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In this paper, a DC power supply is presented that, in addition to a power factor correction, is equipped with an active power filter function. This function enables compensation of both the reactive and the distortion power, generated by an external load, which is connected to the same power line node as the presented device. A tuneable inductive filter is added at the input of the power electronics controlled current source, which constitutes the main block of the power supply. This filter allows for a visible improvement in the quality of the current source control, compared to a similar device with a fixed inductive filter. This improvement depends on extending the "frequency response" of the current source, which facilitates an increase in the dynamics of changes in the input current of the power supply. The actual modification to the presented device is related to its control section, which is equipped with analogue regulators. The main purpose of this work is to present the results from a simulation model of an electrical system with a power supply, especially compared to those from a similar device but with a discrete control. The work represents a continuation of a research cycle on DC power supplies that are equipped with a power compensation function and are based on tuneable magnetic devices. [ABSTRACT FROM AUTHOR]

This paper introduces a current regulator for a three-phase Neutral-Point Clamped rectifier. The current regulator maintains power quality parameters at both sides of the rectifier for any perturbed conditions. The controller adapts itself according to any change in load or supply voltage. The current controller senses the DC-bus potential difference and modifies the input controlling signals to generate desired gate pulses for driving the converter efficiently. Simulation results exhibit the effectiveness of the newly proposed control technique under various operating conditions. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Boost converter topology is most widely used for power factor correction (PFC) converters. The conventional passive Boost PFC converter inherently suffers from the lack of controllability and non-ideal characteristics of the diode-bridge rectifier. Replacing diodes with active switch(es) offers viable solutions but increases the circuit complexity. Addressing this trade-off, a novel design of a single–phase input switched AC to DC Boost converter has been presented in this article. The active switch of the Boost DC converter is shifted to the input side of the full-bridge diode rectifier which provides more control on the input current without increasing much of the circuit complexity. Two Boost inductors and two output split capacitors are used for providing higher step-up operation compared to the conventional. The converter has been simulated both in open-loop and closed-loop conditions using the PSIM software. The simulation results show that the proposed converter provides good dynamic response and can maintain a constant stable output voltage during sudden load change. Furthermore, to evaluate the experimental performance of the suggested converter, a prototype converter has been developed. A scaled-down experiment has been performed which shows that the converter can achieve up to 85.2 % efficiency and an input power factor of 0.9.

This paper presents the power factor corrected Y-Cell Modified Boost (YCMB) converter-fed battery charger for electric vehicle (EV) applications. The proposed YCMB converter-based EV charging system eliminates all the nonlinearities of the conventional AC-DC charging system, therefore, the total harmonic distortion (THD) in current at the source side becomes less than 5 % during both the charging modes throughout the charging operation (from deep discharge to fully charged) of the battery in constant current and constant voltage mode of operations. Therefore, the system is meeting international standards of power quality including IEEE519 and IEC61000-3-2. Whereas, the conventional battery charging systems draw a non-sinusoidal source current of very high THD. The presented scheme has converted a highly nonlinear conventional AC-DC EV charging system into a linear system that suppresses all the harmonic currents and reduces reactive power demanded by the system from the source using YCMB converter topology and effective control technique. It also eliminates the requirement of input LC filter for harmonic reduction at source side current which in turn reduces the size and significantly enhances the system efficiency (up to 95 %). The control section of the presented scheme consists of two major loops. The sliding mode feature in the power factor correction control loop of the system removes all the possibilities of a sudden spike in source current under all dynamic operating conditions thus ensuring the PFC operation at dynamic operating conditions unlike the conventional systems. The simulation model and laboratory prototype of the presented scheme has been developed. The simulated and experimental performance of the system is found to be significantly improved and satisfactory under steady state and various dynamic operating conditions.

This paper presents the implementation for the first time of a Multi-Particle Swarm Optimization (MPSO) algorithm in the tuning of a PID controller for Power Factor Correction (PFC), applied to a 100W AC-DC boost converter. MPSO algorithm navigates in a search space where each dimension of the space corresponds to the controller constants (Proportional, Integral, Derivative and the Derivative Filter), prioritizing communication over exploration in the algorithm. The controller parameters are randomly initialized in a reduced sector of the space [[Formula: see text],[Formula: see text],[Formula: see text],[Formula: see text]], to optimize the search for a PID solution. In the first step, the algorithm is validated using a simulation model in Simulink and Matlab. Subsequently, a final implementation using a real converter is implemented with the PID tuned by MPSO, improving the PFC obtained in previous work. Although previous works have used evolutionary algorithms applied to heuristic optimization to tunning PID controllers, the MPSO algorithm is not usually used for this purpose, particularly to tunning a PID controller in a power electronics system. One advantage of MPSO over the PSO classical algorithm is the search at different points if the vectorial field looks for an optimal solution. PSO presents problems such as getting stuck in a locally optimal solution. The PID controller is trained offline, with the advantage of allowing the risk of damage in the Boost converter for transitory response, increasing the performance of the Power Factor Correction in the converter. This research opens the possibility to use the extended version of the PSO bioinspired algorithm to tune offline controllers to improve the power converter's performance, minimizing the risk presented in the real-time tuning process.

