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In a single phase, two-stage photovoltaic (PV) grid-connected system, the transient power mismatch between the dc input and ac output generates second-order ripple power (SRP). To filter out SRP, bulky electrolytic capacitors are commonly employed. However, these capacitors diminish the power density and reliability of the system. To address this issue, this paper introduces a power decoupling method. This method utilizes a bidirectional buck–boost converter, connected in parallel to the DC link, to divert SRP to a small capacitor within the single-phase grid-connected PV inverter, eliminating the need for electrolytic capacitors. The proposed topology consists of a dc–dc stage, a decoupling stage and an inverter stage, where each stage is controlled independently. In consideration of the instantaneous power fluctuations on the filtering elements, the optimal voltage reference of the decoupling capacitor is derived and implemented in the proposed decoupling control strategy. Thus, the capacitance for decoupling is minimized and the volume of the inverter is reduced. Discontinuous current control is adopted to charge and discharge the decoupling capacitor, which simplifies the decoupling control design. Finally, the steady-stage and dynamic responses of the proposed inverter are validated by simulation and experimental results in a 1-kW PV prototype. [ABSTRACT FROM AUTHOR]

Battery storage systems are becoming very popular around the world. However, they are mainly used in industry for high-performance applications. Domestic use is still sporadic due to size and cost issues. This work overviews basic conceptual designs for a cost-effective battery storage system. The main specificity of the proposed systems is the use of commonly available recycled batteries from household appliances such as laptops and backup power supplies. The circuit topology considered is a 3S (three cells in series) configuration. This is because such wiring arrangements are those that are most often found in the home appliances described here. The technical solutions of the device itself focus on the ratio of the efficiency of the whole system to the production cost. Given the above, attention was paid to the simulation analysis of the operating modes, which directly influenced the components' price. Changing the switching control scheme of the power transistors makes it possible to reduce the requirements for the driving components used with minimal impact on the power conversion efficiency (Δη 1–4%). According to the established findings, a prototype was made on which the simulation findings were verified; then, we further focused on the experimental measurement of the efficiency of the MPPT converter and conducted an analysis of a methodology in which we measure the deviation from the actual point of maximum power. The simple possibility of parallelizing the individual storage devices will again help improve the system's overall efficiency. This makes the system suitable for use in small spaces such as houses, garages, cellars, etc. [ABSTRACT FROM AUTHOR]

This study explores an alternative method of generating electrical energy using a thermoelectric generator that utilizes heat from the soleplate of a steam iron and six thermoelectric units connected in series. Based on the Seebeck effect, the thermoelectric modules convert the temperature difference into voltage. An increase in the heat source temperature leads to higher voltage production by the series-connected thermoelectric modules, although the electrical power output depends on the connected load. The power generator design includes thermoelectric modules, a buck-boost converter, an 18650 lithium-ion battery, and a 5-watt, 12-volt DC lamp. The study addresses key aspects such as the impact of temperature on power output in series-connected and parallel-connected thermoelectric circuits, and the efficient conversion of heat from the steam iron soleplate into electrical energy. The research objectives are threefold: to determine power and temperature values for series-connected thermoelectric circuits, to evaluate power and temperature values for parallel-connected thermoelectric circuits, and to utilize heat from the steam iron soleplate as a thermoelectric heat source for generating electrical energy. Testing involved a buck-boost converter connected to a battery, producing 12.35 volts with a temperature difference of 49°C. Design enhancements, such as integrating heatsinks or coolers on the cold side of the modules to maintain a significant temperature differential, are critical for optimizing performance.

Abstract A new DC–DC buck–boost converter with a wide conversion ratio is presented in this paper. The proposed buck–boost converter consists of a combination of modified boost converter and ZETA converter, which has the advantages of both converters such as continuous input/output current and positive polarity of the output voltage. The combination of these two converters achieves semi-quadratic voltage gain and makes the proposed converter suitable for industrial and renewable energy applications. With a voltage gain higher than that of the ZETA converter and modified boost converter, the proposed converter also reduces input current stress due to its continuity. Two operating states are available for this converter in continuous conduction mode. This converter has two switches that operate simultaneously and can be easily controlled. The converter's output voltage ripple and output capacitor current stress are reduced as a result of continuous output current. Computational analysis and the introduced structure efficiency considering the influence of parasitic elements are presented in this paper. The small signal modelling and closed-loop control, as well as simulation and experimental results are also presented. This converter has also been compared with other similar and recently presented topologies. Finally, a 40–60 W, 20–76 V for boost mode and 10 V for buck mode prototype was implemented to verify the accuracy of the computational analysis.

