Power Systems - Harmonics

Discussion in 'Power Electronics' started by antonion, Sep 17, 2016.

  1. antonion

    Thread Starter New Member

    Nov 16, 2015
    Hy guys I want to ask sth
    Why even harmonics(2nd,4rth,..) in power systems cancel themself and we cosider them zero,while the odd harmonics are important?
    I suppose because if we take into account a sine wave and its the operating frequency is 50 Hz, the wave of the second order harmonic in f=100Hz
    would totally fit in a half-period of the wave of 50Hz so its mean value would be zero..Is it the explanation?
  2. AlbertHall

    AAC Fanatic!

    Jun 4, 2014
    I am curious so I googled. I found a site which says the same as the TS but didn't explain. Then I found this site:
    which says:

    "It is well known that even order harmonics produce
    higher detrimental effects in power system loads than odd
    order harmonics. For this reason international power
    quality standards define very strict limits for even order
    harmonic components."
  3. antonion

    Thread Starter New Member

    Nov 16, 2015
    However it also says that "the main effect that produces even harmonics is the asymmetry of voltage or current waveforms"
    and in the introduction"This paper reports the results of the monitoring of second order voltage harmonic group and subgroup, as defined in IEC harmonic measurement standards, in a low-voltage distribution systems and the effect on the asymmetry in voltage waveforms"
    but I meant in a symmetric circuit.