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  1. #1
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    Flyback PFC passes mains harmonics

    Hello,

    The attached waveform is of a flyback pfc. The mains input current is slightly out of phase with the mains input voltage, however, it still passes all mains harmonics.
    Is this expected? Similar ones fail on the third harmonic.

    •   Alt13th June 2018, 20:06

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  2. #2
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    Re: Flyback PFC passes mains harmonics

    Aren't you supposed to test it at 60W ? Why are you testing it at less than 35W?



    •   Alt13th June 2018, 20:41

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    Re: Flyback PFC passes mains harmonics

    Thanks yes, you read my mind , it is actually a 60w flyback maximum...but we need to pass mains harmonics at all levels down to 25w, including the 35w version shown in the top post.



    •   Alt13th June 2018, 21:02

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  4. #4
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    Re: Flyback PFC passes mains harmonics

    What do you mean with "passes all mains harmonics"? There's no indication for harmonic behaviour in the posted waveform.


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  5. #5
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    Re: Flyback PFC passes mains harmonics

    The results are surprisingly good, it would be a bonus if the flyback could keep switching thru the mains zero Xing - but sometimes you can't have everything - well done ...!



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