This paper compares the performance of a Sliding Mode Control (SMC) and Proportional-Integral (PI) controller under different voltage and load conditions. The study's findings underscore the need to account for load variations in system designs and to continuously seek system optimization irrespective of the controller type chosen. PI controller demonstrates effectiveness under certain circumstances. However, significant drops in voltage and current during abrupt load changes are obtained. On the other hand, SMC enables superior adaptability, efficiently managing voltage transients and load variations without any electrical disturbances, thereby maintaining system stability. A comparative analysis further emphasizes the SMC's superior time response and robustness against reference voltage changes. Consequently, SMC is proven to be a preferable choice over the PI controller in systems experiencing frequent voltage and load variations. However, both controllers achieve the potential for further response time optimization and stability. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid method for controlling bidirectional power sharing among grids and dc microgrids. The interlinking converter (IC) and current-fed dual active bridge (CFDAB) converters connect the grid and dc microgrid. The proposed approach is the joint implementation of golden eagle optimization and radial basis function neural network, hence, named the GEO-RBFNN approach. The bidirectional power distribution control signal analysis significantly diminishes power distribution deviation and circulating current. This power-sharing control system neglects the need for battery backup since the required amount of power is brought from or handled by an AC utility. The dc microgrid incorporates the dc to dc converter, from which boost converters use sources and buckconverters use supply loads. The control of bidirectional power sharing among the microgrids and the grid is attained with the aid of the GEO-RBFNN algorithm. It delivers certain aids, like higher predictability, highly reliable results, high speed, and less complexity. The outcome is investigated on the MATLAB platform. According to the comparison outcome, the proposed method delivers higher performance than the existing system. The proposed method gives higher comparison outcomes than the current methods, which can conquer the associated problems. The proposed method-based settling time is 3.356 ms, and the rise time is 1.555 ms. The efficiency based on the proposed method is 97.54%, which is higher than the existing methods. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to improve the efficiency and performance of a new proposed buck–boost converter. The buck–boost converter allows for voltage step‐up or step‐down operations, making it suitable for wide range applications. The proposed converter design incorporates innovative circuitry to enhance the overall system efficiency. Based on the findings, a new buck–boost converter topology is introduced, which offers improved voltage regulation, reduced losses, and increased power conversion efficiency compared to traditional converter designs. Simulation studies and experimental validations are conducted to assess the performance of the proposed new buck–boost converter. The results demonstrate significant improvements in power output and system stability of proposed converter compared to conventional converter configurations. [ABSTRACT FROM AUTHOR]

The current research introduces an enhanced buck converter. The introduced converter improves the performance of similar converters thanks to causing lower switch voltage stress, higher efficiency and fewer number of elements. To make use of low voltage MOSFETs with a smaller ON resistance, using multiple switching strategies would reduce the voltage stress across the switch and thus allow them to be used. This study compares the performance of the proposed converter with the similar converters. The gate pulses are similar in the proposed converter, so the control is very simple. Input voltage is divided between the blocking capacitors at the input and as a result, the voltage stress on the switches is lower than the input voltage. So, the converter can be designed with MOSFETs with low drain-source resistance. Also, the voltage gain is reduced in comparison with the conventional buck converter. Furthermore, output power is shared between two switches which results in better heat dissipation. Also, it is possible to implement the proposed converter using a single magnetic element. Therefore, the total number of components in comparison with similar converters is reduced. The results show that the introduced converter technically performs with lower switching losses and increased overall efficiency discussion of operating modes, as well as converter design and test results shall be provided. [ABSTRACT FROM AUTHOR]

Buck-boost converters are one of the important devices in power conversion applications that are capable of increasing or decreasing the voltage according to the load requirements. However, the main challenge in operating a buck-boost converter is maintaining the stability of the output voltage. The selection of PID control is one of the ways that can be used to keep the output voltage stable, in this study, buck boost with 12 volts input is used and PID control is set with several parameters that can reduce errors and stabilize the output voltage, the PID constant values are Kp = 2 and Ki = 0.2 with these parameters obtained less stable results with time rise = 72.45 ms and overshoot = 0.995 % for boost mode with voltage 24 volt output and time rise = 123.2 ms and overshoot = 0.995 % for buck mode with an output voltage of 5 volts. Thus, to maximize the system with a stable output voltage, a fuzzy logic control is used which has an adaptive time response and is able to adapt to load variations, the simulation results show that the output voltage of the fuzzy logic control has a time rise = 114 ms and overshoot = 0.761 % in boost mode and time rise = 104 ms with overshoot = 0.971 % in buck mode. The advantage of fuzzy logic control is that it is more optimal and able to improve system performance responsively compared to other conventional controls. [ABSTRACT FROM AUTHOR]

