AC-DC Power Factor Correction Converter Research Articles

Design and Control of Two Stage Battery Charger for Low Voltage Electric Vehicles Using High Gain Buck-Boost PFC AC-DC Converter

The design and control of a two-stage onboard battery charger (OBC) for the low-voltage electric vehicle (LVEVs) are presented in this study. The presented charger operates over a wide range of AC input voltage at high power factor. The presented charger utilizes a bridgeless high gain high power factor AC-DC converter with continuous input current characteristics at its front end. At the back end of the charger, an isolated Cuk DC-DC converter is employed to control and implement different battery charging modes, viz. constant current (CC) and constant voltage (CV) charging profiles. The presented AC-DC converter operates under discontinuous current mode (DCM) operation and achieves minimum control complexity at the AC-DC stage. The DCM design and high voltage conversion ratio allow it to function reliably over a comprehensive range of input and intermediate DC link voltage. This study covers the charger's design for a power rating of 650 W and output battery voltage of 24 to 72 V. The overall operational analysis and effectiveness of the design are verified through both simulations and experimental implementation and the performance is compared with other contemporary power factor correction (PFC) topologies on various parameters.

A single-phase level-shifted duty controlled multilevel rectifier-based EV charger for wide output voltage range

Nowadays, electric vehicles (EVs) are gaining popularity with customers and as an environmentally-friendly option owing to the rise in petroleum prices and pollution, respectively. The battery is the prime source of power for EVs. This paper presents, a level-shifted duty controlled multilevel power factor correction (PFC) AC-DC converter, followed by a phase-shifted full-bridge converter (PSFBC) as an efficient charging solution for EVs. The adopted topology uses fewer semiconductor switching devices than traditional multilevel converters, which minimises switching losses, making it a good choice for a compact EV charger. Complete system design is carried out for a single-phase, 3.3 kW, EV charger, with 220 vrms AC input and 48-72 V DC output voltage for batteries. This EV charger has improved the system reliability and efficiency, along with the near-unity power factor (UPF) in compliance with the international IEC-61000-3-2 PQ standard. MATLAB/Simulink and experimental results are presented to validate the aforementioned functionalities of this EV charger.

A Soft-Switched Power-Factor-Corrected Single-Phase Bidirectional AC–DC Wireless Power Transfer Converter With an Integrated Power Stage

Bidirectional ac–dc wireless power transfer (WPT) converters are widely used in grid-connected electric vehicle systems for grid-to-vehicle and vehicle-to-grid applications. They usually apply a two-stage topology with a bidirectional ac–dc power factor correction converter and a bidirectional dc–dc WPT converter. Such a two-stage topology cannot achieve high efficiency and low cost. Recently, single-stage matrix bidirectional ac–dc WPT converters have been proposed. However, the matrix-converter-based topologies do not utilize remarkably lower count of power switches and generate large double-line frequency ripple in the dc-side voltage or current. This article proposes a new single-phase bidirectional ac–dc WPT topology with an integrated power stage to overcome the drawbacks of the matrix-converter-based topologies and retain the advantages of single-stage topologies. Description of the proposed topology with the modulation and control methods, theoretical analysis, and reference design procedure are presented in detail. Finally, a scaled-down laboratory prototype with 500-W output power is implemented with experimental results presented to validate the principle, analysis, and design.

Analysis of a new SEPIC AC–DC PFC converter for light emitting diode applications

Active power factor correction (PFC) converters are used to increase the power factor and improve the total harmonic distortion as a result of reducing the harmonics in the current. In this paper, a new bridgeless single-ended primary inductor converter (SEPIC) topology used in light emitting diode (LED) load is proposed to obtain near-unity power factor. By eliminating the input bridge in the bridge PFC converter, the total harmonics distortion is improved and a lower cost is obtained. The reactive power control is used to generate the reference current signal in the proposed converter to control the LED current. To demonstrate the applicability of the proposed topology and to compare its performance with the bridge SEPIC topology, PSIM circuit simulation was used, and an experimental prototype was performed. In the experimental study, 25 Vrms input voltage was applied, and 10 V DC voltage was obtained at the output. Using the proposed converter, the total harmonic distortion value was reduced from 5.722% to 1.837%, and the power factor was increased to 0.999. The experimental and simulation results showed that the total harmonic distortion value of the input current improved and that the proposed SEPIC PFC converter for low-power circuits, particularly in LED applications, is a very good option.