Research and development of power factor corrector (PFC) for AC/DC converters of single-phase AC power supply network are discussed within this article. Two-channel bridgeless PFC is proposed in this paper. The proposed converter allows us to lower current DC component generation in the power network and to reduce static and dynamic losses of semiconductor devices. The suggested solution characteristic features are the absence of a diode bridge while using two identical converters operating in different power network voltage half periods. Due to cumulative chokes in each converter, the function setting the consumption current sinusoidal form is realized with the ability of wide-range output voltage regulation. A number of Simulink-models have been developed in order to study operating modes and to test control algorithms of the proposed bridgeless PFC. The input current harmonic content, efficiency coefficient, passive elements’ electrical parameters, and output voltage pulsation coefficient of the proposed bridgeless PFC were researched by Simulink-models. The results obtained show the efficiency of the proposed solutions regarding PFC. The THD value does not exceed 1.3% in steady state mode and is not over 4% during the voltage stabilization process; the minimal value of the output voltage pulsation coefficient is 3.1%. The suggested solutions can be applied in accumulator batteries’ charging sets and DC motors’ reduced-current start.

To solve the problem of the large size of traditional industrial frequency phase-shift transformers and the harmonic distortion of multi-pulse wave rectifier systems, this paper proposes a three-stage shunt zigzag power electronic phase-shift transformer based on a double-tap multi-pulse wave rectifier, which combines the power factor correction (PFC) converter with the voltage-type SPWM inverter circuit to form a power electronic converter to realize the frequency boost and power factor correction. Through AC–DC–AC conversion, the frequency of the three-phase AC input voltage is increased, the number of core and coil turns in the transformer is reduced to reduce the size of the phase-shifter transformer, a zigzag structure of the phase-shifter transformer is used to solve the unbalanced distribution of current between the diode bridges, and a passive harmonic suppression method on the DC side is used to generate a loop current by using a group of single-phase rectifier bridges to regulate the input line current of the phase-shifter transformer. The phase-shifted voltage is input into two three-phase diode rectifier bridges to rectify and supply power to the load. Simulation and semi-physical test results show that the proposed method reduces the total harmonic distortion (THD) value of the input current of the phase-shifted transformer to 7.17%, and the THD value of the grid-side input current is further reduced to 2.49%, which meets the harmonic standard and realizes the purpose of power factor correction as well as being more suitable for high-power applications.

The widespread use of static converters for controlling electrical machines and the concern for electrical power quality in industrial environments provide an opportunity for utilizing these devices to enhance the power quality. In this context, this work presents a back-to-back converter model for driving induction machines. The converter is designed to correct the power factor of the point common coupling (PCC), compensate for harmonic currents (acting as an active filter), and withstand voltage sags. The necessary control system models were developed, and an alternative implementation for these functions in the converter was proposed. The results demonstrate the technical feasibility of this solution, as the converter operated within its nominal limits by compensating for harmonics and reactive power. Moreover, the equipment showed resilience to severe voltage sags. The contribution of this paper focuses on the multifunctionality of the frequency converter for driving induction machines. It emphasizes the advantage of the inverter in improving power quality in industrial environments through reactive power compensation and harmonic current compensation, thus functioning as an active power filter. Additionally, it is worth highlighting its ability to handle voltage dips. In this regard, this paper contributes by providing an operational strategy for driving the induction machine during such transients.

This paper expands a recently proposed peak current-mode (PCM) control method for a power factor correction (PFC) boost converter to include the totem-pole converter and solves the controller’s compatibility problem with the totem-pole converter by proposing three input current sensing methods. Using MATLAB/Simulink 2023b, simulation experiments on a 2 kW totem-pole converter utilizing the PFC PCM controller were carried out to assess the performance of the controller with the proposed sensing methods. The findings indicate that under steady-state conditions, all three proposed sensing methods performed input current shaping successfully and yielded nearly identical THD% of about 4.4% in the input current waveform. However, it is noteworthy that method 2, referred to as the memory method, exhibited a sluggish and less robust transient response in comparison to the swift and resilient responses observed with method 1 and method 3. Additionally, the third proposed method, which involves a single current sensor positioned across the input inductor, emerged as the optimal and cost-effective sensing solution. This method achieved the same desirable attributes of fast and robust control while utilizing only a single current sensor, a notable advantage over method 1, which employs two current sensors.

In various industrial applications, the use of a power supply that uses a conventional diode single-phase rectifier topology results in high harmonic values in the electricity distribution system. One of the real impacts of this harmonic value is the heating of the electric power system equipment and power losses. High rms current values due to harmonics often cause problems in protection settings in addition to efficiency problems. The percentage value between the total harmonic component and the fundamental component is called THD (Total Harmonic Distortions). Therefore, in this study an asynchronous dc/dc boost converter is connected to the output side of a single-phase diode rectifier which is capable of improving power factor and low harmonics. So that a THD value of less than 15%, PF (Power Factor) = 0.92-1 and a sinusoidal input current can be obtained. The implementation results show that the PFC (Power Factor Correction) method can work well on single-phase diode rectifiers.

