Answer Posted / suresh
The power factor of an AC electric power system is defined
as the ratio of the real power flowing to the load to the
apparent power [1] [2], and is a number between 0 and 1
(frequently expressed as a percentage, e.g. 0.5 pf = 50%
pf). Real power is the capacity of the circuit for
performing work in a particular time. Apparent power is the
product of the current and voltage of the circuit. Due to
energy stored in the load and returned to the source, or due
to a non-linear load that distorts the wave shape of the
current drawn from the source, the apparent power can be
greater than the real power.
In an electric power system, a load with low power factor
draws more current than a load with a high power factor, for
the same amount of useful power transferred. The higher
currents increase the energy lost in the distribution
system, and require larger wires and other equipment.
Because of the costs of larger equipment and wasted energy,
electrical utilities will usually charge a higher cost to
industrial or commercial customers where there is a low
power factor.
Linear loads with low power factor (such as induction
motors) can be corrected with a passive network of
capacitors or inductors. Non-linear loads, such as
rectifiers, distort the current drawn from the system. In
such cases, active power factor correction is used to
counteract the distortion and raise power factor. The
devices for correction of power factor may be at a central
substation, or spread out over a distribution system, or
built into power-consuming equipment.
| Is This Answer Correct ? | 29 Yes | 3 No |
Post New Answer View All Answers
solor panels arrange some angle,panel is flat fitted energy was produced or not why?
How do the synchronizing lamps indicate the correctness of phase sequence between existing and incoming alternators?
1.how many types of relays? 2.difference between ATS& STS?
how to extend relay operating timing in 24V dc relay card (without using Timer )
How many devices can be connected in one zone of FACP
can anybody tell me that for p.f. Improvment we use capacitor banks but how to decide its capacitance. As we all know how to calculate kvar but what abt capacitance value
there is an alternator 480 k.w, 400v,50hz, 4-wire running on load having leakage alternator body earthed current 38 A. is it within acceptable limit? if yes then give reference if no then how to bring within specified limit
i have interview in Pepsi company what type of question will ask please send the question and answeer
Define closed loop control system.
What is the technical difference between On delay timer and a Star delta timer?
how the inner and outer body is separated in aircrafts?
bsec exam syllabus (mis)
Define open loop control system.
I am having a 42KW 3 phase electrical heating furnace, heating element is 80/20 nichrome material, my connections is made in such a way that 2 star connection compromising 2 coils per phase so totally 12 coils, shall if i use it unbalanced star condition (instead of 2 group of 3 phase or 1 group of 3 phase, connecting 4 phases of 5 phases) what will be the consequences and is it acceptable?
What is boucholz relay and the significance of it in to the trformer?