This article introduces a wide input range buck‐boost Light Emitting Diode (LED) driver designed for industrial and street lighting applications. The driver characterized by a continuous input current with less ripple and common ground between input and output featuring non‐inverting voltage at the output, suitable for green energy sources. The proposed topology achieves a high voltage conversion ratio which is a blend of quasi‐Z source boosting followed by conventional buck with enhanced step‐down voltage capability. Furthermore, the driver maintains a constant voltage at the load terminal for diverse source voltage variations by adapting the inherent buck‐boost nature. Also, the driver operates with low duty ratio results in lower voltage, current stresses and conduction losses. The steady state and design analysis of the proposed LED driver is carried out for an input voltage range from 24 to 96 V. An experimental prototype of 200 W/71 V LED driver is validated in the laboratory for wide input voltage. There is a high concordance exists between the theoretical analysis and experimental results of the proposed topology. [ABSTRACT FROM AUTHOR]

This article presents a coordinated control method used for wireless power transfer (WPT) systems. This method can improve WPT system transmission efficiency while maintaining the constant output voltage. First, the topology of the DC–DC converter is selected and the equivalent circuit model of the WPT system is established. Then, the WPT system characteristics are discussed and the mutual inductance estimation process is presented. Furthermore, the coordinated control method is proposed, where the constant voltage output is achieved by connecting the Buck–Boost converter after the diode rectifier. Meanwhile, the optimal phase shift angle is calculated and sent to the controller to achieve maximum transmission efficiency tracking control, according to the measured load voltage and current. Finally, simulations and experiments are adopted to verify the proposed coordinated control method. The experimental results indicate that the average system transmission efficiency is increased by 1.80% and the efficiency fluctuation is decreased by 2.67% when the system load resistance varies, while the average system transmission efficiency is increased by 1.80%, and the efficiency fluctuation is decreased by 3.14% when the mutual inductance changes. This means the proposed coordinated control method is effective under the conditions of the WPT load and mutual inductance variations. [ABSTRACT FROM AUTHOR]

Summary This paper presents the symmetric differential Buck–Boost converter, obtained from the differential connection between two Buck–Boost converters. The topology is characterized by presenting low‐voltage ripple, partial power processing, ability to provide intermediate voltage gains (1 < M < 10) and design simplicity. In this configuration, the output voltage is composed of the sum of the input voltage and the output voltages of both converters differentially connected. The topology description along with its main equations and waveforms in continuous conduction mode with phase‐shift modulation are presented in this paper. Moreover, a mathematical analysis that demonstrates its capability of performing with partial power processing and a comparative analysis with similar topologies are also presented. In addition, experimental results extracted from a prototype are presented and discussed. Because the proposed converter is applied to photovoltaic energy processing, it is validated in open loop and as maximum power point tracker, in which the obtained CEC efficiency is 97.8%. [ABSTRACT FROM AUTHOR]

A novel integrated DC-DC converter is proposed for the first stage of two-stage grid connected photovoltaic (PV) systems with energy storage systems. The proposed three-port converter (TPC) consists of a buck–boost converter, interposed between the battery storage system and the DC-AC inverter, in series with PV modules. The buck–boost converter in the proposed TPC is utilized for maximum power point tracking by regulating two power switches. The output power of the proposed converter is regulated by controlling the DC-AC converter. During the battery-charging mode, partial power regulation is employed with a direct power flow path (the series-connection of the PV panel, the battery and the output). As resistances in this path are almost negligible, the power conversion efficiency is higher than existing topologies. During battery-discharging mode, the power conversion is processed through a buck–boost converter with only two active power switches and one inductor. With fewer components, higher power conversion efficiency is also achieved. The circuit operation and analysis are presented in detail. To illustrate the simplicity of the converter control, the performance of the converter is tested with a straightforward maximum power point tracking on a PV system with battery cells. Simulation and experimental tests are carried out to demonstrate circuit operation and power conversion efficiency. [ABSTRACT FROM AUTHOR]

Multiple-Input Buck–Boost (MIBB) dc–dc converters receive energy from two or more energy sources that can Deliver Several Outputs of variable power. There are situations in which it is advantageous to use a buck-boost converter, i.e., when there is no guarantee that the input voltage will always be higher or always lower than the output voltage. This happens for example when there is an input voltage in an inverter that makes the interface between the photovoltaic panels or wind generators and the electrical grid. Here, we present a trigger-controlled MIBB converter topology with various input voltage sources and energy diversification of 0–100% of each source, determined by a pre-determined arbitrary value. The full-range linear transfer function of the controller drives the closed-loop MIBB system to operate as a linear single-input buck–boost converter. The response time of the controller is about 400 μs and therefore allows for high-speed real-time control. The intelligent fixed frequency switching strategy overcomes the limitations of present multiple-input converters by switching period sharing. System performance was verified by simulations and an experimental setup with two source inputs. It is shown that the system can be treated as a linear system, controlled by a single parameter—K. As a result, a simple to control MIBB system with a wide input/output range and fast response time is presented. [ABSTRACT FROM AUTHOR]