Abstract This paper investigates the design and implementation of a new single‐phase sensorless power factor corrected (PFC) circuit. Here, the inductor‐current sensor and its sensing circuit are removed. As a result, the cost and volume of the PFC circuit are effectively reduced. Two different methods, including an inductor‐voltage estimation method and an inductor‐current estimation method, are proposed and compared. To improve the dynamic responses of the PFC circuit, predictive voltage control and predictive current control are implemented here. A digital signal processor, type TMS‐320F‐2808, manufactured by Texas Instruments, is used here as the control centre to execute the sensorless methods and control algorithms. A 400 W, 50 kHz switching frequency, single‐phase alternating current (AC) 110 V /DC 300 V PFC circuit is implemented. The measured results validate the feasibility and correctness of the proposed methods. This proposed sensorless PFC circuit can be widely applied in industry due to its simplicity.

Abstract In low‐voltage distribution systems, the increased penetration of power electronic devices leads to the decentralization of harmonic sources, which puts the sensitive loads or communication systems in the risk status. The conventional methods of point‐to‐point harmonic control are not applicable. In order to solve this problem without increasing additional investments, this paper focuses on mitigating the harmonic interference through the power factor correction (PFC) converter. Hence, a critical conduction mode (CRM) single‐phase boost PFC converter with adaptive harmonic compensation (AHC) control is proposed to reduce the harmonic interference at user side. Firstly, the feed‐forward control loop of a PFC converter is decoupled into the fundamental branch and harmonic branch to trace the harmonic interference and generate the compensation current. Then the compensation gain is designed by the compensation loop gain and compensation capacity of PFC converter. Meanwhile, the characteristics of the PFC converter are analyzed to study the effect of the AHC control on the active power transmission and output load, which can provide important support for the proposed method in application. Finally, a 160‐W experimental prototype is built to verify the effectiveness of the proposed AHC control.

Abstract This paper studies the effect of the number of switching (NOS) per day of capacitor banks on loss reduction in radial distribution systems. To this aim, the daytime (more precisely, 24 h) is divided into different numbers of time segments (equal to the same NOS) for capacitors’ size switching. The resulting non‐linear programming with discontinuous derivatives (called DNLP) model is solved subject to related constraints. The results reveal the impact of hourly switching of capacitor banks on further loss reduction (namely 118.4435, 83.7856, and 101.738 MWh for three IEEE systems) and higher net savings (i.e. k$5.6067, k$4.2772, and k$5.3542 for the same systems) of radial distribution systems compared to daily switching. Then, the hyper‐tuned Random Forest model is trained based on the IEEE 69‐bus network, fine‐tuned by the IEEE 10‐bus network, and fitted by the IEEE 33‐bus network to have an intelligent multi‐classification task with the highest accuracy. Numerical simulation, in both classic and intelligent parts, is presented to demonstrate the performance of DeepOptaCap. For the final step, DeepOptaCast is compared to other intelligent models of Light Gradient Boosting Method (LGBM), Decision Tree, and XGBoost, regarding KPIs of mean absolute percentage error, root mean squared percentage error, mean absolute error, root mean squared error, and coefficient of determination to demonstrate the model's superiority.

This paper presents a novel reference current calculation method for harmonics mitigation and reactive power compensation in power systems. This method was applied to a unique hybrid power filter topology. The motivation for this study comes from the increasing power quality issues, such as harmonic distortion and resonances, caused by the widespread integration of converter-interfaced generation (CIG) and modern nonlinear loads into the power system in recent years. The goal of this study is to propose a cost-effective and practical solution for current harmonics filtering and power factor correction by combining the advantages of passive and active filters into a hybrid solution. The developed reference current calculation method, which is based on customer current harmonic emissions, enables effective reference current calculation. Theoretical analyses along with simulation results obtained from a medium-voltage benchmark model in PSCAD verify the effectiveness of the proposed solution in harmonics filtering and show a substantial reduction in filter current ratings across various harmonic components. In addition, the simulation results were evaluated by comparison with the results obtained from a real-time simulator. [ABSTRACT FROM AUTHOR]

This paper proposes an interleaved multilevel converter (MLC)-based charger with power rating 2.8 kW to charge on-board battery of electric vehicle (EV). It comprises two stages: (1) an interleaved multilevel ac–dc converter; and (2) an LLC-resonant dc–dc converter. The interleaved approach efficiently maintains the optimum power level. The switching scheme implemented for MLC maintains the source current sinusoidal, supports unity power factor (UPF) and has the capability to balance the capacitor voltage. The MLC maintains UPF and balances capacitor voltage without any auxiliary circuit. In addition, MLC provides lower voltage stress and reduced total harmonic distortion (THD), therefore, making it a better choice for ac–dc conversion stage in battery charging application. The dc–dc converter furnishes regulated and wide output voltage range for on-board charging system. The principle of operation, modulation technique and control strategy for both the converters are analysed. Following theoretical analysis, laboratory experiments were conducted to validate the implemented approach. The results signify that for output voltage range of 24−72 V, UPF is maintained at input, lower stress across switches and capacitor voltage is balanced. The performance of MLC is satisfactory as it attains a peak efficiency of 97% with THD of 2.07%. [ABSTRACT FROM AUTHOR]

