I know that it is Cosine of Angle between Voltage & Current. But I want to know its significance.
2007-01-09 22:26:20 · 8 answers · asked by E_Shrirang 1 in Science & Mathematics ➔ Engineering
The significance of power factor lies in the fact that utility companies supply customers with volt-amperes, but bill them for watts. Power factors below 1.0 require a utility to generate more than the minimum volt-amperes necessary to supply the real power (watts). This increases generation and transmission costs. Good power factor is considered to be greater than 0.85 or 85%. Utilities may charge additional costs to customers who have a power factor below some limit.
AC power flow has the three components: real power (P), measured in watts (W); apparent power (S), measured in volt-amperes (VA); and reactive power (Q), measured in reactive volt-amperes (VAr).
The fraction of power actually used by a customer's electrical equipment compared to the total apparent power supplied, usually expressed as a percentage. A power factor indicates how far a customer's electrical equipment causes the electric current delivered at the customer's site to be out of phase with the voltage.
The ratio of watts average power (the average power measured in watts) to the apparent power of an alternating-current circuit. By definition, the equation below holds, which is the ratio of instrument readings.
KW=SQRT(3)*VOLTAGE*AMPERE*COS Theta/1000
,where Cos Theta=power factor.(for three phase circuit)
A watt-meter indicates average power, and electrodynamometer or iron-vane instruments show rms voltage and current. For the steady-state ac circuit under sinusoidal voltage and current, pf = cos θ, where θ is the phase angle between the voltage and current. This definition is restricted to sine waves of the same frequency.
2007-01-10 04:06:24 · answer #1 · answered by Anonymous · 2⤊ 0⤋
Well i will try to explain in simplest terms....Power factor in electric circuits indicates the amount energy actually consumed by the connected load. Because it is simply the ratio of real power versus the apparent power. Real power expressed in Watts is that part of power consumption that is converted to heat and/or mechanicals which is in some way may be usefull depending on the purpose while apparent power is the vector sum of reactive power and the real power. Reactive power is that part that is just necessary to energize some electrical circuits like motor windings, flourescent ballast, etc....they are not actually with usefull effect with the end user but only utilized by the device itself to come out to its purpose.
2007-01-10 00:46:55 · answer #2 · answered by keen_eyes 1 · 0⤊ 0⤋
The magnitude differance between the voltage & current.
power factor depend upon what type of load used.
2007-01-09 22:43:00 · answer #3 · answered by R.T.Dharaneeswaran . 1 · 0⤊ 0⤋
Power factor is the ratio of the real and apparent power. Read more here:
2007-01-09 23:31:35 · answer #4 · answered by Land Warrior 4 · 1⤊ 0⤋
Power Factor is present in a Resistor, Inductor and Capacitor.
Please refer 'BASICS OF ELECTRICITY AND ELECTRONIC ENGINEERING' by Ravish Singh for full details.
2007-01-09 22:31:00 · answer #5 · answered by Anonymous · 0⤊ 0⤋
higher the power factor, higher the load.
higher the power factor means efficiently using the power
2007-01-09 22:30:58 · answer #6 · answered by hulchul 3 · 0⤊ 0⤋
P' = v [R1(R1+R2)^2 - 2R1R2(R1+R2)]/(R1+R2)^4 Set P' = 0 to find the value of R2 that gives maximum power. This is equivalent to setting the numerator in P' equal to zero. R1(R1+R2)^2 - 2R1R2(R1+R2) = 0 R1(R1+R2) - 2R1R2 = 0 R1+R2 - 2R2 = 0 R1 - R2 = 0 R2 = R1 So, maximum power occurs when R2 = R1.
2016-05-23 02:58:20 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Power is measured in "watts" and is equal to resistance times current.
2007-01-09 22:34:09 · answer #8 · answered by Anonymous · 0⤊ 1⤋