Answer / kapil soni

Electrical machines work on the principle of conversion of
electromagnetic energy.A part of input energy is consumed
for creating and maintaining the magneticfield.This part of
the input energy cannot be converted into active energy and
is returned to the electrical network on removal of the
magnetic field. This power is known as “reactive” power Q.
The Q Power flows back and forth, causing 90º Out of phase
shift between the current and voltage waveform.This
Reactive Power has one half of the Power In the positive
area and the other half in the negative area.
Unlike true power, reactive power is not useful power
because it is stored in the circuit itself.
This power is stored by
1)Inductors,
Because they expand and collapse their magnetic
fields in an attempt to keep current constant,
2) Capacitors, Because they charge and discharge in an
attempt to keep voltage constant.

Answer / pradeep

reactive power is mainly involve in the transmission line.
in transmission line, they have resistance,
inductance,capacitance.. these are all either store the
energy or dissipate the energy. so that we have a some
losses in the transmission line. this losses will reduce the
generating power and finally we get the power less than the
sending power. generally the output of the generating unit
is represent as kva. apparent power=real power + reactive powr..
real power is part of the power which is used by loads and
then reactive power is not a usefull power.by connecting the
shunt capacitor in parallel we easily inject the reactive
power to the line,becoz capacitor having a leading current
which minimize the lagging current produced by inductance.
reactive power is also called as imaginary power which is
not used for else..

Answer / kani

The role of reactive power is very important in power
generation as generation revolves around the priciple of
induction.This is the cause for magnetic field by which the
power is gererated.

Reactive power=VI SinQ
If the phase angle between voltage and current is zero then
sinq=0 ,there is no reactive power ,there is no magnetic
field ,there is no power generation

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