Answer / mihir gajjar

*Simply Harmonics is Integral multiple of fundamental
frequency.* By means of different euipment different order
harmonics are generated 3rd harmonics generated by AC
Generator itself,5th harmonic generated by transformer&
different order harmonics are generated by electronic
circuit like rectifier,inverter o/p.
*Harmonics spoils many component in power system.
problems like mal function of MCBs,Excessive Heating in
neutral conductor,excessive eddy current loss in conductor
due to skin & proximity effect,it creates the problem in
Motor & Tranformer iron loss.

Answer / saikishore.katuri

Harmonics is Integral multiple of fundamental
frequency.That means if the fundamental frequency is f, the
harmonics have frequencies f, 2f, 3f, 4f and the property
is that they are all periodic at the fundamental
frequency.The sum of harmonics also periodic at that
frequency.
If we see the generation of harmonics different order
harmonics are generated 3rd harmonics generated by AC
Generator itself,5th harmonic generated by transformer&
different order harmonics are generated by electronic
circuit like rectifier,inverter etc..
It creates many problems like in power systems are

Harmonics can cause all sort of problems Excessive Heating
in
neutral conductor,excessive eddy current loss in conductor
due to skin & proximity effect,it creates the problem in
Motor & Tranformer iron loss.It will give problem on
waveform distortion. To avoid this designing of the neutral
cable size very important.

Answer / graeme

Harmonics are frequency components that are whole number
multiples of a fundamental frequency. For example, in a
60Hz AC supply system, 2nd harmonic is 120Hz, 3rd harmonic
is 180Hz and 4th is 240Hz.

Harmonics are most often caused by non-linear loads (eg
transformers where the line current is distorted by the non-
linear B-H characteristics in the core), rectifier circuits
and phase control circuits. In all these cases, the
resulting load current waveform is not a pure sine wave, so
harmonics are present.

Harmonics can cause all sort of problems such a voltage
waveform distortion and the different harmonic frequency
components causing different impedance values to appear in
reactive components.

Answer / shahul

Harmonics Generally created in Non-Linear Circuits,for
eg.VFD,Inverters..etc.
It will create problem on waveform distortion.So designing
any power system with non-linear circuits harmonics to be
considered so that designing of the neutral cable size very
important.

Answer / kirthika

In fourier transform the complex waveform can be shown to
be built of a series of sinusiodal waves whose frequencies
are integral multiples of frequency of fundamental wave is
harmonic functions are called harmonics

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