 2010 #4
    Re: Alternators

    I have a information seeking post in 'Electrical Engineering' relating also to alternators joined in series to produce a larger output. The plan is to build a mechanism that has several alternators connected in series to produce a combined 240v AC power supply to run a house, using a driver that requires only a small energy consumption. Something like what wind turbines are capable of but without the restrictions that plague them and hopefully a lot cheaper too. But here you mention that the alternators would need to be of identical internal construction, have no independent regulators or rectifiers, and be turning at precisely the same speed. Question: if they are the same brand and same size would that mean they are constructed identical internally; I mean is it critical that they are totally 'identical' in every aspect? Also, if what powers them (no belts or chains involved) provides a consistent force would that mean that they are all turning at precisely the same speed (as required)? If they are not, what would happen?
  6. Sep 2, 2010 #5
    Re: Alternators

    There seems to be a bit of a terminology problem here do you mean alternators (produce AC) or generators (make DC). If you are starting with an alternator all you need to boost from 24 to 240 is a transformer.
  7. Sep 2, 2010 #6
    Re: Alternators

    Thanks for your response: Yes I am talking about Alternators.. The plan, as is described in the lead post, is to construct a mechanism that is capable of proving all of the energy needs for my home. Wind turbines are far too expensive for me to purchase so I decided to try to make something that will do the same job but without relying on the forces of nature to drive it. Now, you mention that all I need is a 'transformer'. So, does that mean that I can convert a small voltage to a larger voltage that will be sufficient to provide for all that is needed in the home at any given time? I have no idea what wattage or amperage will be needed and that's what I am trying to find out. Secondly, once the mechanism is producing sufficient energy it will need to be regulated to suit the usage at any given time (is that right?). I mean: if all of the airconditioners (for example) are off the energy requirement will be less than when they are all turned on, so the mechanism will need to be regulated to provide the varying levels of energy on demand (right/wrong?) . If more than one alternator is used and connected in series, you mention the need to be very careful that the internal construction is identical and that they are being driven as the same speed at all times. Would it be the same if I used generators (DC) and then used a converter to end up with the AC that is needed? . Your further enlightenment will be much appreciated. Understand that, although I have a basic understanding of what I am planning to do I do not have much knowledge of electrical engineering.
  8. Sep 2, 2010 #7
    Re: Alternators

    Next question, what do you intend to use to drive the alternators?
  9. Sep 2, 2010 #8
    Re: Alternators

    Thanks again. Not sure yet but something that is capable of blowing air at a steady rate constantly without using a lot of energy to do it.
  10. Sep 2, 2010 #9
    Re: Alternators

    Sorry Jo,
    I thought you were on the 'Electircal Engineering' forum (getting mixed up a bit). If you would like to take a look at my posts there you will get a full explanation of what I am planning and what problems I am facing. Thanks for that.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook