The significance and function of power factor

2021-03-30 15:36:49

The ratio of the active Power consumed by the circuit to the total Power supplied by the Power source is called the Power Factor (PF).

 

The higher the power factor, the less nonfunctional amount is transferred between the power supply and the circuit. Low power factor indicates high reactive power, which reduces the utilization rate of equipment and increases the loss of line power supply. Therefore, in power engineering, the higher the power factor, the better. Improving the power factor can not only improve the utilization rate of power system and power enterprise equipment, so as to improve the power generation capacity under the same conditions of power generation equipment, but also reduce the loss of electric energy and improve the quality of electricity. Therefore, the power factor is a very important technical measure to save electricity.

 

1, Improve the natural power factor of electrical equipment, such as avoiding equipment light load, no-load operation

 

2, Reduce nonlinear components equipment; Reasonable configuration of transformer, appropriate choice of capacity; Improve distribution line layout, avoid twists and turns and so on.

 

3. Add reactive power compensation devices, such as capacitors (usually the reason that affects the power factor is the inductive load). In the inductive load, the reactive power of the capacitor can be used to compensate the reactive power of the inductive load, thus reducing or even eliminating the original energy exchange between the inductive load and the power supply. In a pure resistance circuit, the current in the load is in phase with the voltage. The current in the load of the pure inductor lags behind the voltage of 90 °, while the current of the pure capacitor is ahead of the voltage of 90 °. The current in the capacitor and the current in the inductor differ 180 °, which can cancel each other out. Most of the load in the power system is inductive, so the total current will lag behind the voltage by an Angle. If the shunt capacitor is paralleled with the load, the current of the capacitor will offset part of the inductive current, thus reducing the total current and increasing the power factor.