Power Factor Correction Applications Research Articles

Employing various topologies to improve the interleaved boost converters performance

In recent years, there has been a significant amount of literature concerning high step-up DC-DC converters. Whereas the voltage level needs to be raised to a higher value so that the DC conversion can meet the AC mains value. A boost converter is the most popular circuit in the field, but because of its drawbacks, employing it is limited. Interleaved boost converters have attracted considerable attention and are a promising solution for high-power step-up and power factor correction applications. To demonstrate the importance of this topology, a comparison has been made with single-switch converters. For this reason, this paper classifies the topologies into two main categories based on the number of main switching elements: Single-switch and interleaved boost converters. Then, each category was classified, including the conventional and the modified types, to cover the effect of adding voltage multiplier cells, coupled inductors, and a combination of coupled inductors and voltage multiplier cells. Each converter’s performance was evaluated by comparing the voltage gain of each unit. Also, this paper highlighted these converters’ essential characteristics, topological strategies, benefits, and demerits to clarify the differentiating solutions. Additionally, this work presents the difficulties or directions for developing novel topologies.

Stabilization of DC‐link voltage in single‐phase AC/DC converter with power factor correction using predictive control algorithm

SummaryThis paper proposes a power factor correction (PFC) method in a single‐phase AC/DC converter using a predictive control algorithm (PCA) through a boost DC/DC converter. The minimum value of the DC‐link capacitor has been evaluated on the DC distribution side for stable operation of the converter. The proposed technique can be applied to the cascade connection of the converters, that is, the uncontrolled rectifier with boost converter and load. The value of the minimum capacitance is obtained as a function of the reference voltage of the DC‐link capacitor, the frequency of the supply, the input power, and the maximum DC‐link voltage. The proposed design is applied to control the boost converter for PFC applications using PCA at the minimum DC‐link capacitor value. The calculated value of DC‐link capacitance has been reduced to a greater extent as compared to the conventional calculation of DC‐link capacitance. The converter operation with the designed value of DC‐link capacitance has been verified through the MATLAB and Typhoon Simulink environment, and an experimental prototype model is used for the validation by using the FPGA based Typhoon HIL‐402 kit.

Unequal Duty-Ratio Feedforward Control to Extend Balanced-Currents Input Voltage Range for Series-Capacitor-Based Boost PFC Converter

In this letter, the series-capacitor-based boost power factor correction (PFC) converter (or called the voltage doubler PFC converter) is studied. It possesses the voltage doubler and intrinsic current balancing characteristics only when their equal duty ratios are larger than 0.5. Thus, for PFC application, the balanced-currents input voltage should be smaller than the quarter (1/4) output dc voltage. To extend the balanced-currents input voltage range, the unequal duty-ratio feedforward control is proposed in this letter. For the case of dc output voltage 400 V, the maximum input voltage with balanced inductor currents increased from 100 V (the quarter output dc voltage) to 200 V. The proposed control method is implemented in the field programmable gate array chip to evaluate its performance.

Power Factor Correction Application Based on Independent Double-Boost Interleaved Converter (IDBIC)

In this paper, a Power Factor Correction (PFC) application, based on the novel power stage topology named Independent Double-Boost Interleaved Converter (IDBIC), has been analyzed. The novelty of the proposed PFC rectifier is based on the sum of capabilities, such as supplying three independent output voltage levels with interleaved operation at the input and high voltage gain. The hardware used within this application consists of an AC input L-C-L filter, a single-phase bridge rectifier, the IDBIC power stage, output capacitors group and a group of variable high-power rheostats (resistors) group as DC load. The main purpose of the carried study was to highlight the advantages and disadvantages of the novel power stage topology in the context of a green and modern AC to DC conversion solution. Nowadays, a high level of the efficiency and power factor have become a mandatory feature for the AC to DC conversion solutions to satisfy the international electrical standards. Thus, considering the modern electrical standards and recommendations, the current study tries to better depict the working steps and principles of the modern power stage topology within an AC to DC conversion application. The behavior of the considered power stage described in different detailed working steps (such as the Discontinuous Conduction Mode and Continuous Conduction Mode) may help understand how the energy conversions process of AC to DC becomes more efficient. The high output voltage gain of the considered power stage is the key feature in the Power Factor Correction process. With such a feature, the AC to DC conversion solution/application can also operate at lower input AC voltages (such as 90 [V] and 110 [V]). The proposed solution can be successfully used in the electric vehicle (automotive field) and high-power electrical traction (e.g., trains, high power electrical machines and drives). The same solution can also be used successfully in fast battery charging applications and chemical electrolysis processes.

