What’s the PFC of power supplies?

PFC (Power Factor Correction) in power supplies is a technology used to improve power efficiency and reduce energy waste. Its core goal is to optimize the efficiency of power utilization by the power source, making it more in line with the power supply standards of the grid, while reducing interference with the grid.

1. What is power factor
-Power Factor is an indicator that measures the efficiency of electricity utilization, ranging from 0 to 1. Simply put:
-Active power: The electrical energy actually consumed by an appliance and converted into useful work (such as heating or driving a motor).
-Reactive power : Electrical energy that is repeatedly cycled and unused in a circuit (such as losses caused by charging and discharging capacitors and inductors).
-Power factor=active power/apparent power. The closer the power factor is to 1, the higher the energy utilization efficiency.

2. Why do we need PFC
Traditional power supplies (especially switch mode power supplies) may have current waveforms that are not synchronized with voltage waveforms when not calibrated, resulting in:
-Low power factor (such as 0.5-0.7) results in a significant waste of electrical energy.
-Harmonic pollution: Distortion of current waveform generates high-frequency harmonics, which interfere with other equipment in the power grid (such as causing transformer overheating and electronic equipment abnormalities).
-Not compliant with regulations: Many countries (such as the European Union and China) require electronic devices to have PFC functionality.
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3. Types of PFC
(1) Passive PFC
-Principle: Use passive components such as inductors and capacitors to adjust the current phase to approach the voltage phase.
-Advantages: Low cost, simple structure, and high reliability.
-Disadvantages: Limited power factor improvement (usually 0.7-0.8), large size, suitable for low-power scenarios (such as small household appliances).
(2) Active PFC (Active PFC)
-Principle: By dynamically adjusting the current waveform through control circuits (such as Boost boost chopper circuits) and IC chips, it synchronizes with the voltage.
-Advantages:
-The power factor can reach above 0.95, approaching the ideal value.
-Reduce harmonic pollution and support wide voltage inputs (such as 100V-240V).
-Improve the overall efficiency of the power supply, suitable for high-power devices such as PC power supplies and servers.
-Disadvantages: High cost and complex circuit.
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4. The Importance of PFC
-Energy saving and Environmental Protection: Reduce reactive power loss and lower power grid load.
-Compliant with certification standards: For example, 80 PLUS certification requires high power factor, and active PFC is a standard configuration for high-end power supplies.
Stable power grid * *: Suppress harmonics and avoid interference with other devices (such as audio noise and flashing lights).

Haifyer has launched this power supply with a PFC value of up to 0.95, perfectly meeting the high-end customers’ demand for power performance and providing superior power stability and efficiency.Press below picture to see the details.