i'm a 3year student taking electrical course. i have a problem with the power factor term.lets say when someone say, the generator generate 80kw at 0.8lagging power factor? what is it actually mean? what is the real power value? and what is the reactive power value? pls help...
2007-08-31 18:27:39 · 6 answers · asked by luckyguy 2 in Science & Mathematics ➔ Engineering
The power factor is the cosine of the angle displacement between the voltage and current. It is generally shown as a right triangle where the base is labeled kW (real power), the opposite side is labeled kVAr (reactive power), and the hypotenuse is labeled kVA (apparent power).
If PF = 0.80, then the arccos(0.80) = 37°.
The right triangle has an angle of 37°.
The sine wave of the current lags the sine wave of the voltage by 37 electrical degrees.
A picture is worth 1000 words. Check out the diagram at the link below.
2007-09-01 01:53:39 · answer #1 · answered by Thomas C 6 · 2⤊ 1⤋
Lagging Power Factor
2016-11-02 10:49:23 · answer #2 · answered by ? 4 · 0⤊ 0⤋
What we have here is 100 kVA, and you can draw a triangle with hypotenuse 100 [= 80/0.8] and one side 80, and the other side (60 in this case) will be the reactive power. This is the sort of thing that you get when the load has lots of inductive elements, such as fluorescent lamps and electric motors. Power companies don't like this because they have to deliver the total power but can bill only for the resistive component. So, if you are a big customer with a bad power factor, they may lay on a surcharge.
2007-08-31 18:34:51 · answer #3 · answered by Anonymous · 2⤊ 0⤋
Lagging power factor means that the current phasor lags the voltage phasor (inductive load)
Opposite is the leading power factor, when the current phasor is ahead of the voltage (capacitive load).
Power factor is a cosine of the angle between the voltage and current.
Active Power P = S x cos(θ)
Reactive Power Q = S x sin(θ)
Apparent Power S = U x I
Even though units are the same (Watts) it is a custom to use
W when describing active power
VA when dealing with apparent power
VAr (VA reactive) when describing Q.
In your problem P and cosθ are given.
2007-08-31 21:30:26 · answer #4 · answered by nosf37 4 · 2⤊ 0⤋
This means that it can 0perate a I0ad with Iagging p0wer fact0r "0,8" upt0 80kw,
2015-11-08 02:51:52 · answer #5 · answered by MZ Khan 1 · 0⤊ 0⤋
when my under gruond tank is empty then my pump is not start
if my under gruond tank is full and uper tank is empty then my pump is start
2007-08-31 20:06:44 · answer #6 · answered by Anonymous · 1⤊ 1⤋