**(1)**

**Real Power: (P)**

Alternative words used for Real Power (Actual
Power, True Power, Watt-full Power, Useful Power, Real Power, and Active Power)

In a DC Circuit, power supply to the
DC load is simply the product of Voltage across the load and Current flowing
through it i.e., P = V I. because in DC Circuits, there is no concept of phase
angle between current and voltage. In other words, there is no Power factor in
DC Circuits.

But the situation is Sinusoidal or AC
Circuits is more complex because of phase difference between Current and
Voltage. Therefore average value of power (Real Power) is P = VI Cosθ is in
fact supplied to the load.

In AC circuits, When circuit is pure
resistive, then the same formula used for power as used in DC as P = V I.

You may also read about Power Formulas in DC, AC Single Phase and and AC Three Phase Circuits.

**Real Power formulas:**

P = V I (In
DC circuits)

P = VI Cosθ (in
Single phase AC Circuits)

P = √3 V

_{L}I_{L}Cosθ or (in Three Phase AC Circuits)
P = 3 V

_{Ph}I_{Ph}Cosθ
P = √ (S

^{2}– Q^{2})^{ or}
P =√ (VA

^{2 }– VAR^{2}) or^{ }
Real or True power = √ (Apparent Power

^{2}– Reactive Power^{2}) or
kW = √ (kVA

^{2}- kVAR^{2})**(2) Reactive Power: (Q)**

Also known as (Use-less Power, Watt
less Power)

The powers that continuously bounce
back and forth between source and load is known as reactive Power (Q)

Power merely absorbed and returned in
load due to its reactive properties is referred to as reactive power

The unit of Active or Real power is
Watt where 1W = 1V x 1 A.

Reactive power represent that the
energy is first stored and then released in the form of magnetic field or
electrostatic field in case of inductor and capacitor respectively.

Reactive power is given by Q = V I Sinθ
which can be positive (+ve) for inductive, negative (-Ve) for capacitive load.

The unit of reactive power is
Volt-Ampere reactive. I.e. VAR where 1 VAR = 1V x 1A.

In more simple words, in Inductor or
Capacitor, how much magnetic or electric field made by 1A x 1V is called the
unit of reactive power.

**Reactive power formulas:**

Q = V I Sinθ

Reactive Power

^{ }=√ (Apparent Power^{2}- True power^{2})
VAR =√ (VA

^{2 }– P^{2})
kVAR = √ (kVA

^{2}- kW^{2})**(3) Apparent Power: (S)**

The product of voltage and current if
and only if the phase angle differences between current and voltage are
ignored.

Total power in an AC circuit, both
dissipated and absorbed/returned is referred to as apparent power

The combination of reactive power and
true power is called apparent power

In an AC circuit, the product of the
r.m.s voltage and the r.m.s current is called

*apparent power*.
It is the product of Voltage and
Current without phase angle

The unit of Apparent power (S) VA i.e.
1VA = 1V x 1A.

When the circuit is pure resistive,
then apparent power is equal to real or true power, but in inductive or
capacitive circuit, (when Reactances exist) then apparent power is greater than
real or true power.

**Apparent power formulas:**

S = V I

Apparent Power = √ (True
power

^{2}+ Reactive Power^{2})
kVA = √kW

^{2}+ kVAR^{2}

**Also Note that;**
Resistor absorbs the real power and
dissipates in the form of heat and light.

Inductor absorbs the reactive power
and dissipates in the form of magnetic field

Capacitor absorbs the
reactive power and dissipates in the form of electric or electrostatic filed**∴**These all quantities trigonometrically related to each other as shown in below figure.

*Click image to enlarge*

For more Clearance and explanation., i used Lays Chips and Beer Analogy for Real or True Power, Reactive Power , Apparent power and power factor

*Lays Chips Analogy of Real or True Power, Reactive Power, Apparent power & power factor**Click image to enlarge**Beer Analogy of Active or True power, Reactive power, Apparent Power and Power factor.*

- Power Factor
- Causes of low Power Factor
- Disadvantages of Low Power Factor
- Power Factor improvement Methods with Their advantages & Disadvantages
- Advantages of Power factor improvement and Correction
- How to Calculate the Suitable Capacitor Size in Farads & kVAR for Power factor Improvement (Easiest way ever)
- How to Convert Capacitor Farads into kVAR and Vice Versa (For Power factor improvement)

The analogy with the beers and the chips are simply awesome!!!! specially the one with the beers. Can I use the beer image for one of my presentations? how can I get this image? thanks in advance.

ReplyDeleteYou are Welcome dear

ReplyDeleteAwesome

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