With the increasing demand for power from the ac line and more stringent limits for power quality, power factor correction has gained great attention in recent years. A variety of circuit topologies and control methods have been developed for the PFC application. International Standards in the area of compliance of a product’s AC mains current harmonics have forced that new power supply design ...

There are various reasons why power factor correction circuit is used in various power supplies in large systems. The PFC (Power Factor Correction) at input stage becomes real necessary when the input power goes above 1kW typically. Recent advances in PFC include interleaving of two out-of-phase circuits to gain many system level advantages. Enough has been discussed about the advantages of int...

Medium and high power switch mode power supplies SMPS (>500W) used in telecommunications stations are normally based on the full-bridge DC-DC converter with isolation transformer. According to the transistors states, the full-bridge converter allows four different switching sates which can be used to control the output voltage of the SMPS, and to perform the power factor corrector (PFC) functio...

Reactive energy and power factor L2 1.1 The nature of reactive energy L2 1.2 Equipment and appliances requiring reactive energy L2 1.3 The power factor L3 1.4 Practical values of power factor L4 Why to improve the power factor? L5 2.1 Reduction in the cost of electricity L5 2.2 Technical/economic optimization L5 How to improve the power factor? L7 3.1 Theoretical principles L7 3.2 By using what...

This thesis focuses on the study, implementation and improvement of a digital controller for a power factor correction (PFC) converter. The development of the telecommunications industry and the Internet demands reliable, cost-effective and intelligent power. Nowadays, the telecommunication power systems have output current of up to several kiloamperes, consisting of tens of modules. The high-e...

New recommendations and future standards have increased the interest in power factor correction circuits. There are multiple solutions in which line current is sinusoidal. In addition, in the recent years, a great number of circuits have been proposed with nonsinusoidal line current. In this paper, a review of the most interesting solutions for single phase and low power applications is carried...

Conventional AC/DC power converters that are connected to the line through full-wave rectifier draws a non-sinusoidal input current. These Harmonic currents flowing through the impedances in the electrical utility distribution system can cause several problems such as voltage distortion, heating, noises. These harmonics distort the local voltage waveform, potentially interfering with other elec...

Harmonic pollution and low power factor in power systems caused by power converters have been a great concern. To overcome these problems several converter topologies and control schemes have been proposed in recent years. This paper is proposed to study the control techniques for such converters to improve the Power Factor (PF) and reduce total harmonic distortion (THD) in the input current wi...