PFC circuit UC3854 the (High Power Factor Pre Regulator) integrated based on a very SMPS power supply primary part of this circuit’s quality based on active and passive circuits used in power supplies reactive power to minimize go to pay for. PFC circuit input voltage of 240 Volt AC 420 Volt DC output

UC3854 PFC circuit

Worldwide ac/dc switch mode power supplies (SMPS) are a multi billion industry generating $23 billion in the year 2000 and they are continuing to expand. SMPS service applications range from communication and computers through to military uses. One of the leading topics in line-operated power-converter design is to take the power from the grid but not to return it. Ideally, the power converter will present as a purely resistive impedance to the ac source.

This is known as Unity Power Factor (UPF) and it has become an important design issue as a consequence of recent legislation. European legislation restricts the harmonic content for power supplies. International standards are emerging known as the IEC 1000-3 and IEC 555-2.

The benefits of unity power factor are more than legislative compliance. The benefits include greater efficiency, larger power density and improved power quality result in economic benefits to the electricity supplier.

This project involves the design of a 2.4kW Unity Power Factor Rectifier. The converter operates at an input voltage of 240Vac and outputs a regulated 420Vdc.

Explore all details of the project calculations (english) have a separate treasury in these drawings :) protel Calculations.xls UC3854 datasheet files in Microsoft Excel format, Calculations.xls and Inductor Boost Converter Design software (Magnetics)

UC3854 High Power Factor Preregulator

Exhibitor: Matthew Douglas Supervisor: Geoffrey Walker – The UC3854 provides active power factor correction for power systems that otherwise would draw non-sinusoidal current from sinusoidal power lines. This device implements all the control functions necessary to build a power supply capable of optimally using available power-line current while minimizing line-current distortion. To do this, the UC3854 contains a voltage amplifier, an analog multiplier/divider, a current amplifier, and a fixed-frequency PWM. In addition, the UC3854 contains a power MOSFET compatible gate driver, 7.5V reference, line anticipator, load-enable comparator, low-supply detector, and over-current comparator.

• Control Boost PWM to 0.99 Power Factor
• Limit Line Current Distortion To <5%
• World-Wide Operation Without Switches
• Feed-Forward Line Regulation
• Average Current-Mode Control
• Low Noise Sensitivity
• Low Start-Up Supply Current
• Fixed-Frequency PWM Drive
• Low-Offset Analog Multiplier/Divider
• 1A Totem-Pole Gate Driver
• Precision Voltage Reference

Source http://innovexpo.itee.uq.edu.au/2003/exhibits/s362886/ 2.4 kW Unity Power Factor Rectifier UC3854AN 240V AC to 420V DC alternative link:

FILE DOWNLOAD LINK LIST (in TXT format): LINKS-8746.zip