Can we improve power factor by generating reactive power?

Replies

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  lal

  Actually a generator supplies the necessary reactive power to the load along with its active power requirement. It is already generated according to the need. The reactive power generated is controlled by the generator excitation and the active power is controlled by prime mover input. Further, the excitation is controlled by AVR. It is a closed loop system which keeps the generated voltage a constant. If more reactive power is needed by the load, then the excitation is increased by the AVR, that is the magnetic flux in the alternator strengthens. So, it's the reactive power that actually controls the voltage output of a generator.
  
  Now if we were to generate more reactive power by a generator, we need to increase the excitation. But the problem now is that, as the excitation is increased, the voltage also starts increasing. Now a generator which is not in synch with others working in parallel cannot be connected to the bus.
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  Naga teja

  lal can you tell me the link where i can find more description about this
• 

  lal

  Not sure about the link. Try searching a bit on AVR and reactive power generation. Something useful should sprout up.
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  Naga teja

  k thanks.is there any other new methods for pf correction
• 

  lal

  Power electronics is being tested more in power factor improvement now. But still its the capacitor banks and over excited synchronous machines that are used for power factor correction in much industrial applications.
  
  Even home appliances like induction cookers are a threat for low power factor. Having induction cookers usage being widely increased, the inductive loads even in domestic sector is very much on the increase. And that too during peak hours which causes much more stress and ohmic losses heat in transmission lines.