What is the significance of power factor in switching power supplies?

[neduet]

Hello friends

what is this term meaning (power factor correction)

and from my book some lines are

The simplest form for power factor is the ratio of the equivalent series resistance to the impedance of the device

what its meaning?

and

PF= power loss/input power resulting ratio is the "power factor" WHAT is this?
can we say above line is same as this PF = TRUE POWER/APPARENT POWER
explain please

thanks

 

[russ_watters]

No, PF is apparent/true.

 

[negitron]

No, PF is apparent/true.

What? No, that's wrong:

http://en.wikipedia.org/wiki/Power_factor#Definition_and_calculation

 

[stewartcs]

Hello friends

what is this term meaning (power factor correction)

and from my book some lines are



what its meaning?

and

PF= power loss/input power resulting ratio is the "power factor" WHAT is this?
can we say above line is same as this PF = TRUE POWER/APPARENT POWER
explain please

thanks

Power factor correction is when adjustments are made to the electrical system to improve the power factor (i.e. bring it closer to unity). This can be accomplished through various components such as synchronous generators, etc.

PF = P/S = true power / apparent power = cos(theta)

CS

 

[berkeman]

PFC also has context in switching power supplies. Look at the Switchmode Power Supply section of this wiki entry:

http://en.wikipedia.org/wiki/Power_factor

You can design your SMPS to better approximate a simple resistive load, instead of the diode-capacitor bridge imput characteristic (which has a louse PF).