DC-DC converters are an important class of power electronics due to their wide use in various applications as sources of efficient power supplies. They step down or step up the applied voltage so that it is always either lower or higher than the supplied voltage. This is crucial in power delivery and portable systems, especially in battery-operated systems. The purpose of the paper is to investigate how the efficiency of Buck-Boost converters improves by using sliding mode control when operating under different conditions. The work aims to develop a control strategy that increases the efficiency and reliability of Buck-Boost converters, employed in a myriad of power electronics applications. The research focuses on a sliding mode control approach to overcome the challenges of nonlinear dynamics and susceptibility to external disturbances. The methodology involves studying the behavior of the converter under different conditions such as changes in loads, input voltage variations, and reference voltage changes. The study uses theoretical modeling and simulation to evaluate the concept of sliding mode in addressing the challenges for improved efficiency. Such investigations show how sliding mode control improves efficiency. SMC approach reduces the response time by 5%, improves efficiency by 3%, and enhances overall stability under fluctuating conditions. The use of sliding mode control enhances the converters against disturbances and provides an efficient voltage regulator. The research is useful to the field as it offers more insights into the control strategy that significantly improves the performance of converters concerning efficiency and stabilization. [ABSTRACT FROM AUTHOR]

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Abstract Considering different applications that require varied power and voltage conversion levels between AC grids and AC loads, AC–AC power conversion between AC grids has become an inevitable technology of energy management systems. An isolated converter for performing AC-to-AC transmission is proposed with minimal components for reduced losses and enhanced system efficiency. Single-phase direct buck-boost AC to AC converter with minimum components constituted with two dual IGBT control units (IGBT 1–IGBT 4), inductor (Lf), and capacitor (Cf) is proposed in this work. The MATLAB/Simulink platform is used to provide in-depth analysis of the circuit and components along with the design guidelines, and simulation outcomes of this proposed model. The voltage gains of G = 2.13, power factor of 0.97, and overall efficiency of 98% are achieved in the proposed system with minimum components of 4 switches, 2 conductors, and 1 capacitor and inductor respectively. The obtained results are compared with existing technology to evaluate the proposed system.

Battery storage systems are becoming very popular around the world. However, they are mainly used in industry for high-performance applications. Domestic use is still sporadic due to size and cost issues. This work overviews basic conceptual designs for a cost-effective battery storage system. The main specificity of the proposed systems is the use of commonly available recycled batteries from household appliances such as laptops and backup power supplies. The circuit topology considered is a 3S (three cells in series) configuration. This is because such wiring arrangements are those that are most often found in the home appliances described here. The technical solutions of the device itself focus on the ratio of the efficiency of the whole system to the production cost. Given the above, attention was paid to the simulation analysis of the operating modes, which directly influenced the components’ price. Changing the switching control scheme of the power transistors makes it possible to reduce the requirements for the driving components used with minimal impact on the power conversion efficiency (Δη 1–4%). According to the established findings, a prototype was made on which the simulation findings were verified; then, we further focused on the experimental measurement of the efficiency of the MPPT converter and conducted an analysis of a methodology in which we measure the deviation from the actual point of maximum power. The simple possibility of parallelizing the individual storage devices will again help improve the system’s overall efficiency. This makes the system suitable for use in small spaces such as houses, garages, cellars, etc.

This paper investigates the design of a robust non-linear backstepping controller for the DC-AC microgrid comprising a photovoltaic source and a battery energy storage system with grid integration, all feeding a non-linear load, to improve its power quality and dynamic stability. A unidirectional DC-DC boost converter and a bidirectional back boost converter are used on the DC side to connect the photovoltaic module and battery storage to the DC bus. The three phases of the voltage source inverter are connected to the electrical grid via an inductive filter on the AC side. The control objectives are fourfold: i) Produce the maximum power from the photovoltaic system regardless of variations in weather conditions (temperature and irradiation); ii) Keep the DC link voltage constant and close to a given reference value under various conditions to ensure a balance of power between the DC and AC sides; iii) Active power control by injecting excess power into the grid; iv) Propose an energy management strategy to optimize the energy consumption of each source: the solar source, the grid, and the battery storage. Simulation results under different operating conditions, parameter variations, and load disturbances are presented and discussed to verify the performance satisfaction of the proposed controllers. An improvement in the overall dynamic performance of the microgrid is demonstrated, with a reduction in voltage overshoot (4.8%) and settling time (5.6ms) on the DC bus, along with reduced total harmonic distortion (THD) in grid current (0.29%) when compared with the other controllers in this work: the proportional integral controller (voltage overshoot (5.8%), settling time (15.5ms); grid current THD (6.53%)) and sliding mode controller(voltage overshoot (4.6%), settling time (15ms), grid current THD (3.53%). finally, several tests have been conducted on the proposed microgrid to evaluate the controller's efficiency in maintaining power balance during irradiation distortion and non-linear load imbalance. [ABSTRACT FROM AUTHOR]

