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Low pass filter design

  1. Feb 26, 2012 #1

    I am designing LC low pass filter for single phase sinusoidal pwm inverter, where the cut off frequency is f = 50 Hz.

    And i have to chosse L, C such that: f = 1/2π√(LC)
    but there is many combinations of L and c that result in this cut off frequency.

    So my question is, how to choose these values?
  2. jcsd
  3. Feb 28, 2012 #2


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    Staff: Mentor

    A load is going to appear across C? This may have a major effect on the filtering ability of your L-C arrangement. You need to design it as an LCR circuit from the start, assuming you can represent your load as R.

    Apply some maths, and sketch frequency response graphs, you'll see how it behaves.
  4. Feb 28, 2012 #3
    Do you need to select real parts, or is it just values that you need to select?
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