APFC stands for “Automatic Power Factor Correction.” It is a system used in electrical engineering and power distribution to improve the power factor of an electrical load. The power factor is a measure of how effectively electrical power is being converted into useful work output in an electrical system. A low power factor indicates that a significant portion of the electrical power is being wasted as reactive power, which doesn’t contribute to useful work but still needs to be supplied by the utility.

The APFC system works by automatically monitoring the power factor of the electrical load and then taking corrective measures to adjust it to a desired level, typically close to 1 (unity power factor). It does this by controlling the connection and disconnection of power factor correction capacitors or reactors in the electrical circuit.

Key components and features of an APFC system include:

1. Sensors: Sensors or power factor meters are used to continuously monitor the power factor of the electrical load.

2. Controller: The controller receives input from the sensors and calculates the required amount of power factor correction.

3. Capacitors/Reactors: The APFC system includes capacitors (for leading power factor correction) or reactors (for lagging power factor correction) that are switched in or out of the circuit as needed to improve the power factor.

4. Switchgear: Electrical switchgear and contactors are used to connect or disconnect the capacitors/reactors as directed by the controller.

5. Automatic Operation: APFC systems are designed to operate automatically, ensuring that the power factor is continuously adjusted to maintain efficiency and avoid penalties from utilities for a low power factor.