Active Power and Reactive Power
Table of Contents
Active Power and Reactive Power
Difference Between Active Power and Reactive Power
Active Power formula
Reactive Power formula
The fact that active power is the actual power that is dissipated in the circuit is the key distinction between active power and reactive power. Reactive power, on the other hand, is useless energy that only travels between a source and a load. The comparison chart below explains the additional distinctions between active and reactive power.
Only when their current deviates by an angle from the applied voltage do active, apparent, and real power enter the circuit. The right-angled triangle below illustrates the relationship between active, reactive, and apparent power.
Where, S – apparent power
Q – reactive power
P – Active power
Difference Between Active Power and Reactive Power
| Basis for Comparison | Active Power | Reactive Power |
|---|---|---|
| Definition | The active power is the real power which is dissipated in the circuit. | Reactive power is the term for the type of power that oscillates between a load and a source. |
| Measuring Unit | Watts | VAR |
| Represented By | P | Q |
| Causes | Produces heat in heater, light in lamps and torque in motor. | Measures the power factor of the circuit. |
| Measuring Instrument | Wattmeter | VAR Meter |
Definition of Active Power
The active power in a circuit is defined as the power that is dissipated or performing useful work. Watts or megawatts are used to measure it. The capital letter P stands for the active power. The expression yields the circuit’s average power value.
The active power derives the circuit and load.
Definition of Reactive Power
Reactive power is transferred between the circuit’s source and load. So The load is not being helped by this power in any way. Reactive power is denoted by Q and is quantified in VAR. The induction motor, transformer, or solenoids discharge the reactive power that has been stored in the circuit.
Key Differences
- The active power is the real power consumes by the load. Where as, the reactive power is the useless power.
- Voltage, current, and the sine of the angle between them are multiplied to create the active power. In contrast, the reactive power is the result of adding the sine of the angle between the voltage and current and their products.
- The letter P represents the Active power, and the Q represents the reactive power.
- The active power is the real power, and it is measured in watts. While the reactive power is measured in VAR.
- So The active power is what causes the torque that the motor develops, the heat that the heater dissipates, and the light that the lamps emit. The circuit’s power factor is determined by the reactive power.
- The wattmeter measures the active power. And the VAR meter is used for measuring the apparent power.
Conclusion
The circuit’s useful work is carried out by the active power. Additionally, the reactive power does nothing but flow through the circuit.