Considering different applications that require varied power and voltage conversion levels between AC grids and AC loads, AC–AC power conversion between AC grids has become an inevitable technology of energy management systems. An isolated converter for performing AC-to-AC transmission is proposed with minimal components for reduced losses and enhanced system efficiency. Single-phase direct buck-boost AC to AC converter with minimum components constituted with two dual IGBT control units (IGBT 1–IGBT 4), inductor (Lf), and capacitor (Cf) is proposed in this work. The MATLAB/Simulink platform is used to provide in-depth analysis of the circuit and components along with the design guidelines, and simulation outcomes of this proposed model. The voltage gains of G = 2.13, power factor of 0.97, and overall efficiency of 98% are achieved in the proposed system with minimum components of 4 switches, 2 conductors, and 1 capacitor and inductor respectively. The obtained results are compared with existing technology to evaluate the proposed system. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive exploration of an integrated Buck-Boost converter and Sliding Mode Control (SMC) Maximum Power Point Tracking (MPPT) system for optimizing photovoltaic energy conversion. The study focuses on enhancing solar energy extraction efficiency, regulating output currents, and ensuring effective battery utilization. Through a systematic analysis of converter component sizing and operational modes, the paper delves into the intricacies of the Buck-Boost converter. The unique contribution lies in the innovative integration of SMC with the traditional Perturb and Observe (P&O) algorithm, providing robust and adaptive MPPT under varying environmental conditions. Additionally, the paper introduces a battery management system with three distinct modes, namely, Charging, Direct, and Discharging, offering intelligent control over critical scenarios. Simulation results underscore the robustness of the proposed system under diverse conditions, demonstrating its effectiveness in managing power distribution based on battery charge levels, even in scenarios of insufficient solar power. Overall, this research significantly contributes to advancing the understanding of PV/battery systems and offers a practical, sustainable solution for optimizing energy production, distribution, and storage, marking a substantial stride towards a more efficient and sustainable energy future. [ABSTRACT FROM AUTHOR]

A compound anti-interference control method based on a high-order nonlinear disturbance observer (HONDO) is proposed to address the impact of system disturbances on output voltage when applying the Buck–Boost converter in a microgrid to provide power to loads. Initially, the dynamic circuit model of the Buck–Boost converter is formulated, taking into account the system disturbance. Subsequently, HONDOs are designed to provide real-time estimates of uncertain factors in both the voltage loop and current loop of the circuit. These estimates are then utilized to design backstepping controllers aimed at effectively tracking the load output voltage set point. The simulation and experimental findings indicate that, when faced with load mutations, input voltage variations, and uncertainties in system parameters, the proposed compound anti-interference control method outperforms traditional control techniques by offering superior response speed, broader disturbance estimation capabilities, and enhanced dynamic performance of the Buck–Boost converter. [ABSTRACT FROM AUTHOR]

Nowadays, the use of fuel cells in various applications has become very widespread. Some of their most important applications are in electric vehicles (EVs) and local off‐grid power systems. An EV works as an electric motor that burns a mixture of fuel and gases to generate electricity. One of the challenges with fuel cells is the slow dynamic response to load power changes. In the past few decades, the modeling and control of DC‐DC converters have undergone extensive research and development. However, the error, settling time, and peak overshoot performance are not reduced by the robust nonlinear controller and current mode controller. To overcome these problems, quantile regressive extreme seeking cat swarm optimized Mamdani fuzzy PI controller (QRESCSO‐MFPIC) approach is developed. The goal of the QRESCSO‐MFPIC approach is to reduce the integral time absolute error (ITAE) for tuning the fuzzy PI controller. Initializing the fuzzy PI controller parameter is an input in the QRESCSO‐MFPIC approach. For every parameter value, the fitness function is determined and quantile regression analysis is carried out. The efficiency of the QRESCSO‐MFPIC approach is measured by evaluating the settling time and peak overshoot. Tuning of the PI controller is carried out with cat swarm optimization (CSO) and particle swarm optimization (PSO) based on the objective function of ITAE. The result analysis shows that the QRESCSO‐MFPIC approach improves the efficiency of an optimized Fuzzy PI controller compared to the existing methods. Peak overshoot reduction and settling time are improved through the QRESCSO‐MFPIC approach than the proportional integral particle swarm optimization controller (PI‐PSO). [ABSTRACT FROM AUTHOR]

To solve the problem that the output voltage of the new energy power generation device varied greatly and it was difficult to realize energy storage, a novel single-switch coupled buck-boost converter based on PI controller and feed-forward control was presented. The voltage gain could be adjusted by the turns ratio of the coupled inductor, and the voltage stress on the power switch was suppressed by the passive clamped circuit with recycled leakage inductor energy. Compared with traditional buck-boost converter, the proposed converter had the advantages of wider voltage conversion ratio, continuous input current, and low voltage stress on power switch. Combing PI controller with feedforward control strategy, superior input transient response of the converter during the whole input volt age range is obtained. The operating principles and steady-state characteristics of proposed converter were analyzed and derived in detail, respectively, and the performances were compared with other single-tube buck-boost converters. The small-signal model was derived, and the correctness of PI parameter design was verified by bode diagram. The design process of PI controller combined with feedforward control strategy was analyzed. Finally, an experimental prototype with a rated power of 100 W, 20 V to 60 V input, and 48 V output was built to verify the performance of the proposed converter in boost mode and buck mode, and the feasibility of PI controller combined with feed-forward control strategy. The measured maximum efficiencies with the boost and buck modes were 97.08% and 97.10%, respectively. [ABSTRACT FROM AUTHOR]

