Answer / syed qamar abbas

Power factor is the cosine of angle between voltage and
current.If the voltage is leading and current is lagging
that means power is of lagging nature, if current is
leading voltage then its of leading nature and if both
voltage and current are in same pahse then its unity.By
injecting reactive power power can be corrected, if power
factor is lagging then it can be corrected by injecting
capacitive power (KVAR)by means of capacitor banks and if
its leading then by means of inductors.

Answer / gul mohammed ibrahim

power factor is defined as the ratio of real power to the apparent power.
real power is the power which is converted in to active energy
Reactive power is the power which is Derive by motor (inductive load) to generate and maintain flux
apparent power is the vector sum of real power &Apparent power
To Improve Power factor We can Connect A capacitor parellel to the load

Answer / madhu sudhan

p.f is defined as the cosine of the angle between voltage
and current in an ac ckt.
it may also be defined as the ratio between the active
power and apparent power.
It also can be defined as the ratio of resistance to the
total impedence inthe ckt.
it is very impartant to correct the p.f as it plays an
impartant role power systems.There are differnt methods
available for p.f correction.THE P.F VARIATION OCCUR MAINLY
DEPENDING UPON THE TYPE OF LOAD,BECAUSE THE REACTIVE POWER
VARIES WITH THE TYPE OF LOAD.
For inductive loads the reactive power consumption is more
and the p.f decreases with the increase in load,hence
inorder to improve p.f a capacitor should be shunted as it
generates the required reactive power,we also have
different equipment like synchronous condensers etc.

Answer / naresh

The accurate defination is it is the angle between
Fundamental voltage & Fundamental current. we can calculate
the fundamental components from fourier transform.

in case of linear load(resistor,capacitor,inductor)
we can improve it
1.by connecting capacitor loads
2.using Synchronopus condensor(overexcited synchronous motor
under noload condition)
3.by using Power Factor Correction Unit
in case of non linear load(containing
converters,inverters,rectyifiers)

1.by adjusting the delay angle,extinction angle

Answer / pernati raja

power factor is cosine of the the angle between voltage and current or the ratio of real power to reactive power. for an ideal operation power factor is unity. but in practical operation it is less than unity. if current leads the voltage power factor becomes leading and if current lags power factor becomes lagging in nature.

## lagging power factor can be improved by injecting the capacitive reactive vars in to the system. and different methods are
1.by connecting shunt capacitor
2.by connecting series capacitor
3.synchronus condenser

##leading power factor can be improved by injecting the inductive reactive vars in to the system. different methods are
1.shunt inductor
2.synchronus condencer

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