A Review of Three Phase AC-DC Power Factor Correction Converters for Electric Vehicle Fast Charging

Electric vehicle charging station for fast DC charging performs AC-DC conversion at off-board. In recent years, three-phase AC-DC power factor correction (PFC) converters are dealt with fast charger. These converters are developed using unidirectional and bidirectional power flow structure. In this study, three-phase AC-DC PFC converter topologies, providing bidirectional power flow, are evaluated in terms of performance. The aim is to present the latest technology of bidirectional multilevel AC-DC PFC converters for EV fast charging. This paper provides a comprehensive and practical review for researchers interested in fast charging infrastructure for electric vehicles.

Stability Analysis of Two-Stage Single-Phase Converter System Adopting Electrolytic Capacitor-Less Second Harmonic Current Compensator

For the two-stage single-phase converter, including the power factor correction (PFC) ac-dc converter and dc-ac inverter, a second harmonic current compensator (SHCC) can be introduced to handle the second harmonic current (SHC) for removing the undesired electrolytic capacitor. Consequently, the two-stage single-phase converter becomes a multi-converter system. In this paper, the ac-dc stage or dc-ac stage in the system is categorized into two types in terms of the control objectives, i.e., the bus-voltage-controlled converter (BVCC) and the bus-current controlled converter (BCCC). The SHCC is a BCCC since its bus-port current is directly controlled, and the bus-port impedance of the SHCC is derived, which is affected by the ac-dc stage or dc-ac stage since the SHC reference is extracted from them. The system stability is investigated with the impedance-based stability criterion, and it is found that the system stability is different when the ac-dc stage or dc-ac stage is operated as a BVCC or a BCCC. Specifically, only when the ac-dc stage is operated as a BVCC, the system is unstable; while for other cases, the system is certainly stable. For the applications where the ac-dc stage is operated as a BVCC, a virtual resistor is introduced and realized by the control scheme of the SHCC to ensure the system stability. Finally, a two-stage single-phase PFC ac-dc converter is fabricated and tested to verify the theoretical analysis.

HIGH EFFICIENCY BRIDGELESS SINGLE POWER CONVERSION BATTERY CHARGER WITH TRANSFORMATIVE INTRINSIC ALGORITHM FOR LIGHT ELECTRIC VEHICLES

Bridge single-power conversion AC-DC converter for high conversion efficiency. Power factor correction (PFC) AC-DC converters are widely used in grid-connected power systems, such as suppliers of shared DC buses in buildings / mobile charging stations and electric vehicle chargers. These PFC AC-DC converters must meet high-harmonic-regulated bridge single-supply conversion AC-DC converters to achieve high conversion efficiency. The project's simulation modeling and hybrid AC / DC micro grid control. The performance of a single power conversion AC / DC micro grid system is analyzed in a grid-hook or autonomous mode. DC-AC / DC converter is a high-frequency power conversion circuit that uses high-frequency switches and inductors, transformers, and capacitors to smooth the noise and switch to a regulated DC voltage. The proposed system transformation inherent algorithm for changing the input voltage and output current is effectively controlling the differential load even when maintaining a constant voltage output. The controller will access both the steady-state and transient conditions of the power management and control scheme on the load side.

