Output Voltage Ripple Research Articles

A non-isolated converter of switching current stress in DC-DC converter for integrating PV and battery storage system

ABSTRACT High-gain DC-DC converters have seen significant adoption in renewable energy systems like Photovoltaic (PV), Fuel Cells (FC), and other systems. However, their effectiveness is increasingly tied to the availability of renewable resources. As Renewable Energy Sources (RES) typically generate electricity at low voltage levels, integrating high-gain DC-DC converters with RES is crucial for optimal performance. This paper introduces an innovative DC-DC converter design that achieves high gain and is specifically able to integrate smoothly with RES like PV systems and battery storage. The innovation of the proposed converter lies in its integration of conventional boost and buck-boost converters, enabling a high voltage gain while minimizing output voltage ripple and reducing switch current stress. Additionally, its unidirectional power transfer port allows efficient energy flow from solar PV or battery sources to the load, making it highly adaptable for managing fluctuating energy sources, a feature that distinguishes it from current modern converters. Its design simplifies architecture by combining traditional converter types, reducing the number of components, which leads to cost savings, lower weight, and improved reliability. Additionally, the design minimizes output voltage ripple and reduces switching current stress, enhancing the converter’s durability under variable operating conditions. The converter’s performance is evaluated through simulation and experimental studies, demonstrating a 96.3% efficiency and 5.5 times of voltage gain. The converter’s feasibility and effectiveness are validated under dynamic scenarios with varying solar irradiation, making it an ideal solution for clean energy generation systems, including hybrid energy generation setups. The proposed converter topology offers an auspicious solution for high-gain DC-DC conversion in renewable energy systems.

Output Voltage Ripple Suppression of PPSS-LCC Converter for Medical X-Ray Application Based on Repetitive Control

Output Voltage Ripple Suppression of <i>PPSS</i>-<i>LCC</i> Converter for Medical X-Ray Application Based on Repetitive Control

Conducted interference and voltage ripple suppression study in LLC resonant converter based on symmetric chaotic spread spectrum

ABSTRACT Spread-spectrum modulation technique can effectively reduce the peak value of conducted interference in automotive LLC DC/DC converters, but it will bring more serious ripple problems to Class E resonant converters. In this paper, we investigate the voltage ripple trend of LLC resonant converter when applying spread-spectrum modulation, and propose a chaotic signal sampling rule under the minimum output voltage ripple. A symmetric chaotic spreading method is proposed to reduce the output voltage ripple from the source by changing the distribution sequence of the chaotic signal to make it centrosymmetric. The symmetric chaotic spread spectrum is simulated and analysed to be able to suppress the conduction interference while reducing the voltage ripple, and is verified by experiments. This modulation strategy does not require the addition of auxiliary circuits and additional control links, which saves cost and reduces the difficulty of designing control links.

DEVELOPMENT OF DUAL-SWITCHES BRIDGELESS PFC TOTEM-POLE SEPIC CONVERTER FOR LED DRIVER APPLICATION

This paper presents a Dual-Switch Bridgeless Power Factor Correction (DSBPFC) Single Ended Primary Inductor Converter (SEPIC) with Totem-Pole circuit structure for LED Driver Application. The conventional Full-Bridge Rectifier (FBR) SEPIC converter has five diodes, four in the rectifier bridge and one in the SEPIC. In addition, the FBR SEPIC converter has several drawbacks, including low power factor (PF), high current harmonics (THDi), and high output voltage ripple, due to the combination of two operation circuits in a single converter structure. The proposed DSBPFC SEPIC converter with Totem-Pole method improves PF and reduces THDi and output voltage ripple compared to the conventional FBR SEPIC. Additionally, it only requires three diodes instead of five. The optimization parameter design minimizes the THDi and output voltage ripple. In addition, to improve the quality of the AC source, the inductors are designed to operate in DCM and CCM based on the ripple-balancing concept between input and output inductors. As to reduce output voltage ripple, a high capacitance of output capacitor is used. The simulation result of the THDi is 3.8% whereas the experimental result shows that the THDi is 23.5%; which can be attributed to the parasitic elements at the passive components. Furthermore, the experimental results of the output voltage ripple are 2 V with output capacitance of 3300 μF, compared to the output voltage ripple of 4.40 V for 470 μF. Therefore, the proposed converter's design is confirmed with an output power of approximately 14.4 W.

A new positive output DC–DC buck–boost converter based on modified boost and ZETA converters

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.

A modified fractional short circuit current MPPT and multicellular converter for improving power quality and efficiency in PV chain.

This article presents the contribution of multicellular converters in improving of the quality of power produced in photovoltaic chain, with the aim of exploiting the maximum power produced by the photovoltaic generator with low oscillations around of the maximum power point (MPP) at steady state and to reduce switching losses. After modeling the multicellular parallel boost converter, fractional short circuit current (FSCC) MPPT was modified to get an estimated photocurrent as a reference to control the inductance current for good functioning of the converter in pursuit of the maximum power point. To verify the performance of the proposed solution, the system was submitted to irradiance and temperature variations. The simulations carried out in the Matlab/Simulink environment presented satisfactory results of the proposed solution, in comparison with the high-gain quadratic boost converter we have a response time of 0.04 s, power oscillations at maximum point around 0.05 W and efficiency of 99.08%; in comparison with the interleaved high-gain boost converter the results show a response time of 0.1 s for the transferred power, a very low output voltage ripples of 0.001% and 98.37% as efficiency of the chain. The proposed solution can be connected to a grid with a reduction of level of the inverter and active filter.

