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Inductive Rectifier with internal DC load

  1. Mar 22, 2015 #1

    I'm new here so I'm not sure how things work but I'd like some help on a question.

    How do I go about finding an expression for both i_in(wt) and the average current?
    This is the inductive rectifier circuit I'm working with.

    I've tried using the inductive voltage equation V_L = L* (di/dt) and then integrating to get some kind of expression but haven't been able to come up with anything yet.

    Any help would be greatly appreciated. Thanks.

  2. jcsd
  3. Mar 22, 2015 #2


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    Gold Member

    This question seems to relate to a choke input ripple filter. The battery causes the rectifier to base line clip the half sine waves coming from the rectifier. We deduct the battery voltage from the generator voltage. The resulting narrow pulses, if viewed in the frequency domain, consist of a DC component, a fundamental at power line frequency and all the harmonics. It is usual for engineering purposes to ignore the harmonics. We can take the height of the remaining pulse as our peak-to-peak ripple at fundamental frequency. Then the peak ripple voltage, Vp, is half the peak-to-peak. The peak ripple current, Ip, is then found from Vp and the inductive reactance, using Ohms Law. The ripple current at any instant is Ip sin wt. The average current is 0.577 times the peak.
    One problem with the question is that the rectifier produces a DC voltage component, and the resistance in the circuit is zero. From Ohm's Law, this leads to infinite direct current flowing.
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