This paper presents the implementation for the first time of a Multi-Particle Swarm Optimization (MPSO) algorithm in the tuning of a PID controller for Power Factor Correction (PFC), applied to a 100W AC-DC boost converter. MPSO algorithm navigates in a search space where each dimension of the space corresponds to the controller constants (Proportional, Integral, Derivative and the Derivative Filter), prioritizing communication over exploration in the algorithm. The controller parameters are randomly initialized in a reduced sector of the space [ K p , K i , K d , K n ], to optimize the search for a PID solution. In the first step, the algorithm is validated using a simulation model in Simulink and Matlab. Subsequently, a final implementation using a real converter is implemented with the PID tuned by MPSO, improving the PFC obtained in previous work. Although previous works have used evolutionary algorithms applied to heuristic optimization to tunning PID controllers, the MPSO algorithm is not usually used for this purpose, particularly to tunning a PID controller in a power electronics system. One advantage of MPSO over the PSO classical algorithm is the search at different points if the vectorial field looks for an optimal solution. PSO presents problems such as getting stuck in a locally optimal solution. The PID controller is trained offline, with the advantage of allowing the risk of damage in the Boost converter for transitory response, increasing the performance of the Power Factor Correction in the converter. This research opens the possibility to use the extended version of the PSO bioinspired algorithm to tune offline controllers to improve the power converter's performance, minimizing the risk presented in the real-time tuning process. [ABSTRACT FROM AUTHOR]

The traditional light source of projection lamps adopts a halogen lamp, which has the advantages of high brightness, but its luminous efficiency is not good and consumes energy. A light-emitting diode (LED) has the characteristics of high luminous efficiency and energy savings and can be used as a new light source for projection lamps. The conventional two-stage electronic lighting driver circuit for supplying an LED projection lamp is composed of an AC-DC converter with power factor correction (PFC) as the first stage and a DC-DC converter for providing rated lamp voltage and current as the second stage. The conventional LED projection lamp driver circuit has more circuit components, a higher cost and limited efficiency. Therefore, this paper proposes a novel electronic lighting driver circuit for supplying an LED projection lamp with PFC function, which integrates a modified stacked dual boost converter and a half-bridge LLC resonant converter into a single-stage power-conversion circuit. The inductor inside the modified stacked boost converter is designed to operate at discontinuous conduction mode (DCM) for the driver circuit achieving PFC. Wide bandgap semiconductor devices silicon carbide (SiC)-based Schottky diodes are utilized to reduce power diode losses, and soft switching is implemented in the proposed LED projector lamp driver circuit to reduce the switching losses of the power switches and thus improve circuit efficiency. This paper has completed a single-stage prototype driver circuit for an LED projection lamp with PFC function, and the prototype circuit has a high power factor (PF > 0.98), low input current total-harmonic-distortion (THD < 6%) and high efficiency (>89%) in the case of an AC input power supply with an RMS value of 110 volts, and both power switches have the characteristics of soft switching. [ABSTRACT FROM AUTHOR]

Summary: This 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. [ABSTRACT FROM AUTHOR]

Power factor correction (PFC) converters have been frequently employed in various switching power supply devices to reduce input current harmonics. However, the PFC converter suffers from an obvious twice-line-frequency output voltage ripple due to the instantaneous power imbalance between constant output power and variable input power. Suppression of twice-line-frequency ripple usually can be realized by the post-stage DC-DC converter of the two-stage cascade PFC converter; however, the two-stage cascade PFC structure is challenging to realize high efficiency since the energy is transferred twice. To achieve high power factor, high efficiency, and low twice-line-frequency ripple, a hybrid quasi-single-stage (QSS) AC-DC converter is presented in this paper, which consists of a dual output hybrid Boost/Flyback PFC converter and a Buck ripple compensation circuit (RCC). The fundamental principles of the proposed converter and the critical conditions of operation mode transition are discussed in the paper. To confirm that the twice-line-frequency ripple is effectively suppressed, the small signal model of Buck RCC is built and analyzed. Moreover, the main characteristics, including operation mode transition angle, input current, power factor, and switching frequency of the proposed hybrid QSS AC-DC converter, are analyzed. By building a 120 W experimental prototype to validate the feasibility of the proposed hybrid QSS AC-DC converter, the experimental results show that the proposed converter can realize PFC function with high efficiency and extremely low twice-line-frequency output voltage ripple. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract—Shunt active power filters are the most promising solution for power quality challenges. It injects compensating current at the point of common coupling to recede harmonic content and to attain unity power factor. The proposed control strategy comprises of (a) Model predictive control (MPC) for switching state selection and (b) Sliding-window Discrete fourier transform (SDFT) technique for computing reference compensating current in a four-legged shunt active power filter. This paper incorporates MPC and SDFT control as a single-step algorithm for a four-leg inverter. The absence of modulator, look-up tables and complex mathematical operations support the easy implementation of the proposed controller digitally. The proposed scheme involves unique features like improved cost function in MPC, flexible sampling window size in SDFT, reduced computational complexity and execution time. Also, the compensation principle of the controller requires only line current measurement in contrast to the classical compensation techniques which require the distortion level and reactive power demand of the load. The efficacy of the proposed control method is tested for steady-state, dynamic conditions and parameter uncertainties. The system is validated by simulation using level-2 S-function block in MATLAB/Simulink for various case studies. [ABSTRACT FROM AUTHOR]