Power Factor Correction Using a Series Active Filter

Abstract: Power factor correction (PFC) for single-phase diode rectifiers utilising a series active filter is demonstrated in this project at a minimal cost. When compared to the typical PFC, the suggested PFC has reduced power device ratings requirements, which results in cheaper costs and improved efficiency. It can also eliminate the requirement for a large inductor in the typical PFC, making it more compact. This study examines the proposed PFC's topology, operating principle, and application concerns. The control approach and simulation results are presented in detail. Prototypes of 1-kW are made and the experimental findings are shown to verify the theoretical analysis. Index Terms: Harmonic resonance, hybrid active filter, industrial power system.

A Six-Level Flying Capacitor Multilevel Converter for Single-Phase Buck-Type Power Factor Correction

This article investigates behavior of flying capacitor multilevel (FCML) converters in single-phase buck-type power factor correction (PFC) applications. Recent developments in FCML converters using gallium nitride (GaN) transistors are leveraged to improve power density of a single-phase 240 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{V}_{\text{RMS}}$</tex-math></inline-formula> ac to direct 48 V dc conversion stage in data center power delivery applications. Here, we experimentally demonstrate this concept in a digitally controlled six-level FCML converter hardware prototype. The experimental prototype can deliver 4.5 A average output current at 48 V, resulting in 216 W output power. A key contribution of this article is experimental demonstration of an FCML buck converter in a single-phase PFC application where the flying capacitor voltages follow fractions of the rectified input voltage by swinging at twice-line frequency.

Bridgeless Boost Converter with an Interleaving Manner for PFC Applications

Power quality is a critical issue in power systems. This paper proposes a bridgeless boost converter to increase the power factor of power systems using a utility line source for raising power quality. To reduce input and output current ripple, an interleaving manner is adopted in the proposed power system. When the interleaving bridgeless boost converter is used to implement power factor correction (PFC), it needs two bridgeless boost converters to process power during one switching cycle. In order to simplify the proposed bridgeless boost converter, two sets of switches in the conventional bridgeless boost one are integrated to reduce component counts. With this approach, the proposed bridgeless boost converter uses four switches to implement PFC features. Therefore, the proposed boost converter can increase conversion efficiency and decrease component counts, resulting in a higher conversion efficiency, lower cost and more simplicity for driving circuits. Finally, a prototype with a universal input voltage source (AC 90 V~265 V) under an output voltage of 400 V and a maximum output power of 1 kW has been implemented to verify the feasibility of the proposed bridgeless boost converter.

A Class-E-Based Resonant AC-DC Converter With Inherent PFC Capability

This paper investigates the use of the class-E inverter for power factor correction (PFC) applications. Analytical and state-space models are derived showing the class-E inverter's capability of achieving inherent PFC operation with a constant duty cycle. The inherent PFC operation limits the controller responsibility to the regulation of the output voltage, which is key for resonant converters with challenging control. A converter incorporating a diode bridge, a class-E inverter, and a class-D rectifier is presented for the PFC stage in single-phase offline converters. A prototype is designed to validate the analysis and presented design method. The prototype operates with zero-voltage switching (ZVS) across the load range and achieves up to 211 W of output power at an efficiency of 88%, with an inherent power factor of 0.99 and a total harmonic distortion (THD) of 8.8 %. Frequency modulation is used to achieve lower output power down to 25 W, with a power factor of 0.95, THD of 28 %, and an efficiency of 88 %.

A Carrier-Based Discontinuous PWM Method With Varying Clamped Area for Vienna Rectifier

The three-level Vienna rectifier is an attractive topology for power factor correction applications. However, for practical high-frequency applications, the nonlinearity caused by snubber circuit and parasitic capacitance of Vienna rectifier's switching device will distort input current. This paper proposes a carrier-based discontinuous space-vector modulation (CB-DSVM) method with varying clamped area for Vienna rectifier in high switching frequency applications. The equivalent circuit of Vienna rectifier considering the nonlinear factors is built and the effect of pulse shaping around current zero-crossing point is investigated. The voltage errors caused by the nonlinearity of switching device will distort terminal voltage, which mainly appears at the zero-crossing time. A DSVM method with the fixed clamped area around the zero-crossing point is proposed to reduce the voltage errors and then the simplified CB-DSVM method with varying clamped area by adding a clamped factor to the judging conditions is further studied, which will reduce low-order harmonics of the CB-DSVM method. Simulations and experiments are carried out in a 600 W Vienna rectifier platform, which demonstrates the validity of the proposed method. Compared with the CB-SVM method, the proposed CB-DSVM method with varying clamped area has comparative neutral-point voltage balancing ability and better input current quality.

