Formula to find difference between kva and kw?

Question

and what is kvar

Answer 1

kva is kilo volt ampere i.e product of voltage and current

kw is kilo watt i.e power (p) p= v*i

both of them are units of power but kw is called as total power where as kva is active power = v*i*cos(fy)

kvar is termed as reactive power = i.e power because of reactive components in any circuit (capacitors or inductors)

total power (kw)=active power (kva) + reactive power (kvar)

the term cos (fy) i.e power factor comes with respect to active and reactive power but not generally considered in case of total power  

Answer 2

kVAR, kVA and kW sort of represent the same thing, though kW is the total transferred power (taking into account power factor).

For D.C.  kVA = kW as there is no phase difference between current and voltage.

For A.C. signals, kW = p.f. * kVA   where p.f. is power factor

See the sources for the definition of VAR, it is power consumed by a reactive load and also depends on power factor,

Note that you have included the k as a prefix, the actual units are W, VA and VAR.

Answer 3

In electrical theory the simplest formula for power is Apparent Power = Amps x Volts IE P= VA and 1 KVA = 1000VA or Volt Amperes.

In AC circuits the current and voltage are often out of phase (out of step) this variation is known as the power factor or PF often denoted by the term COS (phi) the cosine of the angle between the voltage and the current. (as mentioned in other answer) The equation for single phase AC power now reads Actual Power in Watts = Volts x Amps x PF or P = V x A x Cos (phi)

The formula to find the difference is KVA - KW

KVAR is the reactive power and is the power lost in the reactive component in a simple phasor diagram a triangle is drawn with the 3 sides being the KVA, the KVAR and the KW

The KW is the actual power used The KVA the apparent power and the KVAR the reactive or(lost) power. Please check out the Web site below  

Answer 4

Q is the reactive power expressed in terms of KVAR

P is the real power expressed in W

S is the Apparent power expressed in KVA

by power triangle

(P^2)+(Q^2)=(S^2)