This study presents an enhanced AC drive for the SynRMs coupled with a circulation pump (CP) and an improved control system based on the field orientation. A grid-fed 900 W motor driver consisting of an electromagnetic interference filter (EMI), power factor correction (PFC), and three-phase inverter is designed to drive 0.75 kW SynRM. A boost PFC converter is designed as an interface between the AC power line and the motor drive. PFC is used to recover the bad power factor performance of the SynRM. In addition, the boosted and well-regulated DC-link voltage improves the motor driving performance. Control strategies and practical implementation based on the field-oriented control of synchronous reluctance motors are presented. Dynamic and steady-state responses of the CP SynRM drive in various conditions are verified experimentally. Low current and voltage ripples, unity power factor, maximum torque per ampere with low fluctuation and low EMI noise are achieved with the low cost efficiently. All of the improvements are obtained by fewer circuit elements and higher energy conversion efficiency. The advantages of using SynRMs in dry-rotor circulation pumps for heating applications have been demonstrated experimentally. [ABSTRACT FROM AUTHOR]

In this study, a model predictive control (MPC) technique is applied to a packed-u-cell (PUC)-based dual-output bidirectional electric vehicle (EV) battery charger. The investigated topology is a 5-level PUC-based power factor correction (PFC) rectifier allowing the generation of two levels of DC output voltages. The optimization of the MPC cost function is performed by reducing the errors on the capacitors' voltages (DC output voltages) and the grid (input) current. Moreover, the desired capacitors' voltages and peak value of the input current are considered within the designed cost function to normalize the errors. In addition, an external PI controller is used to generate the amplitude of the grid current reference based on the computed errors on the capacitors' voltages. The presented simulation and experimental results recorded using a 1 kW laboratory prototype demonstrate the high performance of the proposed approach in rectifying the AC source at different levels (dual rectifier), while drawing a sinusoidal current from the grid with low THD (around 4%) and ensuring a unity power factor operation. [ABSTRACT FROM AUTHOR]

Studies have shown the efficiency benefits of DC dis- tribution systems are largely due to the superior performance of DC/DC converters. Nonetheless, these studies are often based on product data that differs widely in manufacturer and operating voltage. This work develops a rigorous loss model to theoretically compare the efficiency of a DC/DC and an AC/DC PFC boost converter. It ensures each converter has the same components and equivalent operating voltages. The results show AC boost converters below 500 W to have 2.9 to 4.2 times the loss of DC.

Abstract This paper presents a simple three‐dimensional space vector modulation method in ghγ coordinates for a three‐level four‐leg neutral‐point‐clamped inverter. The idea uses redundant vectors as centre points to establish two‐level space vector diagrams simplifying the original space, the first sector of which is designated as subspaces, where a modulation process is implemented. The duty cycle and all possible switching sequences in a tetrahedron can be calculated automatically without manual storage and can avoid a full‐scale search process. Additionally, the neutral point potential can be balanced by three types of charge through cancellation. Such features enable the inverter to demonstrate good performance under closed‐loop control. Moreover, the proposed method can be applied to a multilevel inverter. Simulation and experimental results demonstrate the effectiveness of the proposed concept.

The increasingly extensive use of non-linear loads, mostly including static power converters, in large industry, commercial, and domestic applications, as well as the spread of renewable energy sources in distribution-generated units, make the use of the most efficient power quality improvement systems a current concern. The use of active power filters proved to be the most advanced solution with the best compensation performance for harmonics, reactive power, and load unbalance. Thus, issues related to improving the power quality through active power filters are very topical and addressed by many researchers. This paper presents a topical review on the shunt active power filters in three-phase, three-wire systems. The power circuit and configurations of shunt active filtering systems are considered, including the multilevel topologies and use of advanced power semiconductor devices with lower switching losses and higher switching frequencies. Several compensation strategies, reference current generation methods, current control techniques, and DC-voltage control are pointed out and discussed. The direct power control method is also discussed. New advanced control methods that have better performance than conventional ones and gained attention in the recent literature are highlighted. The current state of renewable energy sources integration with shunt active power filters is analyzed. Concerns regarding the optimum placement and sizing of the active power filters in a given power network to reduce the investment costs are also presented. Trends and future developments are discussed at the end of this paper. For a rigorous substantiation, more than 250 publications on this topic, most of them very recent, constitute the basis of bibliographic references and can assist readers who are interested to explore the subject in greater detail.

