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Best Way to Combine High V Low I and Low V High I

  1. Dec 7, 2011 #1
    Hi All -

    We've got two generator systems that need to be combined for a hybrid-summed output.
    One is a standard alternator gen-set with low-medium V and high I... the other is a high V low I system...
    The outputs can be rectified or otherwise altered. But the goal is to increase the overall output of the alternator system by said combination.
    Combination of the two is the goal...

    We've had trouble with op-amp solutions. Anyone with a suggestion or experience would be appreciated. And we're hiring ;)

    Thanks all and Godspeed ;)
    Last edited by a moderator: Dec 7, 2011
  2. jcsd
  3. Dec 7, 2011 #2
    How is op-amp come into the picture? You have two generator assume to be AC. Then you said it can be rectified. So it become DC and add together. The output is the addition of two DC voltages. So what is the op-amp for.

    I have no idea what you are trying to ask.
    Last edited by a moderator: Dec 7, 2011
  4. Dec 7, 2011 #3
    Hey Yungman -

    Thanks for the reply... Sorry for being vague. I'm asking what's the best method of adding two generator outputs, let's say two DC gen outputs, very different voltage and current aspects.
    Your input on this is valuable... simply... take two DC electric outputs... one has high voltage and low current... one is high voltage and low current.. what's the best method of combining the two for an overall summed high V high I output?

    Thanks again...
  5. Dec 7, 2011 #4
    Toss the op-amps and AC... DC just makes it easier..
  6. Dec 7, 2011 #5
    I don't think you can get high V and high I from one that is high V and low I with one that is low V and high I!!!

    That is my big confusion. You only can sum the two voltage, but the current capability is equal to the low current one. The low current is the gating one.

    Am I missing something?

    Eg. If you put a 1000V 1mA supply in series with a 5V 1A supply. You get 1005V, but you can only draw 1mA. You draw over that, you either burn the 1000V supply or the voltage will collapse.

    Op-amp is not going to help in any sense.
    Last edited: Dec 7, 2011
  7. Dec 7, 2011 #6
    Have you considered building an inverter to step up the lower voltage to the same voltage as the higher voltage supply? You may want to consider isolating the supplies with forward biased diodes but they may not be necessary.
  8. Dec 7, 2011 #7
    Use Transformers Immediately after each Alternator. The Primary Voltage Rating of the Transformers should equal the Alternator Generation Voltage. Their Capacity (KVA) should match the Alternator Capacity.
    Secondary Voltage rating of both transformer should be equal, so that they can be connected together.
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