An Improved Single Stage Phase Shifted Control Based AC–DC PFC Converter for Wireless Applications

Recently, many researchers has more attention in a single stage AC to DC converter features and DC to DC regulator are extensively used into low power applications. When compared with the two stage conventional method over the Single stage converter has a simple design and utilize only less components. Therefore, this task has been used in this paper as a prposed work of AC–DC single stage converters combine a converter front end with DC–DC back end converter. This proposed work has been improved single stage power factor correction (PFC) converter based on phase-shifted controller for wireless Power applications. The proposed technique employed to develop the improved converter for task of an extensive series of voltage outputs with rippleless outcomes in low frequency, that shows the high essential in battery application and the PFC duty ratio restriction is eradicated. Similarly, DC–DC stage operation are designed in a related way of conventional full bridge phase shifted converter. Accordingly, the proposed technique of improved converter of this paper will achieves better efficiency compared with other conventional techniques and it has been prove more efficient for many Industrial applications, it has been discussed in result section clearly. The experimental results of proposed improved converter proves that it is potential to extend high power single stage converter with good power factor, conversion characteristics and efficiency.

Design and development of single phase AC–DC discontinuous conduction mode modified bridgeless positive output Luo converter for power quality improvement

Power factor corrected AC–DC converter topologies have been of research interest for DC power supplies. The main goal of this work is to improve power quality at the supply side and maintain constant DC voltage at the output side by designing a Modified Bridge Less Positive Output Luo (MBLPOL) power factor correction (PFC) converter. Discontinuous conduction mode is also possible for input PFC with a small filter at the source side. In order to regulate the DC load voltage for various loads and supply voltage conditions, a feedback control circuit with a single voltage sensor is proposed for the PFC converter. A prototype of 100 W, 48 V, AC–DC MBLPOL converter is designed and tested. Proper design of controller for the converter guarantees the excellent performance and the same is validated with the help of simulation and hardware results. The proposed MBLPOL converter is tested for DC load voltage regulation for various load power and supply voltage variations. The experimental study shows supply current total harmonic distortion of 1.24% at rated load while maintaining unity power factor.

Investigation and Modeling of Combined Feedforward and Feedback Control Schemes to Improve the Performance of Differential Mode Active EMI Filters in AC–DC Power Converters

In this paper, the models of active differential mode electromagnetic interference input filters for ac–dc converters are first investigated. The models are developed for active filters with single feedback (FB) and single feedforward (FF) configurations, which include an active filter, passive filters, and the noise model for a converter. To increase the gain of the single active filter, the models for FB–FF, FF–FB, parallel FB, and series feedback (SFB) configurations are developed and investigated. Loop gains and insertion gains for all of these configurations are derived and compared. Stability has been analyzed based on the loop gains and a compensation technique is introduced to ensure stability. Based on the comparison among all these control configurations, it has been found that the SFB configuration can achieve the highest noise reduction. The loop gains and insertion gains of an active filter prototype with the SFB configuration are measured using a network analyzer to validate the developed model and compensation technique. Finally, spectrum measurements with a commercial boost power factor correction ac–dc converter have been conducted to verify the developed modeling and control techniques as well as the predicted performance for the SFB configuration.

One-Cycle Control for Electrolytic Capacitor-Less Second Harmonic Current Compensator

The input power of the single-phase power factor correction ac–dc converter pulsates at twice the line frequency, while the output power of the single-phase dc–ac inverter pulsates at twice the output frequency. The pulsating power will result in second harmonic current (SHC) in the ac–dc converter and dc–ac inverter. In this paper, electrolytic capacitor-less second harmonic current compensator (SHCC) is presented to compensate the SHC. The SHCC has two operating modes, namely, charging mode and discharging mode. To achieve an excellent SHC compensation performance, a hybrid one-cycle control (OCC) is proposed to regulate the port current of the SHCC, and the SHCC can stably operate in both the charging mode and discharging mode. To avoid the mode detection required in the hybrid OCC and ensure seamless transition between the two modes, the OCC with dc bias is further proposed. Besides, a peak voltage control is proposed to regulate the storage capacitor voltage in the SHCC for reducing the power losses of the SHCC at light load. A 1-kW two-stage inverter with the SHCC is fabricated and tested, and the experimental results are provided to verify the effectiveness of the proposed control schemes.