Today, solar energy is used for various applications such as photovoltaic-powered light emitting diodes (LEDs) streetlights. Such systems are composed of a photovoltaic (PV) panel, a battery storage, and an LED light integrated with often two power conversion systems along with independent controllers. In this paper, a single unified bidirectional boost converter is used to manage a PV-powered LED streetlight. A simple and useful soft-switching bidirectional boost converter is considered by incorporating an LC series resonant tank into the conventional version. Both buck and boost operations are supported by the proposed topology. The converter stores PV energy in battery by operating in buck mode during the day, and the battery supplies the LED light at night by operating in boost mode. The system is controlled in both cases through a suitable control strategy for regulating voltages at converter input and output ports, MPPT for the PV panel, SOC for the battery, and light control of the LED. Due to the relationships between photo, electricity, and thermal, LED lights can be supplied at an optimal voltage, where the maximum luminous flux is achieved. The technique, utilized in this paper, drives the LED streetlight to achieve optimal luminous flux by using photo-electro-thermal (PET) theory and heatsink characteristics. The obtained values for luminous flux for two simulated conditions are 1551 and 2187 lm, respectively. The proposed LED streetlight system is analyzed and simulated utilizing MATLAB/SIMULINK software.

DC-DC converters are an important class of power electronics due to their wide use in various applications as sources of efficient power supplies. They step down or step up the applied voltage so that it is always either lower or higher than the supplied voltage. This is crucial in power delivery and portable systems, especially in battery-operated systems. The purpose of the paper is to investigate how the efficiency of Buck-Boost converters improves by using sliding mode control when operating under different conditions. The work aims to develop a control strategy that increases the efficiency and reliability of Buck-Boost converters, employed in a myriad of power electronics applications. The research focuses on a sliding mode control approach to overcome the challenges of nonlinear dynamics and susceptibility to external disturbances. The methodology involves studying the behavior of the converter under different conditions such as changes in loads, input voltage variations, and reference voltage changes. The study uses theoretical modeling and simulation to evaluate the concept of sliding mode in addressing the challenges for improved efficiency. Such investigations show how sliding mode control improves efficiency. SMC approach reduces the response time by 5%, improves efficiency by 3%, and enhances overall stability under fluctuating conditions. The use of sliding mode control enhances the converters against disturbances and provides an efficient voltage regulator. The research is useful to the field as it offers more insights into the control strategy that significantly improves the performance of converters concerning efficiency and stabilization.

Objectives. A DC/DC converter based on SEPIC topology is a unipolar electronic device which converts an input positive voltage into a stabilized output voltage of the same polarity. It also has the ability to regulate polarity both below and above the input voltage. The aim of the paper is to analyze the DC/DC converter in its both operation phases, as well as to draw up equivalent circuits and obtain characterizing differential equations using Kirchhoff’s rules for each phase. Each system of differential equations is reduced to Cauchy equations, in order to be further transformed into a limiting continuous mathematical model. Each system of equations is converted into a matrix form and subsequently combined into a single matrix system.Methods. The construction of a limiting continuous mathematical model was accomplished using Kirchhoff’s rules. Multisim software was used for the computer simulation, thus enabling the calculated results of direct currents and voltages to be compared to those of the simulation.Results. Results show that the phase coordinates of the mathematical model tend towards the values of real currents and voltages of the converter at a switching frequency higher than 200 kHz. Fairly good agreement is established between the calculated values of currents and voltages and the values obtained by simulation (with varying fill factor and switching frequency).Conclusions. The resulting limiting continuous mathematical model of the DC/DC converter based on SEPIC topology allows for an estimation of the dependence of the currents flowing through the inductor windings and the voltages across the capacitors on a number of parameters. The limiting continuous mathematical model of the DC/DC converter based on SEPIC topology is the basis for its circuit design and physical-and-mathematical analysis.

This paper proposes a soft-switched paralleled boost converter based LED driver for street lighting application. Output of paralleled boost converter (BC) in the form of full-bridge feeds a buck-boost converter (BBC). The outputs of paralleled BC and BBC are added to power LED lamps. The paralleled boost converters help in reducing the source current ripple with small inductors and also can handle large power. Regulation of the load voltage is achieved by BBC which handles small power without significantly affecting the overall efficiency. Soft switching of the devices in boost converters is achieved with a ZVS inductor resulting in high efficiency. PWM based dimming control is employed. The LED driver can be fed from batteries, ultra-capacitor, etc. A prototype of 65 W DC-DC converter for LED lighting is developed. The experimental results are in good agreement with simulation results. The proposed converter offers high efficiency of 93.42%, reduced source current ripple, and dimming control. Efficiency of the proposed converter with SiC MOSFETs is around 95% at all voltage variations.

