sowjanya

• Aug 10th, 2011

 

because in transmission lines having reactive elements

parthiban

• Sep 4th, 2011

 

Inductive load is reactive sink which has to be provided. While using more inductive load, real power reduces and reactive power is increased because apparent power has to be maintained constant.

Harish P. Girhe

 Profile Answers by Harish P. Girhe Questions by Harish P. Girhe

• Sep 10th, 2011

 

Power triangle is form by three types of power viz active, reactive and apparent power.
For transferring the power reactive acts as an envolope. Without this power can not be send. It means all three power are dependent to each other.
Read more about power triangle.

Harish P. Girhe

 Profile Answers by Harish P. Girhe Questions by Harish P. Girhe

• Sep 10th, 2011

 

It is also useful to maintain the secondary terminal voltage when it becomes more than sending end voltage, ie reducing capacitive power factor. (this posibility is neglegible)

Sagar_upadhyay

• Sep 24th, 2011

 

In most of the power stations, the generation takes place by synchronous generators. The synchronous generators are doubly excited in nature. When the rotor is fed with a DC field, power is generated. The purpose of this power is to just create a magnetic field & not to do any physical work, that's why it's called reactive power. In short, all the field windings generate reactive power which get transmitted into the transmission system.

bittu123

 Profile Answers by bittu123 Questions by bittu123

• Nov 10th, 2011

 

If alternator is Overexcited, it will deliver reactive power with lagging current
while in Underexcited, it absorb reactive power with leading curreent

But, it always(under or over-excited) deliver real power.

WHY it needs or absorb reactive power??????????
Actually synchronous machine maintains constant flux. when dc field current gets reduced(undrexcited), To strengthen main field, it absorb reactive power(draw current from ac supply mains).
In reverse, when dc field current gets increased(overexcited), To weaken main field, it deliver reactive power to the bus bar.
All these are controlled by magnetising and demagnetising effect of armature reaction