Control method for improving the response of single‐phase continuous conduction mode boost power factor correction converter

Continuous conduction mode power factor correction AC–DC converters are widely employed as the front stage in power supplies with medium or high output power. The second-order reactive input power in single-phase systems causes second-order ripple in the DC-link voltage. The speed of voltage regulation is thus limited by the second-order frequency in seeking to achieve low distorted input current. This study presents a fast second-order voltage estimation method, wherein an integrator is used for the estimation of second-order voltage ripple to obtain rapid voltage feedback without ripple and thereby cope with the limitations imposed by the second-order frequency. This approach greatly expands the bandwidth of the voltage control loop beyond the second-order frequency while reducing the total harmonic distortion associated with the input current. This also makes it possible to reduce the DC capacitance to reduce costs. The authors opted for full digital control using a TI F28335 DSP IC, in conjunction with feedback plus feedforward control to facilitate the design of the current loop. A feedback current corrector is used to reduce distortion associated with the input current over a wide load range. The effectiveness of the proposed control method was confirmed with some simulation and experimental results.

Performance Analysis of various Power Converters for Power Factor Correction in BLDC Motor with Fuzzy Logic Controller

Enhance the efficiency of the motor drive by Power Factor Correction (PFC) play a critical part in the energy saving during energy consumption. Permanent magnet brushless DC Motor (PMBLDCM) drives are being utilized in numerous variable speed applications because of their high productivity, quiet operation, high reliability, simplicity of control, and low maintenance requirement. These drives have power quality issues and poor power factor at input AC mains as they are mostly fed through diode bridge rectifier. To overcome such issues a single stage single-switch power factor correction AC-DC converter topology are utilized. This paper gives the relative evaluation of the different converter with Proportional Integral Controller (PIC) And Fuzzy Logic Controller (FLC). In this system, the speed of the motor is shifted by the Impedance Source Inverter (ZSI) dc voltage. The proposed drive is realized to achieve a unity power factor at ac mains for a broad scope of speed control and supply voltage flucation. A MATLAB/Simulink environment is used to reproduce the model to fulfill an extensive variety of speed control with improved Power Quality (PQ) at the supply.

Analysis and Design of a PFC AC-DC Converter with Electrical Isolation

This study presents a single-phase power factor correction AC–DC converter that operates in discontinuous conduction mode. This converter uses the pulse-width modulation technique to achieve almost unity power factor and low total harmonic distortion of input current for universal input voltage (90 Vrms to 264 Vrms) applications. The converter has a simple structure and electrical isolation. The magnetizing-inductor energy of the transformer can be recycled to the output without an additional third winding. The steady-state analysis of voltage gain and boundary operating conditions are discussed in detail. Finally, experimental results are shown to verify the performance of the proposed converter.

Analysis and Design of a New AC–DC Single-Stage Full-Bridge PWM Converter With Two Controllers

Single-phase power factor correction (PFC) ac-dc converters are widely used in the industry for ac-dc power conversion from single phase ac-mains to an isolated output dc voltage. Typically, for high-power applications, such converters use an ac-dc boost input converter followed by a dc-dc full-bridge converter. A new ac-dc single-stage high-power universal PFC ac input full-bridge, pulse-width modulated converter is proposed in this paper. The converter can operate with an excellent input power factor, continuous input and output currents, and a non-excessive intermediate dc bus voltage and has reduced number of semiconductor devices thus presenting a cost-effective novel solution for such applications. In this paper, the operation of the proposed converter is explained, a steady-state analysis of its operation is performed, and the results of the analysis are used to develop a procedure for its design. The operation of the proposed converter is confirmed with results obtained from an experimental prototype.

Suppression of Line Frequency Instabilities in PFC AC-DC Power Supplies by Feedback Notch Filtering the Pre-Regulator Output Voltage