This article delves into the hardware implementation of a buck-boost converter on a Texas Instruments C2000 board, tailored for impressed current cathodic protection to safeguard submerged metal structures against corrosion. Impressed current cathodic protection is vital for combating corrosion in buried or submerged metal structures, where a reliable power supply is crucial. The use of solar energy captured by photovoltaic panels emerges as an environmentally sustainable and economically viable solution for this critical application. The paper examines the design, hardware implementation, and system performance, focusing on the integration of the Texas Instruments C2000 board which is, pivotal for the automation and success of the impressed current cathodic protection system. The developed work aims to advance the sustainability of submerged metal structures by presenting a solution combining impressed current cathodic protection with the ecological advantages of solar energy.

This study proposes a novel approach to fast and direct determination of the Maximum Power Point (MPP) at any value of solar irradiation and cell temperature, without applying further mathematical processing to operate at that point. The current approach aims to reduce algorithm complexity, time consumption during the iteration, and oscillation to reach the point at which the panel generates maximum possible power. For avoiding or eliminating these drawbacks, the chopper duty cycle (D) at which the panel-generated power should be the maximum is determined using the panel datasheet with respect to voltage and power at different irradiation rates (G). Mathematical equations are derived for MPP voltage and power at any value of solar irradiation using the manufacturer Photovoltaic (PV) specification. The simulation results obtained by MATLAB/SIMULINK platform showed that the power had a linear change, while the voltage had a nonlinear one with narrow variations. The yield duty cycle controls the Modified Single Ended Primary Converter (MSEPIC) that regulates the load voltage through a wide range below and above the rated panel voltage. The simulation results showed the fast response of chopper operation with a negligible starting time required by the MPPT algorithm, no duty cycle oscillation, and shorter iteration time. Furthermore, the conducted approach is validated based on the data published in a reputed journal, and the obtained results gave rise to new aspects that helped reduce dependency on conventional MPPT algorithms and, consequently, enhance the system response, efficiency and cost reduction.

This paper presents a comprehensive exploration of an integrated Buck-Boost converter and Sliding Mode Control (SMC) Maximum Power Point Tracking (MPPT) system for optimizing photovoltaic energy conversion. The study focuses on enhancing solar energy extraction efficiency, regulating output currents, and ensuring effective battery utilization. Through a systematic analysis of converter component sizing and operational modes, the paper delves into the intricacies of the Buck-Boost converter. The unique contribution lies in the innovative integration of SMC with the traditional Perturb and Observe (P&O) algorithm, providing robust and adaptive MPPT under varying environmental conditions. Additionally, the paper introduces a battery management system with three distinct modes, namely, Charging, Direct, and Discharging, offering intelligent control over critical scenarios. Simulation results underscore the robustness of the proposed system under diverse conditions, demonstrating its effectiveness in managing power distribution based on battery charge levels, even in scenarios of insufficient solar power. Overall, this research significantly contributes to advancing the understanding of PV/battery systems and offers a practical, sustainable solution for optimizing energy production, distribution, and storage, marking a substantial stride towards a more efficient and sustainable energy future.

Stability of power converters has always been a major concern when dealing with nonlinear behavior of the system and swarm-based optimization techniques are proven to be handy as they are widely employed. Hence, this study presents an investigative approach to explore the compatibility of applying different variants of Particle Swarm Optimization (PSO) to design an optimized PID controller for DC-DC Buck-Boost converter. This work assesses converter stability through optimization of the PID controller using classical PSO (cPSO), Time-Varying Inertia Weight PSO (TVIW-PSO), Chaotic Descending Inertia Weight PSO (CDIW-PSO), Self-organizing Hierarchical PSO (HPSO) and Random inertia weight PSO (RIW-PSO). The State Space Average (SSA) method is utilized to model and attain the transfer function; eigenvalue analysis and time domain simulation analysis are considered to investigate the stability. Moreover, four objective functions and various performance parameters such as percentage of overshoot, rise time, settling time, and peak amplitude are tabulated to assess the system’s efficiency and the outcomes of different approaches are compared extensively. Amongst all, CDIW-PSO showcased better performances e.g. overshoot of 1.08%, settling time 0.000228s and rise time 0.000143s. The findings illustrate algorithm’s capacity to reduce transient and steady-state faults and makes it compatible with more nonlinear applications. [ABSTRACT FROM AUTHOR]