Adaptive Sliding Mode Based Loss-Free Resistor for Power-Factor Correction Application

The emulation of virtual resistance finds various applications in the power processing industry. This paper proposes a novel notion of adaptive sliding mode based loss free resistor (ASLFR). This is achieved by allowing the input power of the power-out power-in ( POPI ) system to vary, in order to accommodate the load demands. In this paper, the concept is illustrated for power-factor correction (PFC) applications. The ASLFR is used to achieve the dual purpose of harmonics-free rectification along with excellent system response under load and line transients. The scheme serves itself as an efficient single-stage PFC solution. A generic mathematical formulation of the scheme is presented, which can be used for different converters. Then on, a boost topology, operating in continuous conduction mode, is chosen to demonstrate theoretical developments and to showcase the effectiveness of the scheme. The robustness of the proposed controller to any line or load variation is established. A fast voltage recovery with almost no undershoot/overshoot is achieved at transients by using the proposed controller. Additionally, a qualitative analysis is provided to demonstrate the expediency of the proposed ASLFR. The theoretical claims are well supported by simulation as well as experimental results.

Design and Implementation of Three-Phase Current Sensorless Control for PFC Bridge Converter With Considering Voltage Drops of Power Semiconductors

Three-phase bridge converter is popular in ac-dc power conversion. The conventional sensor control with inner current loop and outer voltage loop is often used to control the three-phase bridge converter. Many three-phase sensorless control methods had been proposed to control the bridge converter with considering the inductance and inductor resistance. In this paper, the voltage drop of the power semiconductor is first considered in the proposed three-phase current sensorless control method. At first, the dynamic behaviors of three-phase bridge converter for power factor correction (PFC) applications are studied, and its equivalent three-switch model is developed. Based on this developed model, three-phase current sensorless control with only voltage controller is proposed. Additionally, the voltage-loop transfer function of PFC bridge converter controlled by the proposed method is modeled, and the result is helpful to obtain the controller parameter. The proposed control method is implemented on the DSP-based platform for evaluation. Finally, the provided simulation and experimental results demonstrate the performance of the proposed method.

Single-Phase Single-Stage Isolated ZCS Current-Fed Full-Bridge Converter for High-Power AC/DC Applications

In this paper, a single-phase single-stage isolated zero current switched (ZCS) current-fed full-bridge ac/dc converter is proposed for IGBT-based high-power power factor correction (PFC) applications. By adding an additional commutation path and few resonant components, ZCS operation is realized for all IGBTs. The conduction loss is also lowered by the additional path. Furthermore, the control strategy for the proposed converter is compatible with that developed for traditional PFC converter. In this paper, the topology derivation and circuit operational analysis are given. The control strategy is introduced. A 3-kw prototype is developed and tested to verify the circuit functionality. Finally, the efficiency performance is investigated and comparison is made to show the advantages of the topology.

Charge Current Controlled Single Phase Integrated Switched Mode Power factor Correction Converter

Integration of converters reduces the number of control switches and increases the power handling capacity. Charge current control have the features like fast dynamic response, design of compensator is easy and low switching noise, so this controller is applicable for power factor correction application. In this paper analysis, design and implementation of charge current controlled integrated buck flayback converter is proposed. A universal range of ac input (90-230V), 48V dc output, 100W load, 100 KHz switching frequency integrated converter is implemented using MATLAB/ Simulink software. Experimental results conform and validate the analysis.

A novel single-phase AC–DC bridgeless boost converter for PFC application

ABSTRACTA novel single-phase AC–DC bridgeless boost power factor correction (PFC) converter is proposed in this paper. This converter is constructed by paralleling a boost and a buck–boost topology. It features a solid connection between the input and output ground terminals leading to low common mode noise. Moreover, it possesses a high PFC performance which can satisfy IEC-61000-3-2 Class D Limits completely and only two semiconductors conducting in the current-flowing path. In addition, the two power switches are driven by the same control signal resulting in a simple controller. The detailed circuit operation principle in discontinuous conduction mode is presented. A simulated model established by PSIM software and a lab prototype is designed to validate the effectiveness of this proposed PFC converter.

