Answer / d.h.waiker

Harmonics are generated in electrical A.c systems due to
non-linear loads. There are even harmonics multiples 2,4.6
etc and odd harmonics multiples of 3,5,7 etc. There are
current Harmonics as well as voltage Harmonics .These
Harmonics will cause un necessary heating in th electrical
equipments resulting the to fail prematurly.Bad effects of
Harmonics are mitigated by harmonic filters ( Active or
paasive filters ). Active filters generates Harmonics of
oppsite polarity to system Harmonis to nullify the effects
where paasive filters give low impednace path for for
Harmonics. ( Filter is nothing but combinatoion of
capacitor and inductor to create least rsistive path for
Harmonics )

Answer / prosenjit majumder

It is the multiple of fundamental frequency . If
fundamental frequency is 50Hz then its harmonics are
100Hz , 150Hz , 200Hz .... and so on . It generates due to
improper switching action .

Answer / ej ram

except fundamental ie primary frequency other frequency
signals ie odd frequecy signals are called harmonics. they
disturbance the Grid and equipments.

Answer / umair qayyum

Deviation of an ac signal from pure sinoside causes the
harmonics to exist.They are generated both because of non
linear loads; and generators because of the nonuniform
srator windings and magnetic fields in practical case.
When a sonosidal voltage is applied to a linear load,a
proportional current is also drawn with it.But when it is
applied to a non linear load,it causes the current to vary
disproportionately with the voltage due to which
nonsinosidal waveforms are created containg
distortions,whereby 50/60 hertz frequency contains numerous
waveforms superimposed upon it which are the multiple
frequencies of the normal 50/60 hz sine wave.

Answer / felixraj

it is the integral multiples of fundamental frequency.
it is due to non-linear load.
by using filters .

Answer / hazem el-henawy

Harmonics are integral multiples of some fundamental
frequency ,if the fundamental frequency is f, the harmonics
have frequencies 2f, 3f, 4f, . . . etc., when added
together, result in a distorted waveform, It generates due
to improper switching action, they disturbance the Grid and
equipments.

filters generates Harmonics of opposite polarity to system
Harmonics to nullify the effects,We use filters to get a
stable system.

Answer / gopal

un wanted damping frequencies , by switching action by using
filterers

Answer / p.aruna devi

Unwanted signal is known as harmonics .it generate due to
double the frequency.

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