PF, Active power, Reactive power are professional terms in Power System. We often need to set these important parameters according to requirement from power system. Many people are a little bit confused about them. Today we will explain them further and make them more clear.
PF
PF is abbreviation of Power Factor (cosφ). It is the cosine of the angle between the current and the voltage phase difference (usually the current lags) in AC circuit. To many people who don’t know power system, it is difficult to understand the meaning of lagging or leading. Before we can learn this, several related terms needs to be referred to. below.
Active Power
Power contains active power and reactive power. , the instantaneous power of AC current is not a constant value, the average value of power in a cycle is called active power, which refers to the power consumed by the resistance load in the circuit, the symbol of active power is represented by P, and the unit is watt (W), Kilowatt (kW).
What’s resistance load?
In our surroundings, like light, electrical stove, resistance etc. which transform 100% energy into heat or light belong to resistance load. There is no phase angle between voltage and current.
Reactive Power
Reactive power contains Inductive reactive power and capacitive reactive power. Reactive power is used to establish magnetic field when electrical components such as inductors and capacitors work. Energy is transformed into magnetic field.
Inductive reactive power
Current wave leads voltage wave . Inductive reacitve power is used to create magnetic field. Inductive load consumes inductive reacitve power.
Capacitive reactive power
Current wave lags voltage wave . Simply speaking, there is no sudden change in voltage during charging and discharging for capacitive reactive power , and the corresponding power factor is negative. Capacitive reactive power can be used when Grid voltage is too high.
PF
Power Factor (cosφ) is the cosine of the angle between the current and the voltage phase difference (usually the current lags) in an AC circuit
The higher the power factor, the higher the utilization of electrical energy. The highest power factor is 1, which means that the phase difference is zero, and all the electric energy is consumed by the pure resistance load; the lowest power factor is 0, which means that the phase difference is 90 degrees, all the electric energy is wasted on the line, and is not used by the load at all.
The value range of the power factor is: -1~+1