Relation Between KVA and KW

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kVA kW Relation 

KiloVolt-Amperes in short kVA is the unit estimating evident power and KiloWatt in short kW is the unit estimating real power. The connection between kVA and kW are corresponding. kW is the measure of 'actual power' an electrical framework has. This gives you how much power is being changed over into an effective, working yield. kVA, then again is the proportion of 'apparent' power. If kW is the amount of force you can work with, kVA reveals to you the amount that is being used in the framework by and large. On the off chance that the productivity of an electrical framework is excellent, at that point kW would be equivalent to kVA. 

kW to kVA Formula

In the kW to kVA calculations, the kW to kVA conversion formula is -

kW = kVA × PF


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:

kVA And kW Relation for AC And DC Circuits



AC Circuit

Power Factor >1

kW= kVA*PF

DC Circuit

Power Factor=1

kW= kVA

kVA to kW Calculations

The conversion of kVA to kW; these two units of power is 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.

kW to kVA Calculations

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

Convert kWH to kVA

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. 

Difference Between kW and kVA

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

Solved Questions

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)

Fun Facts

  1. A fraction of kVA is only accessed to do any work, and the rest fraction is considered in current.

  2. kW represents the actual power which does the valid work.

  3. When we consider a DC circuit, the kW and kVA are both equal because of the reason that the current does not go out of the phase. But in the case of AC circuits, many differences can be found.

FAQ (Frequently Asked Questions)

1. What is the Power Factor? 

The power factor (pf) is commonly characterized as the proportion between kilowatts (kW) and kilovolt amps (kVA) that are drawn from an electrical load. The pf on the nameplate of a generator relates the kVA to the kW rating both. Generators with higher power factors all more effectively move energy to the connected load, while generators with a lower power factor are not as proficient and result in expanded force costs. The standard power factor for a three-stage generator is generally 0.8. In an electric power framework, a load with a low power factor draws more flow than a load with a high power factor for a similar measure of usable power moved.

2. Why are Generators and also Alternators Determined in kVA and not kW?

The alternator conductors are determined for a clear current, and the protection at an attractive framework is intended for a positive voltage free of p.f. (Cos θ) of the load. Consequently, apparent power estimated in kVA is viewed as the rated power of the alternator. 

The primary manufacturers consider while structuring electrical gadgets and machines which give electric force like transformers, UPS, alternators and generators, etc. are a burden and force factor. As they don't know precisely what the power factor is and which sort of burden will be associated with the gadget and machines. So they design and rate the electrical device based on its maximum output of current that the conductors can safely carry.