Being efficient, these panels maintain the power factor of an electrical system by automatically regulating the reactive power (kVAR) required by inductive loads. This reduces power loss, increases energy efficiency, and lowers electricity bills.
Moreover, by maintaining power factors at desired levels, APFC panels can help reduce voltage drops and improve voltage stability.
There are several electrical components in an APFC panel, including a microcontroller-based automatic power factor correction relay, capacitors, reactors, and other electrical components.
As the microcontroller, capacitors, and reactors monitor, the power factor within a set range is switched on and off to maintain the power factor. For example, capacitor banks are automatically connected during peak hours if the power factor falls below 0.9 (lagging).
Functioning
Here’s how an APFC panel works:
- Through a microcontroller-based power factor correction relay, the APFC panel continuously monitors the power factor of the electrical system.
- The microcontroller calculates the power factor required to maintain the desired level based on the system’s reactive power (kVAR) required by the inductive loads.
- Microcontrollers control capacitors and reactors to maintain the desired power factor by switching them according to the analysis.
- Through the use of contractors or thyristors, the APFC panel controls the switching of the capacitors and reactors, allowing the reactive power to be adjusted quickly and efficiently.
- By detecting faults such as over-voltage, under-voltage, overcurrent, and short-circuits, the APFC panel also protects the electrical system. It isolates the faulty section of the system.
Types
Various types of APFC panels are available, designed to suit different electrical needs. Here’s a list of commonly used APFC panels
- APFC Panels with Fixed Capacitors: These panels are used in electrical systems with stable load profiles with constant reactive power demand. APFC panels with fixed capacitors maintain the desired power factor by switching a fixed bank of capacitors on and off as required.
- Thyristor Switched APFC Panel: This type of APFC panel is used in electrical systems with varying load profiles and fluctuating reactive power demands. In thyristor-switched APFC panels, capacitors are connected through thyristors that switch the capacitors on and off based on the reactive power demand.
- Hybrid APFC Panel: These panels combine fixed capacitors and thyristor-switched APFCs to provide a constant power factor in electrical systems with a variable load profile.
- APFC Panels with Detuned Filter Types: These panels are used when there is harmonic distortion in an electrical system, which can cause equipment failure, resonance, or overheating. A detuned filter-type APFC panel consists of capacitors and reactors that filter out harmonic distortion and maintain a stable power factor.
- Multiple-Step APFC Panel: In electrical systems with high reactive power demands, a multiple-step APFC panel may not be enough to maintain the desired power factor if a single capacitor bank is not sufficient. APFC panels with multiple steps switch on and off capacitor banks according to reactive power requirements, each with a different KVAR rating.
BCH Electrical offer APFC panels with advanced Micro Controller based Power Factor Controller with Self-diagnostic Sensing and Control of Capacitor Bank Stages. This panel consists of capacitor duty contractors for reliable & trouble-free operation.
To manage heat load properly, this thoughtfully designed panel comes with louvres and a cooling fan.
Repercussions
If an electrical system does not have an Automatic Power Factor Correction (APFC) panel, the following consequences can occur:
- Higher Electricity Bills: When an electrical system’s power factor is low, it requires more current to produce the same amount of power.
- Reduced Efficiency: Low power factors can reduce the efficiency of electrical systems by causing energy losses.
- Reduced Equipment Lifespan: Electrical equipment can be damaged by voltage fluctuations caused by excess reactive power within an electrical system.
- Voltage Fluctuations: Inductive loads produce reactive power that can cause voltage fluctuations, which affect equipment operation and system stability.
- Penalties from Utilities: Utilities may penalise customers with low power factors, which results in higher electricity bills.
With improved energy utilisation, APFC panels are a go-to for improving the power factors of an electrical system.
