PWM

Discussion in 'Homework Help' started by Cerkit, May 12, 2010.

  1. Cerkit

    Thread Starter Active Member

    Jan 4, 2009
    275
    3
    Hi. Can someone explain why the regular sampling method as opposed to naturally sampling reduces the subharmonic content for a given sampling frequency?
     
  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    5,448
    782
    There may not be a concise explanation. The Fourier analysis of the two methods - natural & uniform - is a difficult task. The two techniques originate from different approaches to PWM generation. The former from an analogue approach - the latter from a digital method. I guess you know that already.

    It probably transpired that harmonic measurements of practical implementations of the two methods revealed important differences [strengths / weaknesses?] which were then analysed from a detailed theoretical approach.

    Doing some reading on the topic a clue may be that there is an inherent switching timing uncertainty in the digital sample & hold approach of uniform digital PWM generation. Refer for instance, to Geoffrey Walker's (BE) honours thesis on modulation & control of converters - The University of Queensland.
     
Loading...