## Monday, May 13, 2024

Power factor explained | Active Reactive Apparent Power correction

Unlock the secrets of power factor correction and optimize energy efficiency in AC circuits with our comprehensive guide! In this video, we dive deep into understanding power factor and its impact on energy usage. Discover how inductive loads affect power factors and why addressing them is crucial for reducing wastage. Learn how to calculate power factor and identify the need for power factor correction to enhance efficiency. Explore step-by-step instructions for implementing power factor correction by adding capacitors in parallel to the circuit. Follow along as we demonstrate calculations to determine the ideal capacitor size and capacitance for optimal power factor correction. Get practical insights into implementing power factor correction techniques, including the installation of a capacitor bank. Join us on this journey to improve power factors and unlock greater energy efficiency in your electrical systems! Don't miss out – hit the like button, share with your friends, and subscribe for more educational content on electrical engineering topics. Boost your knowledge and efficiency today!

What is Active Power: (P)

Active Power is the actual power which is really transferred to the load such as transformer, induction motors, generators etc and dissipated in the circuit.

Alternative words used for Real Power (Actual Power, True Power, Watt-full Power, Useful Power, Real Power, and Active Power) and denoted by (P) and measured in units of Watts (W) i.e. The unit of Real or Active power is Watt where 1W = 1V x 1A.

Active Power in DC Circuits:

In DC Circuits, 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 frequency (f) or Power factor in DC Circuits.

Active Power in AC Circuits:

Active Power in AC Circuits:

But the situation in Sinusoidal or AC Circuits is more complex because of phase difference (Î¸) between Current and Voltage. Therefore average value of power (Real Power) is P = VI CosÎ¸ 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.

What is 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 actually absorbed and returned in load due to its reactive properties is referred to as reactive power.

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

Reactive power is given by Q = V I SinÎ¸ which can be positive (+ve) for inductive loads and 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 produced by 1A x 1V is known as the unit of Reactive Power.

Must read: Is Reactive Power Useful?

Reactive Power Formulas:

Q = V I SinÎ¸

Reactive Power = √ (Apparent Power2– True power2)

VAR = √ (VA2 – P2)

kVAR = √ (kVA2 – kW2)

Where:

Î¸ = Phase angle

What is 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 which is denoted by (S) and measured in units of Volt-amp (VA).

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

S = √ (P + Q2)

Apparent Power = √ (True power2 + Reactive Power2)

kVA = √kW2 + kVAR2

What is Complex Power? (S = P+jQ or S=VI*)

The Complex sum of Real Power (P) and Reactive Power (Q) is known as Complex Power which can be expressed like S = P+jQ and measured in terms of Volt Amps Reactive (generally in kVAR).

It may also be expressed as S=VI* where “I*” is the conjugate of the complex current I. This current “I” flows through a reactive load Z caused by the Voltage.

Complex Power Formulas:

Z = R – jXC

I = IP + jIQ

CosÎ¸ = R / |Z| (leading)

I* = IP – jIQ

S = P – jQ

A Capacitive Load provides Leading VARS (i.e. it eliminates VARS and improves the overall power factor of the system). That’s why capacitors are used to correct and improve the power factor.

Z = R + jXL

I = IP – jIQ

CosÎ¸ = R / |Z| (lagging)

I* = IP + jIQ

S = P + jQ

Where:

Z = Impedance

R=Resistance

XL = Inductive Reactance

XC = Capacitive Reactance

CosÎ¸ = Power Factor

P = Active Power

S = Apparent Power

Q = Reactive Power

Role of Active Power and Reactive Power

There is an important relationship between active and reactive power and the post below will help to understand that why active power (P) is called true power and reactive power (Q) is called imaginary power. Explanations given in this article are rarely available in the books.

Power factor explained | Active Reactive Apparent Power correction

Unlock the secrets of power factor correction and optimize energy efficiency in AC circuits with our comprehensive guide! In this video, we dive deep into understanding power factor and its impact on energy usage. Discover how inductive loads affect power factors and why addressing them is crucial for reducing wastage. Learn how to calculate power factor and identify the need for power factor correction to enhance efficiency. Explore step-by-step instructions for implementing power factor correction by adding capacitors in parallel to the circuit. Follow along as we demonstrate calculations to determine the ideal capacitor size and capacitance for optimal power factor correction. Get practical insights into implementing power factor correction techniques, including the installation of a capacitor bank. Join us on this journey to improve power factors and unlock greater energy efficiency in your electrical systems! Don't miss out – hit the like button, share with your friends, and subscribe for more educational content on electrical engineering topics. Boost your knowledge and efficiency today!

What is Active Power: (P)

Active Power is the actual power which is really transferred to the load such as transformer, induction motors, generators etc and dissipated in the circuit.

Alternative words used for Real Power (Actual Power, True Power, Watt-full Power, Useful Power, Real Power, and Active Power) and denoted by (P) and measured in units of Watts (W) i.e. The unit of Real or Active power is Watt where 1W = 1V x 1A.

Active Power in DC Circuits:

In DC Circuits, 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 frequency (f) or Power factor in DC Circuits.

Active Power in AC Circuits:

Active Power in AC Circuits:

But the situation in Sinusoidal or AC Circuits is more complex because of phase difference (Î¸) between Current and Voltage. Therefore average value of power (Real Power) is P = VI CosÎ¸ 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.

What is 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 actually absorbed and returned in load due to its reactive properties is referred to as reactive power.

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

Reactive power is given by Q = V I SinÎ¸ which can be positive (+ve) for inductive loads and 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 produced by 1A x 1V is known as the unit of Reactive Power.

Must read: Is Reactive Power Useful?

Reactive Power Formulas:

Q = V I SinÎ¸

Reactive Power = √ (Apparent Power2– True power2)

VAR = √ (VA2 – P2)

kVAR = √ (kVA2 – kW2)

Where:

Î¸ = Phase angle

What is 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 which is denoted by (S) and measured in units of Volt-amp (VA).

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

S = √ (P + Q2)

Apparent Power = √ (True power2 + Reactive Power2)

kVA = √kW2 + kVAR2

What is Complex Power? (S = P+jQ or S=VI*)

The Complex sum of Real Power (P) and Reactive Power (Q) is known as Complex Power which can be expressed like S = P+jQ and measured in terms of Volt Amps Reactive (generally in kVAR).

It may also be expressed as S=VI* where “I*” is the conjugate of the complex current I. This current “I” flows through a reactive load Z caused by the Voltage.

Complex Power Formulas:

Z = R – jXC

I = IP + jIQ

CosÎ¸ = R / |Z| (leading)

I* = IP – jIQ

S = P – jQ

A Capacitive Load provides Leading VARS (i.e. it eliminates VARS and improves the overall power factor of the system). That’s why capacitors are used to correct and improve the power factor.

Z = R + jXL

I = IP – jIQ

CosÎ¸ = R / |Z| (lagging)

I* = IP + jIQ

S = P + jQ

Where:

Z = Impedance

R=Resistance

XL = Inductive Reactance

XC = Capacitive Reactance

CosÎ¸ = Power Factor

P = Active Power

S = Apparent Power

Q = Reactive Power

Role of Active Power and Reactive Power

There is an important relationship between active and reactive power and the post below will help to understand that why active power (P) is called true power and reactive power (Q) is called imaginary power. Explanations given in this article are rarely available in the books.