how to find kva?
In the kW to kVA calculations, the kW to kVA conversion formula is -
kW = kVA × PF
Where,
kW is the unit estimating real power.
kVA is the unit estimating apparent power.
PF is the Power Factor.
In the kW to kVA conversion, kW is directly relative to kVA, which implies that-
When kW increments, kVA will increment.
When kW declines, kVA will diminish.
When kVA declines, kW will diminish.
When kVA increments, kW will increment.
In mathematical terms, we can write it as:
kW = kVA x PF
The conversion of kVA to kW; these two units of power are significant to solve many problems in Physics. kVA to kW formula is:
kVA= kW/PF
For example: If the Power factor is 0.2 and kW is 150 then kVA = 150/0.2 = 750 kVA.
To convert kW to kVA; The power units are essential to solve kVA calculations in Physics.
To convert kW to kVA-
kW=kVA×PF
Example: If the Power Factor is 0.2, and kVA is 150 then to convert kW to kVA
kW=150kVA×0.2 = 30kW
Just like kW to kVA conversion, A kilowatt-hour (kWh) is the measure of the energy a circuit working at a kilowatt of power moves through the span of 60 minutes. This unit is equivalent to 3,600,000 joules. The kilovolt-ampere (kVA) is the power rating of a circuit conveying 1,000 volts and an ampere or 1,000 amperes and a volt. A single kilovolt-ampere is comparable to a kilowatt. To change over from kilowatt-hours to kilovolt-amperes, you have to know just the time the circuit takes to move the energy. Measure the time length for which the circuit runs.
The main difference between kW (kilowatt) and kVA (kilovolt-ampere) is the power factor. kW denotes the unit of real power and kVA denotes the unit of apparent power. The power factor, which is defined and known, is, therefore, an approximate value (typically 0.8), and in the kW to kVA calculations, kVA value will always be more than the kW value.
Under industrial as well as commercial generators, kW is most commonly used in the US generators. The majority of the rest of the world mainly uses kVA as the set of generators.
To explain it a bit more, the kW rating is primarily the result of power output a generator can supply based on the engine’s horsepower. kW is figured by the horsepower rating of the times of engine 0.746. For example, if you have a 600 horsepower engine, it has a kW rating of 473. The kilovolt-amperes (kVA) are the generator capacity end. Generator sets are displayed with both ratings usually.
To determine the kW to kVA calculations ratio, the kW to kVA formula below is used.
0.8 (pf) x 750 (kVA) = 600 kW
1. Convert the Real Power in Watts to Apparent Power in kVA (Kilovolt amps).
Solution: S in kilovolt-amps (kVA) which is the apparent power is equal to the P in watts (W) which is the real power, divided by 1000 times the PF:
S(kVA) = P(W) / (1000 × PF)W
Watts divided by 1000 times the power factor is equal to kilovolt-amps.
kVA = kW / (1000 × PF
The Relation between KVA and KW is one the most interesting topics from the Class 11 and 12 Physics part which deals with Electrical concepts and their applications. At a higher level, the relationship between KVA and KW is one of the most talked-about in electrical engineering and electronics engineering. Hence, the relation between KVA and KW finds its relevance in school-level exams as well as higher technical examinations as well.
Hence, students should be ready with all the basic concepts at their fingertips which will ensure that they will be able to answer any questions appearing from the topic of the relation between KVA and KW. Vedantu has come to the rescue and solved all the queries of the students by providing free and necessary learning materials which will ensure that students will be able to grasp important concepts and tips and tricks to make sure they will be able to remember them as well. Here are the points to remember in the relation between KVA and KW:
The formula for finding the required KVA or transformer size for single-phase power is the following:
Volts x Amps / 1,000 = KVA
Based on the equation, one would need to plug in the proper load/output (secondary) voltage and current (amps) to compute for KVA. Note that load voltage is not the same as line voltage, which is also known as primary voltage or input.
Example: Find the KVA or transformer size for load voltage of 120V 1PH and a load current of 50A.
120 x 50 / 1,000 = KVA 6,000 / 1,000 = KVA = 6 KVA
Businesses that require three-phase power need to add an extra component in the formula to arrive at the correct transformer size, i.e., square root of 3 (√3) or 1.732. This figure is a constant found in three phase, as the phases do not generate the same amount of power (simultaneously). Furthermore, three-phase transformers handle three lines of AC power, with each of the three lines 120 degrees out of phase from the other two lines.
With this in mind, the new formula can be found below:
Volts x Amps x √3 / 1,000 = KVA
Example: Find the KVA or transformer size for load voltage of 240 3PH and a load current of 60 amps.
240 x 60 x 1.732 / 1,000 = KVA = 24.94 KVA (or 25 KVA after rounding up)
Computing for the required KVA is not the final step in determining the proper transformer size. Most computations (especially for three-phase loads) do not provide a whole number. As a result, the value must be rounded up, as seen in the sample above. It is best practice to always round up and not down. Next, in order to factor in future expansion and prevent risks associated with accidental overloading, one should add 20 percent of spare capacity. Taking the three-phase sample again, we simply add 20 percent to the rounded figure:
25 KVA + 5 = 30 KVA