Summary: Bridgeless ac‐dc converters are the optimal choice for many applications, as they offer many advantages such as low distorted supply current, high power factor, and improved efficiency. This paper presents a new topology for a single‐phase bridgeless ac‐dc converter. The proposed hybrid topology is based on integrating the inverting and non‐inverting buck‐boost dc‐dc converters that are connected to the ac supply through an LC filter. To insure sinusoidal supply current, the proposed hybrid bridgeless ac‐dc converter is operated in discontinuous current mode. The proposed converter has many merits, such as a reduced number of components, enhanced efficiency, and soft start‐up capability. The operation modes and design of the proposed converter are presented. In addition, a design method is proposed for the input LC filter to minimize the voltage stress across switches. Moreover, a small signal model for the proposed converter is developed. The proposed converter topology is simulated to evaluate the dynamic behavior and verify the accuracy of the presented small signal model. Furthermore, an 850 W prototype is developed to validate the features of the proposed converter experimentally. Tight voltage regulation, sinusoidal supply current, and near‐to‐unity power factor operation are observed from the results, regardless of supply or load disturbances. [ABSTRACT FROM AUTHOR]

Power converters are the key link to realize energy transfer from hybrid energy systems (HESs) to loads. In this paper, a family of boost and buck-boost DC-DC converters that is highly desirable for HESs is proposed and analyzed. The proposed converters possess continuous input currents that can realize small input current ripples and avoid the use of large input filters. Besides, the semiconductor counts of the proposed converters are low. Two of the converters employ single-switch double-diode while the other two adopt single-switch triple-diode. The reduced semiconductor counts greatly improve converter efficiency and system reliability. In addition, these boost and buck-boost converters have high voltage-boosting capabilities, and wide voltage gain ranges can be achieved when they are applied to HESs. Theoretical analyses and an experimental prototype are used to verify the characteristics and effectiveness of these converters. [ABSTRACT FROM AUTHOR]

Summary: A coupled inductor based on dual switches buck‐boost converter is proposed in the article, which can be used in renewable energy applications. A wide conversion ratio can be realized by regulating turns ratio of the coupled inductor and the duty cycle. The topology has a quadratic‐like voltage gain, and the low voltage stress and current stress. Combing the passive clamping circuit to recover leakage energy, the voltage spikes of power switches are suppressed, improving the efficiency. Moreover, it has the merits of continuous input current and common ground. To demonstrate the superior performances of the presented converter, the principle of operation and steady‐state analysis are presented in detail. At last, a 100‐W experimental prototype was designed to verify the correctness of the theoretical analysis, with a maximum efficiency of 95.7% in step‐up mode and 96.8% in step‐down mode. [ABSTRACT FROM AUTHOR]

This paper presents modeling and nonlinear control of a two-stage 1-MWh battery energy storage system (BESS) connected to a distribution grid. The BESS is based on a cascaded H-bridge (CHB) multilevel converter offering the distribution of the batteries among multiple submodules which provides safer operation and more flexibility in the voltage design of the batteries. The main function of the BESS is to exchange active and reactive power by controlling the current of the CHB using voltage oriented control strategy. Moreover, this paper proposes a nonlinear state feedback exact linearization controller to control the bidirectional buck–boost converter in each submodule to charge/discharge the batteries and stabilize the dc-link capacitor voltage throughout the operation of the BESS. The proposed controller performance is compared with the conventional PI controller and validated through simulation results. [ABSTRACT FROM AUTHOR]

The buck-boost converter is a non-minimum phase system that presents major challenges in the design of stabilising controllers. A robust nonlinear controller based on the uncertainty and disturbance estimator (UDE) scheme is developed to tightly regulate the output voltage of the converter, subject to unknown input voltage, load resistance, parasitics and parametric uncertainties. A simple procedure is developed that systematically select the controller gains to achieve a satisfactory output response. Using simulation, the effectiveness of the proposed controller is validated and compared to a recent robust nonlinear proportional-integral (PI)-type controller. [ABSTRACT FROM AUTHOR]

This paper presents a new non-isolated high-gain Buck-Boost Converter (BBC) that uses a switched- inductor (SL) voltage multiplier. This type of DC-DC converter can be very useful in renewable energy applications, especially PV, where the output DC voltage is stepped up to a higher voltage. The output voltage of the proposed switched-inductor BBC (SLBBC) is around 15 times the input voltage with positive polarity when a 0.75 duty cycle of the power switches is used. This is achieved without the use of a transformer or common-core coupled inductors, so the topology is simple to construct. This high output voltage is achieved by using the SL voltage multiplier, which consists of three diodes and two inductors. There are two power switches that operate synchronously, which is an advantage of the design. However, it is discovered that the voltage gain in the step-down mode of the proposed converter is less than that of the other converters. The proposed converter is analyzed in the Continuous Conduction Mode (CCM). The operating principles and steady-state analysis are presented in detail. MATLAB/Simulink was used to prove the effectiveness of the proposed SLBBC. [ABSTRACT FROM AUTHOR]