In this paper, a DC power supply is presented that, in addition to a power factor correction, is equipped with an active power filter function. This function enables compensation of both the reactive and the distortion power, generated by an external load, which is connected to the same power line node as the presented device. A tuneable inductive filter is added at the input of the power electronics controlled current source, which constitutes the main block of the power supply. This filter allows for a visible improvement in the quality of the current source control, compared to a similar device with a fixed inductive filter. This improvement depends on extending the “frequency response” of the current source, which facilitates an increase in the dynamics of changes in the input current of the power supply. The actual modification to the presented device is related to its control section, which is equipped with analogue regulators. The main purpose of this work is to present the results from a simulation model of an electrical system with a power supply, especially compared to those from a similar device but with a discrete control. The work represents a continuation of a research cycle on DC power supplies that are equipped with a power compensation function and are based on tuneable magnetic devices.

This paper investigates the design and implementation of a new single‐phase sensorless power factor corrected (PFC) circuit. Here, the inductor‐current sensor and its sensing circuit are removed. As a result, the cost and volume of the PFC circuit are effectively reduced. Two different methods, including an inductor‐voltage estimation method and an inductor‐current estimation method, are proposed and compared. To improve the dynamic responses of the PFC circuit, predictive voltage control and predictive current control are implemented here. A digital signal processor, type TMS‐320F‐2808, manufactured by Texas Instruments, is used here as the control centre to execute the sensorless methods and control algorithms. A 400 W, 50 kHz switching frequency, single‐phase alternating current (AC) 110 V /DC 300 V PFC circuit is implemented. The measured results validate the feasibility and correctness of the proposed methods. This proposed sensorless PFC circuit can be widely applied in industry due to its simplicity. [ABSTRACT FROM AUTHOR]

Summary: Power solutions contribute a remarkable role in all the sectors. In order to develop the sustainable and affodable power solution, the bettered power quality (PQ) based modified bridgeless switched inductor (MBSL) Sepic power factor correction (PFC) converter is introduced in this article. An added feature to an already existing traditional Sepic converter resulted in switched inductor (SL) network that reasonably improves the step‐down voltage gain with low current stress across the output inductors and diodes which restricts the utilization of transformer that ultimately reduces the overall cost of power solution. This introduced structure acts as a good choice of low‐cost power conversion solution in the perspective of improved inline PQ indices, high efficiency and good reliability. Furthermore, the discontinuous conduction mode (DCM) functioning of SL network reveals the innate zero current switching (ZCS) capability with enhanced efficiency. Besides, the effective functionality of the one‐stage PFC converter is tested on hardware prototype of 250 W/48 V, and it also adopts an appropriate control approach to stabilize the output voltage. This study also exposes small signal modeling to prove the stability of the power solution. In addition, the test outcomes reveal that the preferred PFC procure sinusoidal current from the AC mains that confirms the good enshaping attribute and low current harmonic distortions within the stipulated IEC 61000‐3‐2 standard guidelines for both standstill and fluctuating conditions. [ABSTRACT FROM AUTHOR]

The development of modern electronic systems and increasing number of application areas (computers, office equipment, rectifiers, converters, speed control devices, uninterruptible power supplies, switched power supplies) has led to harmonic generation and reduced energy efficiency. The majority of loads are inductive in nature and the draw of reactive power has increased in networks and transmission lines resulting in problems with power quality. In addition to efficient power flow in transmission systems, there is also a need to compensate for the reactive power flow in order the meet the requirements of the load and system. As an alternative to traditional solutions, FACTS (Flexible Alternating Current Transmission Systems) has been developed in order to operate electrical systems efficiently and improve stability and power quality. Technological applications such as SVC, STATCOM, SSSC and active harmonic filter are becoming widespread in order to improve power quality. In this study, applications within the scope of FACTS systems are explained and analysis of a fixed capacitor-thyristor controlled reactor (FC-TCR) to improve power factor is discussed. A circuit model of the FC-TCR is developed as a simulation and used to investigate how power factor may be kept within desired limits by adjusting the firing angle of the thyristors under different load conditions. A comparative evaluation has been carried out to determine the effect of FC-TCR by presenting results before and after the load compensation process is applied. From the simulation it is observed that reactive power compensation can be achieved even for varying linear loads. [ABSTRACT FROM AUTHOR]

This article analyzes circulating current control in single-phase power electronic converters, focusing on two different topologies: interleaved and parallel configurations. The study involves a bridgeless interleaving topology with two boost converters for increased efficiency. A parallel connection is also examined for monitoring line current, circulating currents, and power factor control. The article widely explains all current loops, including Common Mode Circulating Currents (CMCC) in the bridgeless interleaved topology and Differential Mode Circulating Currents (DMCC) in parallel-connected interleaved power converters. The proposed control scheme employs voltage and current control loops for output voltage and line current control and introduces CMCC and DMCC compensators to eliminate all types of circulating currents. An efficient Power Factor Correction (PFC) and output voltage control method is presented in this article. The effectiveness of the proposed schemes is validated through comparisons with modern control systems. The results are verified using Simulink/MATLAB and experimental setups with TI Instruments Piccolo prototypes and C2000 (TMS320F28035 microcontroller MCU) microcontrollers in parallel configurations. [ABSTRACT FROM AUTHOR]

