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Pulsing high current into capacitive load?

  1. Jul 13, 2008 #1
    I have to pulse 80 Amps @ 1 KHz into a capacitive load of a few uF. Unfortunately the RC constant is high enough that it prevents the next pulse to start from 0 amps. So in a sense the pulse generator delivers about 70 to 80 amps per cycle instead of 0 to 80 amps like it would in a non-capacitive load.

    I fixed this temporarily by hooking up a 0.75 ohm high current resistor in parallel so it could discharge the load when the pulse is off. However I'm wasting a lot of power this way.

    So I'm wondering if there is another solution?
    Last edited: Jul 13, 2008
  2. jcsd
  3. Jul 14, 2008 #2


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    You might try being more specific about the purpose of your setup and what it is intended to accomplish.
  4. Jul 15, 2008 #3
    put a higher resistor instead of a such small one.

    your decay rate should be faster than 1msec, lets say it is about 0.2msec, so RC = 0.2msec => R = 200ohms?
  5. Sep 30, 2008 #4
    Have you tried using a variable square wave generator and a mosfet?
  6. Sep 30, 2008 #5
    Thanks for replying, but the problem has been solved two months ago. We basically generated a second low powered 180 degree out of phase pulse to discharge the cap.
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