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Power Sources in Series/Parallel ?

  1. Mar 21, 2005 #21
    you see at this point i'm unable to answer the first paragraph, because this is in theory. i'm trying to find out just how much power i can squeeze out of a generator if i need to. (btw..wut the heck is a wall wart?) and it will be for only one load.

    i need this generator to be really small (like teh size of an alternator, small). and all of them would be turning in a synchronized fashion, with rare and small fluxuations (hopefully)
  2. Mar 21, 2005 #22


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    Hey Cliff. Just thought I'd throw this out even though it is slightly off topic. It is not at all difficult to put AC generators in parallel. They tend to self regulate their speed. Just make sure that each generator is in good working order before hooking them in parallel. Both generators need to have their governors in top notch condition. There speed is set as close together as possible. Then the phase is checked or adjusted so that they are in phase. Many times this is just accomplished by having a very slight speed error and waiting for the generators the come in phase. The switch is then thrown to hook them together.
  3. Mar 21, 2005 #23


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    Oh, I had guessed it to be not too difficult to couple 2 generators if designed to work as a system, but this is seemingly about ad-hoc solutions more than integrated designs. Now how the power grid can stay synch'd across such huge distances and different loads as a matter of planning (guessing) and reacting....well now we're more off topic. :smile:

    infamous - a wall wart is the transformer that plugs into the wall, typically a 2" by 2" by 2" black box with a tiny cord that leads to like a cell phone charger or what not - its ugly hanging on the outlet hence the wall wart

    A good sized automotive alternator can produce 12V and around 100A (1200W) or maybe find a heavy-duty one from a diesel truck to make up to 200A so that's 2400W.

    You need a lot of power to turn that alternator (or generator) so I don't know what you're source is but it would need at least two spare HP (746W=1HP) to get that kind of output.

    Not sure of your application, but it sounds like it needs more details presented (hint hint) to make any kind of guess as to the feasibility.
  4. Mar 22, 2005 #24
    yes, unfortunately i can't mention more really. check my post about "patents" in the general talk forum...see this is something that i could patent, hopefully, and gain royalties from. so before going through the fees id rather find if its even possible, so im gathering scattered info and putting it together peice by peice. and as for the alternators, you can also get car ones at about 200A (for big sound systems), and there would be about 24 of them (yeah thats right..) possibly more, not exactly alternators however...but something along those lines, producing AC electricity so that it can be manipulated, and used for the load.
  5. Mar 22, 2005 #25


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    Infamous - you have many challenges to bring something like this to a working prototype. It should work just as well at a small scale as a large scale other than efficiency. And the use of 24 generators doesn't seem efficient or cost effective, look at a 777 airplane that uses 2 big jets for a big increase in fuel economy over the 4 smaller jets on a 747. And a 60W scale model should be easy to build and test the feasibilty of the concept even if it doesn't account for potential scalability problems.

    You can actually get 350A alternators in the regular alternator sized case for large sound systems and bigger cases for higher capacities. But for yours, a larger single unit still seems better. Anyways, I'll use your numbers. 24 units at 200A and 14.4V (pseudo-standard cold alternator charging temp) is 69kW of power or 92.7HP. The alternators need roughly 2000RPM spin too, about 243 ft-lb of torque with a 1:1 pulley ratio.

    Yes, the alternators are wound for low voltage and high current and rectify the 3-phase AC voltage to DC. They could be wired differently to make a single phase higher AC voltage with lower current. But why not just one 69kW generator and avoid the losses (and expense) of any conversion?

    Well the patent thing is pretty well been covered, you should already have an idea that the prospects of pursuing a patent and making a profit from selling it are pretty much a few decades out of touch with the times. One company I work with has found a company in a friendly european country that is stealing one of their patented formulas for a product. After investigating the cost at 100+ thousands of dollars in legal fees and travel expenses and factoring in the yearly sales and gross profits from those sales it was determined that it would take many years to recover the money spent protecting the patent (assuming they win the court battle). Just how many days can a person justify traveling to court with lawyers in a different country? (the other company has plenty of money and lawyers to tie it up in court) Look at how poorly copyright laws are enforced overseas, you can get $10,000 pieces of software for $10. The new mantra for inventors is to bring a product to market fast enough to get enough market share to establish a brand name before the copycats arrive.

    Real big question is, what is so different about your idea from what is already out there? Unless you have some new never before used method of spinning the generators, this is not really a patentable idea or one unique enough to prove to a court that someone else has infringed on your idea. I'd guess you might even find Edison's patents referenced at the very first patent search, there was a lot of competition and discovery with Westinghouse/Tesla that resulted in many patents being issued. You may find a way to get a patent to improve on an existing design, but someone could just as easily improve yours and pay you nothing while you're stuck with 10 or 15 grand in legal fees to get the patent. Or throw lawyers at you and wait until you run out of money from paying lawyers to fight them in court with counter-suits. Microsoft was quite good at this in the 80s/90s and it was a big deal when a small company like the one that made doublespace actually won a settlement against them.

    Not trying to be a buzzkill, but trying to establish some of the reality of production and legal protections (and costs of those protections) that go with it. There was a show on the TechTV called "Invent This!" and it was truly sad to see so many people invest their life savings into ideas they were sure were going to work. There were only a few success stories and in those the people did it all: invent, design, produce, market, and distribute their product.
    Last edited: Mar 22, 2005
  6. Mar 23, 2005 #26
    hmm..thanks for the info on the patents, however my idea isn't just the generators, that is only a part of it.

    as for the 69kw generator..how big would one of those be? lol because size is definitely a factor.
  7. Mar 23, 2005 #27


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    It would take up less volume than 24 little guys with the same total power. :smile:
  8. Mar 23, 2005 #28
    so the size would be...lol
  9. Nov 1, 2009 #29
    Re: Power Sources in Series/Parallel....?

    So Infamous_Q, just out of curiosity wanted to ask, did you file for patent for what you wanted to do? Or do you still need any help in filing patent?
  10. May 24, 2011 #30
    Re: Power Sources in Series/Parallel....?

    I need to add two, or more (say 20) dc power sources, in a series-parallel combination
    to get both Voltage add-up (in Series) and current add-up (in parallel).
    Please advise that:
    1. can the above be done without facing complications.
    2. for adding two or more dc power sources (for battery, and for electronic), the
    voltage of each dc power source must be equal (say all are delivering 5v, or 3v, or
    3. should the current output also be equal of all dc power sources to be added in
    Series/Parallel/Series-Parallel, if the above (2) is true (say all should be delivering 4
    mAmp, or 5 Amp, or whatever?
    4. Please give detailed answer, with diagram, if any.

    I need a quick reply, for which I shall be grateful. Please
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