In low‐voltage distribution systems, the increased penetration of power electronic devices leads to the decentralization of harmonic sources, which puts the sensitive loads or communication systems in the risk status. The conventional methods of point‐to‐point harmonic control are not applicable. In order to solve this problem without increasing additional investments, this paper focuses on mitigating the harmonic interference through the power factor correction (PFC) converter. Hence, a critical conduction mode (CRM) single‐phase boost PFC converter with adaptive harmonic compensation (AHC) control is proposed to reduce the harmonic interference at user side. Firstly, the feed‐forward control loop of a PFC converter is decoupled into the fundamental branch and harmonic branch to trace the harmonic interference and generate the compensation current. Then the compensation gain is designed by the compensation loop gain and compensation capacity of PFC converter. Meanwhile, the characteristics of the PFC converter are analyzed to study the effect of the AHC control on the active power transmission and output load, which can provide important support for the proposed method in application. Finally, a 160‐W experimental prototype is built to verify the effectiveness of the proposed AHC control. [ABSTRACT FROM AUTHOR]

A novel approach to the design of power factor correction (PFC) and torque ripple minimization in a brushless direct current (BLDC) motor drive with a new pulse width modulation (PWM) technique is demonstrated. The drive was designed to have a better power factor (PF) and less torque ripple. On the other hand, the modified Zeta converter is used to enhance the power factor of the proposed system. The modified Zeta converter is operated in discontinuous inductor current mode (DICM) by using a voltage follower technique, which only needs a voltage sensor for power factor correction (PFC) operation and DC-link voltage control. The output voltage of the VSI is determined by switching patterns generated by the PWM-ON-PWM switching strategy, and it reduces the torque ripples. The proposed drive is developed and simulated in a MATLAB/Simulink environment. The power factor of 0.9999 is produced by the PFC modified zeta converter topology and the PWM-ON-PWM scheme reduce the torque ripple in the commutation region by 34.2% as compared with the PWM-ON scheme. This demonstrates the effectiveness of the suggested control method. [ABSTRACT FROM AUTHOR]

Summary: Light emitting diode (LED) driver systems are now moving toward reduced processing power to improve conversion efficiency in indoor and outdoor applications. LED drivers connected to a single‐phase supply must meet the requirements for power factor correction with lower input current harmonics to maintain the alternating current (AC) power grid's quality and maintain a constant current through the LED load to eliminate the flickering effect in the light output. An LED driver is required to fulfill these requirements. In this paper, a new reduced processing power LED driver is proposed. By splitting the output capacitor into two capacitors and with the help of hardware design, the processing power can be reduced by using fewer semiconductors than in earlier designs. The proposed driver employs a simple ripple cancellation control approach to eliminate the 100 Hz ripple in the LED load current. Using this principle, an LED driver was designed and tested. The experimental results demonstrated that the proposed LED driver achieved an input power factor close to unity with lower input current harmonics and 92.5% of peak efficiency when operating at full power. [ABSTRACT FROM AUTHOR]

For low-power applications, this paper presents the development and design of a compact and ultra-highly efficient half-bridge LLC resonant converter. By using Galium Nitride (GaN) devices and high-efficient magnetics, the efficiency and power density of resonant converters can be improved. Compared to Silicon MOSFETs, GaN high-electron-mobility transistors (GaN HEMT) have a lower output capacitance and gate charge, resulting in lower driving loss and shorter dead times. Consequently, the proposed LLC converter based on GaN devices has excellent performance characteristics such as ultra-high efficiency, low switching losses, compact size, high voltage endurance, high operating temperature and high operating frequency. Furthermore, the proposed resonant converter features soft switching properties that ensure that the switches and diodes on the primary side are always switched at zero voltage and current. By doing so, LLC resonant converter switching losses are significantly reduced by up to 3.1%, and an overall efficiency of 98.5% is achieved. The LLC resonant converter design with GaN HEMT has great advantages over Si MOSFET solution regarding efficiency, overall losses, switching loose and power factor correction. A 240 W, 240 V to 60 V half-bridge GaN HEMT LLC resonant converter is simulated with a switching frequency of 75 KHz, along with the comparative analysis of the Si metal oxide semiconductor field effect transistor (MOSFET) solution. Moreover, the design and analysis of highly efficient magnetics with a power factor of 0.99 at full load is presented. A 240-Watt single stage LED driver with power factor correction is also designed to verify and compare the performance of proposed LLC resonant converter. [ABSTRACT FROM AUTHOR]

