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Cockcroft-walton generator, How to increase voltage?

  1. Dec 18, 2012 #1
    Hey guys,

    I have a question concerning CW generator which might be a bit stupid:

    How can we increase the voltage by using an AC source, capacitors and diodes ?

    Capacitors is used to store charge, diode to block current flowing the "wrong way", since its an AC current, capacitors will charge and discharge continually.

    By using diodes we could transform ac into dc, but how can we increase it?
  2. jcsd
  3. Dec 18, 2012 #2
    A capacitor charges to the peak value of an AC waveform half cycle, say the positive half cycle.

    This is obviously higher than the RMS or effective DC value of that same waveform.

    By using a suitable arrangement of diodes and capacitors we can arrange for the negative half cycle to appear reversed and therefore add to the positive peak.

    This results in a voltage doubler circuit, the cockcroft being one variation of this.

    The process can be carried further to achieve greater multiplication quadruplers and higher multipliers are available.

    Of course you don't get something for nothing so as the voltage output is increased so the current availble decreases.
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