Due to nonlinear effects, Power Factor Correction (PFC) ac-dc converters working in Continuous Conduction Mode (CCM) can exhibit nonlinear phenomena such as subharmonic oscillations and chaotic regimes at the line frequency. These undesirable behaviors increase the Total Harmonic Distortion (THD) and shift the dc input line current to non null values. This results in a malfunctioning of the system or even damages caused by the increase of the temperature which can jeopardize enormously the performances and shorten the lifetime of the system. In order to avoid these problems, subharmonic line frequency instabilities must be suppressed. In this paper, a selective notch filter based controller is combined with the output voltage compensator to suppress these instabilities and to stabilize a two-stage PFC ac-dc converter. A frequency domain analysis is used to explain the control mechanism of directing subharmonic and chaotic oscillations into stable periodic motion. A detailed study of the effect of this selective filter on the dynamical behavior of the system is presented. A simple harmonic model is used to obtain the control stability domain. This control technique is simple and allows widening the stability domain and improving the performances of the system being its experimental implementation possible using standard devices such as OAs and passive elements. The correctness of the proposed technique is verified with numerical simulations and experimental measurements.

Increase of Efficiency of an AC-DC Power Factor Correction Boost Converter by a Novel Soft-switching Technique

A novel implementation of a high power factor boost converter with increased efficiency is described. In this converter, a new zero-voltage transition technique is used for soft switching of the main and auxiliary switches; also, no additional voltage and current stresses on the main and auxiliary switches occur. The operating modes, theoretical analysis, and design considerations of the proposed converter are explained in detail. To evaluate the performance of the proposed converter, simulation and experimental results for a 400-V, 50-kHz, 0.5-kW prototype AC-DC power factor correction converter is presented. Finally the simulation and experimental results are given to verify its rationality and practicability.

Fuzzy Controlled Parallel AC-DC Converter for PFC

Paralleling of converter modules is a well-known technique that is often used in medium-power applications to achieve the desired output power by using smaller size of high frequency transformers and inductors. In this paper, a parallel-connected single-phase PFC topology using flyback and forward converters is proposed to improve the output voltage regulation with simultaneous input power factor correction (PFC) and control. The goal of the control is to stabilize the output voltage of the converter against the load variations. The paper presents the derivation of fuzzy control rules for the dc/dc converter circuit and control algorithm for regulating the dc/dc converter. This paper presents a design example and circuit analysis for 200 W power supply. The proposed approach offers cost effective, compact and efficient AC/DC converter by the use of parallel power processing. MATLAB/SIMULINK is used for implementation and simulation results show the performance improvement.

A REPRESENTATIVE DISCRETE-TIME MODEL FOR UNCOVERING SLOW AND FAST SCALE INSTABILITIES IN BOOST POWER FACTOR CORRECTION AC-DC PRE-REGULATORS

Boost Power Factor Correction (PFC) AC-DC converter under fixed frequency average current control is a nonlinear and nonautonomous dynamical system characterized by two different forcing periods and thus by two different scales of time. Four different kinds of standard instability phenomena are possible for this system, depending on the parameters of the circuit. A combination of more than one instability phenomenon can also take place. In this paper, we carry out a careful and an accurate modeling of the system. First, we put into evidence most of the nonlinear behaviors that could occur in the system by using the switched circuit-based model and then we derive a unified representative discrete-time model that is able to predict accurately all these behaviors.

A Variable Frequency Phase-Shift Modulated Three-Level Resonant Single-Stage Power Factor Correction Converter

This paper presents a new single-stage three-level resonant power factor correction ac-dc converter suitable for high power applications (in the order of multiple kilowatts) with a universal input voltage range (90-265 Vrms). The proposed topology integrates the boost input power factor preregulator with a half-bridge three-level resonant dc-dc converter. The converter operation is controlled by means of a combination of phase-shift and variable frequency control. The phase-shift between the switch gate pulses is used to provide the required input current shaping and to regulate the dc-bus voltage to a set reference value for all loading conditions, whereas, variable frequency control is used to tightly regulate the output voltage. An auxiliary circuit is used in order to balance the voltage across the two dc-bus capacitors. Zero voltage switching (ZVS) is also achieved for a wide range of loading and input voltage by having a lagging resonant current in addition to the flowing of the boost inductor current through the body diodes of the upper pair of switches in the free wheeling mode. The resulting circuit, therefore, has high conversion efficiency and lower component stresses making it suitable for high power, wide input voltage range applications. The effectiveness of the proposed converter is verified by analysis, simulation, and experimental results.