A modified boost rectifier for elimination of circulating current in power factor correction applications

This paper develops a modified AC/DC boost rectifier for power factor correction applications. The developed rectifier topology uses fewer devices compared to semi-bridgeless type boost rectifiers, and the overall efficiency is increased due to the elimination of the circulating current provided by the inductors. Moreover, it achieves a higher power factor and better total harmonic distortion (THD) in high load conditions. The performance of the developed topology was evaluated and verified by means of simulation and hardware experimental results.

Z-Source Resonant Converter With Power Factor Correction for Wireless Power Transfer Applications

In this paper, the Z-source converter is introduced to power factor correction (PFC) applications. The concept is demonstrated through a wireless power transfer (WPT) system for electric vehicle battery charging, namely Z-source resonant converter (ZSRC). Due to the Z-source network (ZSN), the ZSRC inherently performs PFC and regulate the system output voltage simultaneously, without adding extra semiconductor devices and control circuitry to the conventional WPT system such as conventional PFC converters do. In other words, the ZSN can be categorized as a family of the single-stage PFC converters. In addition, the ZSN is suitable for high-power applications since it is immune to shoot-through states, which increases reliability and adds a boost feature to the system. The ZSRC-based WPT system operating principle is described and analyzed in this paper. Simulations and experimental results based on a 1-kW prototype with 20-cm air gap between the system primary and secondary sides are presented to validate the analysis and demonstrate the effectiveness of the ZSN in the PFC of the WPT system.

Modified Ćuk converter for high‐performance power factor correction applications

This paper presents a modified Ćuk (m-Ćuk) converter to reduce the total harmonic distortion in single-stage power factor correction AC–DC circuits. This modification allows the converter to operate in continuous conduction mode even in the zero-crossing area avoiding distortion in its vicinity. The proposed converter is analysed, designed and implemented. The simulation results and experimental measurements verify the feasibility of the proposed m-Ćuk converter.

Loss-Free Resistor-Based Power Factor Correction Using a Semi-Bridgeless Boost Rectifier in Sliding-Mode Control

In this paper, a loss-free resistor based on a semi-bridgeless rectifier is proposed for power factor correction applications. This particular bridgeless rectifier type is composed of two different boost cells which operate complementarily during each half-line cycle. In case of two unbalanced inductors, many control techniques can produce different inductor current ripples during each half-line cycle that can result in the addition of a dc component to the line current. This paper demonstrates that the application of sliding-mode control by means of hysteretic controllers results in a first-order stable system that can mitigate these harmful consequences due to its capability to ensure the symmetry of the line input current waveform for both positive and negative half-line cycles. Thus, the system does not absorb any dc component from the grid and it is also capable of reducing dramatically the amplitude of the third harmonic. The theoretical predictions have been validated by means of PSIM simulations and experimentally on a prototype of 1 kW which has been controlled using only one sliding control surface.

Comparative study of VIENNA rectifier topologies

VIENNA rectifier is a three-phase three-level boost converter used for active power factor correction (APFC) applications. It utilises an AC switching element in combination with diodes and capacitor to realise it. Three variants of this converter can be arrived at depending on how the AC switching element is realised. This results in variation in efficiency and rating of the components used for a specified power, input voltage, and switching frequency. In this paper all the three variants are simulated, compared, and benchmarked for a 10 kW converter operating on a line voltage of 400 V AC. Design calculations for all the three topologies are provided. Current and voltage rating of various components are calculated. Power dissipated by each and every component is calculated and efficiency between the topologies is compared at switching frequency (fS) of 50 kHz. The efficiency at different switching frequencies for each topology is calculated and plotted.

High Switches Utilization Single-Phase PWM Boost-Type PFC Rectifier Topologies Multiplying the Switching Frequency

Decades of research have seen single-phase boost-type pulse-width modulation converters be employed as front-end power factor correction (PFC) rectifiers in commercial power supplies. The benefits of employing this technology to comply with power quality standards while assuring high efficiency, low volume, and weight have been observed. However, this paper shows that further efforts can be driven toward new topologies. In this context, novel single-phase rectifier circuits are introduced. These are able to double or triple the ripple frequency present at the input components. Furthermore, a high utilization of the switches is observed during both positive and negative grid half-cycles. The theoretical analysis of the proposed topologies as well as their operation in PFC applications are presented and different operation modes are proposed and a comparison with a state-of-the-art PFC rectifier is presented. Finally, experimental verification of a PFC rectifier doubling the switching frequency is presented in a 1-kW prototype employing a current self-control strategy.