Wireless Power Transfer (WPT) particularly in the field of Electric Vehicle charging applications has wide research opportunities because of its huge growth. The power transfer efficiency is of major concern and researchers are finding ways to improve it by reducing stages of the WPT and making it better than the wired EV charging method. The increasing penetration of charging stations in the grid brings many challenges and hence to find a suitable control scheme to enhance input power quality. For the most optimal operation and comprehensive support, the charging systems must incorporate a suitable converter topology, a well-defined control strategy, and comply with all relevant grid codes and standards. For smooth and efficient functioning these features must be included in the EV charging systems. This paper presents a review of single-stage topologies and the power factor correction methods employed for EV wireless charging. An overview of different charging methods is first presented then the AC input and DC input single-stage converter are discussed, and following that methodologies for improving power factor correction are reviewed with the comparative analysis from different literatures. Finally, the challenges in single-stage wireless power transfer (SSWPT) were addressed and the future scopes were discussed which provides the future research directions.

Several power decoupling techniques have been studied in the specialized literature to reduce or eliminate the ripple at 120 Hz intrinsic to the nature of single-phase AC-DC converters. Among these techniques are the active decoupling circuits, which insert new switches and passive elements in the circuit to increase costs and losses in the converters. The complete single stage (CSS) of power decoupling is defined in this study. The switches responsible for controlling the power factor in the proposed converter also control the output voltage and the ripple at 120 Hz using the phase-shift technique. Thus, lower-value capacitors can be used, allowing the replacement of the widely used electrolytic capacitors with film capacitors, which have a long useful life compared to the former. In addition, the proposed converter is isolated and has high efficiency. Simulation and experimental results are presented for a 1 kW prototype with an efficiency of up to 93%, showing that power decoupling is obtained, and the CSS topology definition can be incorporated into the literature.

Latest developments in low voltage wide-bandgap semiconductor technology have increased the popularity of single-phase multi-level (ML) totem pole (TP) power-factor correction (PFC) converters. Phase shifted flying capacitor based power stages offer several advantages, such as higher input current ripple frequency, smaller size inductor and differential mode (DM) filter, and usage of low voltage Gallium Nitride (GaN) devices with better figure-of-merit. Even though it has been proven that ML TP PFC converters have good power density and efficiency, the determination of optimal voltage levels and switching frequency requires a system-level optimization. This paper proposes an optimization framework for ML TP PFC converters, taking the power stage, thermal, DM filter, and magnetic designs, as well as practical design considerations, into account to determine the voltage-levels and switching frequency that minimize the power losses, cost and volume of the total system. To process output power of 3700W, the optimization tool suggests using a 4-Level GaN TP PFC topology switched at 45 kHz. The outcome of the tool has been compared with other fixed inductor current ripple designs, as well as optimized designs for 3-Level and 5-Level TP PFC converters in terms of cost, volume, and power losses. In accordance with the optimization results, a prototype of a 4L TP PFC rated at 3700 W is designed, which achieves a peak efficiency of 99.6% at 1 kW and> 99.1% efficiency under the full power range.

Electric vehicles (EVs) are getting more popular in automobiles due to environmental factors. Since electric vehicles manage their power from the rechargeable battery, therefore, it’s essential to have a reliable, efficient, and economical battery charger to provide stable required output for the specified EV’s battery. In this paper, a DC-DC converter with a modified PI controller has been presented which helps to achieve the required output voltage and high current density with negligible overshoot for the specified lithium-ion battery system to minimize the charging time. Apart from minimizing the power loss of the active switches, the proposed system minimizes the junction temperature eventually improving the life cycle of the converter. The analysis of the proposed converter is performed both in ideal and non-ideal conditions. The power loss of the active switches and the junction temperature have also been analyzed. An effective and economical dc and ac side inductors have been designed and analyzed the performance of total power loss and temperature rise. The results show that the proposed converter can maintain a power factor around 90% and a total harmonic distortion around 0.46%, which is ideal for the high-density load current. The reliability of the dc-dc converter is also evaluated. A hardware prototype has also been implemented to confirm its viability for EV battery charging applications.

Power factor correction (PFC) is usually realized with a boost converter in a traditional power converter. This paper introduces a PFC modulated WPT method which can realize PFC function through phase-shift modulation of the primary-side inverter of a series-series (SS) WPT system. A close-loop control method of the phase-shift modulated system is also proposed for practical implementations. Without using a PFC converter, the structure of a WPT system can be simplified. Theoretical analysis and experimental results are provided to verify the idea.

ABSTRACTThis research paper proposes an enhanced power quality in bridgeless modified Landsman-Canonical switching cell (BMLCSC) converter used for arc welding power supplies. This proposed converter topology is presented for circuit component reduction to eliminate the need for a diode bridge rectifier and input filter to make the circuit more compact. The proposed converter is operated on discontinuous conduction mode (DCM). A closed loop PI control circuit with a single voltage sensor is utilized to achieve load regulation, line regulation with high efficiency and quick response. The exploratory performance of preferred framework is simulated using Matlab/Simulink and validated with a hardware prototype of 100 W, 48 V.