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kiransabarish • Oct 3, 2012

# What is a reactive power? How will it get produced or absorbed?

When i ask this question to many they tell me the mathematical equation only. i need the exact explanation for it. How will it get produced or absorbed? which elements produce it or absorb it and how? Also want to know the significance of Reactive power in power systems. Thank you!!!
grsalvi • Oct 3, 2012
Well even i was unfortunate like you to just live life by knowing them by equations (because even professors wouldn't know what exactly reactive power is ).
But in final year it was important to understand them as it is very common during project vivas.
So here i go :
PART A:
1]Every electrical load has many elements ,which are broadly classified for studies as resistors,inductors and capacitors.

2]You know that inductors and capacitors are energy storing devices.
3]So during a cycle of AC supply for some duration L & C (inductors and capacitors) store energy but then they supply some power back to source.
This power which flows back to source due to L&C is called is reactive power.

4]Hence reactive power is associated with energy transferred back from load to source.
5]The net power which is associated with energy transferred from source to load is called as real power.

5]Where as the actual consumption of energy at load is represented by term apparent power.

Now significance
a. Reactive power is responsible for maintaining voltage profile between sending and receiving end with in safe limits (Read about Ferrenti Effect).

b. Reactive power is important in motors to generate magnetic flux.

Reactive power if not maintained properly in power system it can lead complete breakdown of power grid.
Hope that explains 😀
kiransabarish • Oct 4, 2012
Well even i was unfortunate like you to just live life by knowing them by equations (because even professors wouldn't know what exactly reactive power is ).
But in final year it was important to understand them as it is very common during project vivas.
So here i go :
PART A:
1]Every electrical load has many elements ,which are broadly classified for studies as resistors,inductors and capacitors.

2]You know that inductors and capacitors are energy storing devices.
3]So during a cycle of AC supply for some duration L & C (inductors and capacitors) store energy but then they supply some power back to source.
This power which flows back to source due to L&C is called is reactive power.

4]Hence reactive power is associated with energy transferred back from load to source.
5]The net power which is associated with energy transferred from source to load is called as real power.

5]Where as the actual consumption of energy at load is represented by term apparent power.

Now significance
a. Reactive power is responsible for maintaining voltage profile between sending and receiving end with in safe limits (Read about Ferrenti Effect).

b. Reactive power is important in motors to generate magnetic flux.

Reactive power if not maintained properly in power system it can lead complete breakdown of power grid.
Hope that explains 😀
I think i got it!! but, can you explain the physical meaning of reactive power alongside the mathematical equations. I will be more clear by then. 😀
Jeffrey Arulraj • Oct 4, 2012
VI is the actual power produced in the source

VIcos(pi) is the actual power delivered at load
It depends on the component used as a load Inductor or capacitor and leading lagging all come here

VIsin(pi) is the reactance of these devices and the power the generate in the reverse direction towards the source
grsalvi • Oct 4, 2012
kiransabarish • Oct 9, 2012
jeffrey samuel
VI is the actual power produced in the source

VIcos(pi) is the actual power delivered at load
It depends on the component used as a load Inductor or capacitor and leading lagging all come here

VIsin(pi) is the reactance of these devices and the power the generate in the reverse direction towards the source
Thank you!!!
kiransabarish • Oct 9, 2012
grsalvi