Explaining Power Factor Correction and Its Importance

In the field of power electronics, PFC (Power Factor Correction) serves as an important mechanism that improves electrical systems' performance and general effectiveness. PFC has a set of techniques to increase the power factor coefficient for electric circuits. This, in turn, maximises the use of energy and reduces wastage. Acknowledging PFC and its role is the most important issue in guaranteeing electrical infrastructure's smooth functioning and durability. In this blog, we will help you understand more about what power factor correction is in electrical engineering, along with its significance.

What is Power Factor Correction (PFC)?

Power Factor Correction (PFC) refers to techniques used in power supply systems to improve the power factor (PF). It is commonly used in computer power supplies to improve PF. PF determines power consumption efficiency, with higher PF values suggesting more efficient use.

Types of Power Factor

The power factor in a circuit can manifest in three types: either by leading, by lagging, or by unity, depending on the circuit.

1. Leading Power Factor: This phenomenon occurs when the current in the circuit is ahead of the voltage pointer or in purely capacitive circuits. An advanced power factor leads to the positive phase angle between the current and voltage, with a value of -1 to 0.
2. Lagging Power Factor:  A lagging power factor outlines a situation where the current lags behind the voltage, typically observed in purely inductive circuits. Here, the phase angle between current and voltage is minus, with the power factor rating from 0 to 1.
3. Unity Power Factor: In circuits with in-phase current and voltage, the power factor equals 1. This happens in ideal cases with no reactive power load on the circuit.

Why Power Factor Correction Is Necessary? 5 Key Reasons

PFC (Power Factor Correction) is adopted for the purpose of improving the performance of electrical systems. This formula provides essential benefits for businesses and organisations. Here are the reasons why PFC is indispensable:

• Reduced Carbon Footprint: PFC can perform reactive power locally; thus, there is no large system demand. This property promotes energy efficiency and environmental sustainability. In addition, PFC reduces dependence on the main power, thus enhancing the longevity of the electrical grid, consequently resulting in a low carbon footprint and good corporate eco-attributes.
• Increased Load Capacity: Having reactive power eliminated by PFC modules enables a more extensive usage of active power (kW) without the commonly associated upsurge, merely an overload risk. This flexibility allows businesses to increase operational capacity at more affordable costs, as it does not involve expensive infrastructure upgrades and, therefore, becomes financially viable as a means of meeting rising energy demands.
• Avoidance of Penalties: In addition, people using power-hungry appliances that consume a lot of power despite maintaining high power factors are often charged more for electricity. PFC addresses this so that the power factor is raised beyond penalty thresholds, gaining significant amounts of energy cost reduction and the availability of organised power usage.
• Enhanced Voltage Stability: Voltage drops caused by a power factor below the optimal may lead to equipment damage and escalation of maintenance costs. The voltage drop Challenge from the PFC is eliminated, thus leading to stable voltage levels and overall high efficiency and safety across the electrical system.
• Reduced Maximum Availability Requirement: PCF-based deployment, therefore, decreases the peak power draw in the whole system, which helps to avert the stress put on the power sources and to reduce the instances where the system is interrupted due to electrical malfunctions or outages. This pre-emptive measure minimises the amount of downtime and, by extension, the costs in that regard, thus ensuring that regular business proceedings are not interrupted.

Power Factor Correction becomes a crucial factor in developing effective energy management that gives various advantages such as monetary savings, greater operational resilience and environmental responsibilities. Business owners should adopt practices that promote sustainability and operational efficiency with the goal of fully incorporating PFC solutions that help them improve their electrical infrastructure.

How Do You Calculate Power Factor Correction?

Choosing the appropriate PFC equipment involves a systematic approach, requiring expertise in the following steps:

Step 1: Use of Active and Passive Power Factor Correction Techniques

The first step is to calculate the required (Qc in kvar) based on its reactive power (cos φ) and apparent power (S).

Qc can be calculated using the formula Qc = P (tan φ – tan φ‘), derived from the diagram, where:

• Qc=Capacitor bank power (kVAr).
• P = power in active mode (kW)
• tan φ = tan of pushing angle considering the uncompensated phase shift.
• φ̂ ‛ = tan φ ‛ = tangent of phase shift angle after compensation.

φ and tan φ parameters can be obtained from meeting billing data or from the direct measurements taken at the installation site.

Step 2: Choice Of the Compensation System

The interface capacitance can be set based location-wise (entire grid) or by sector (section by section).

Factors influencing location choice include:

• Overall objectives (e.g., avoiding penalties on reactive energy, relieving transformers)
• Operating mode (consistent or varying that shifts)
• Impacts of capacitors predictable on network characteristics.
• Installation costs

Step 3: Decision on Form of Remuneration

Different compensation types are utilised based on performance requirements and control complexity:

• Fixed: Interconnect a variable capacitor bank in the form of a fixed valve.
• Automatic: Link steps to make the system to be flexible and have the capability to control the energy output.
• Dynamic: Well-suited for balancing lumpy loaders.

Step 4: Converters and FRAs must be designed to accommodate the variations in operating conditions and harmonics.

Operating conditions significantly affect capacitor lifespan, necessitating consideration of parameters such as: 

• Ambient temperature (°C)
• Induce expected over-current by the impact of voltage disturbances.
• Maximum switching operations annually
• Desired lifespan

Certain loads lead to the prevalence of harmonics in the power network, which is detrimental to capacitors. In this context, the harmonic effects should be assessed because it ensures the optimal performance and the life span of capacitors.

Also Read - DIFFERENCE BETWEEN ACTIVE POWER, REACTIVE POWER AND APPARENT POWER

Conclusion

In a world where every watt counts, Power Factor Correction emerges as an essential tool for transforming energy waste into efficiency. With its ability to optimise power usage and reduce unnecessary losses, PFC has become the pillar of sustainable electrical systems. Adapt PFC and illuminate the path to a greener, more efficient future.

At Schneider eShop, you can discover different types of PFC solutions that are developed in such a way as to increase power factor, decrease losses, and reduce operational costs. Give your home or business smart energy solutions from Schneider Electric and get on the track of greener and more efficient energy. Visit Schneider eShop today and discover PFC as a smart solution for the future in immediate terms.