Energy-efficient Vienna rectifier for electric vehicle battery charging stations

Global DC fast-charging infrastructure is being rapidly developed to accommodate the ever-increasing demand from the electric vehicle market. A major complication in the electric power system's process is the proliferation of ultra-fast charging (UFC) stations, which are known for their enormous power consumption and unpredictable, intermittent performance. By implementing grid-supportive features and ensuring an improved power consumption profile for the grid, installing regional energy storage can solve these challenges. This study presents a control approach for managing the grid-side AC/DC converters of rapid charging stations focused on future-oriented regulation. The paper primarily concentrates on various Vienna rectifier topologies. The technology, characteristics, benefits, and operational aspects of Vienna rectifier topologies are vital to improving the performance, efficiency, and grid integration of electric vehicle charging systems. Fast charging, grid stability, energy economy, and the smooth integration of electric vehicles into the electrical grid are all made possible by Vienna rectifiers. When used in battery energy storage systems (BESS) for electric vehicle charging infrastructure, Vienna rectifiers allow for effective discharge and charging of the batteries. The configurations and assessments of these converters are examined, assessed, and compared based on power output parameters, element count, power factor, THD, and efficiency. The Vienna rectifier has been identified as the best suitable DC fast-charging converter architecture for power levels exceeding 15 kW due to its exceptional efficiency, limited output voltage ripples, high power density, reduced current ripples, and reliable performance. Research on ways to improve electric vehicle charging infrastructure can be spurred by a better grasp of the Vienna rectifier's technological complexities and performance benefits, leading to greener and more efficient transportation options. As a result, the system's power density will eventually rise and elemental stress will decrease.

Design of a Portable Emergency DC Power Supply

Abstract In recent years, wireless or handheld devices have become increasingly widely used, especially in areas such as environmental monitoring and the Internet of Things. However, due to environmental conditions, they cannot rely on the power grid to provide electricity, and energy supply has become a key issue that restricts the deployment and operation of such devices. This article introduces the method and principle of applying a microcontroller control system to a portable emergency DC power supply, and proposes a method for a portable emergency DC power supply with adjustable and stable output. The output voltage can be adjusted in steps of 0.1-15V. This adjustable portable emergency DC power supply not only has the advantages of small volume and low loss of switch mode power supply, but also has the advantages of small output voltage ripple and good output characteristics of linear power supply. It has certain research significance and practical value.

A Novel Second Harmonic Voltage Suppression Control for PSFB Converter in Dual-Stage Single-Phase Rectifier

The inherent second harmonic power pulse in single-phase grid-connected rectifiers leads to a noticeable output voltage ripple and thus results in the degradation of the system. A novel second harmonic suppression control is introduced in this paper to address this issue. The key point of the proposed control lies in the real-time prediction of the phase-shifted full-bridge (PSFB) converter’s desired duty cycle through accurate PSFB converter modeling. By accurately predicting the ideal duty cycle, the proposed control facilitates a significant enhancement in the control loop’s gain specifically at the second harmonic frequency, thereby improving the overall system performance. To validate the theoretical analysis, a series of simulations and experiments were conducted. The results demonstrate the effectiveness of the proposed second harmonic suppression control in mitigating second harmonic output voltage ripple.

Composite Duty Modulation of Dual Active Bridge Converters to Minimize Output Voltage Ripples and Inductor RMS Currents

Composite Duty Modulation of Dual Active Bridge Converters to Minimize Output Voltage Ripples and Inductor RMS Currents

Commutation strategy for reduced output voltage ripple in alternative cascaded boost converter

SummaryWith the rapid penetration of low‐voltage direct current (DC) generators such as photovoltaic panels and storage energy systems, the need for processing energy has propitiated the optimization of power electronics converters. Conventional topologies of power electronics converters have well‐known limitations, mainly due to the parasitic elements and finite commutation times, which do not allow for obtaining a sufficient voltage gain. The literature review has demonstrated that cascade topologies are suited to overcome these limitations. However, to provide a low‐ripple output voltage, they require high values of capacitances. This paper presents an alternative boost converter developed by cascading two power cells. The conventional configuration is slightly modified, producing an alternative power cell. Even though the number of elements is increased, following the suggested commutation strategy, the derived converter can substantially reduce the output voltage ripple. Therefore, capacitors of small value can be employed, avoiding using electrolytic capacitors with shorter life spans than their film counterparts. Besides, given the cascaded connection, the converter possesses a quadratic‐type gain since two independent commanding signals are applied. The different states of commutation are analyzed in depth, allowing the selection of an adequate commutation strategy, which gives the advantage of canceling the output voltage ripple. The mathematical model of the converter is presented and then validated via a scale‐lab prototype. The simulation results evidence the good dynamic performance of the control‐loop design by means of the frequency response analysis.

Minimizing Voltage Ripple of a DC Microgrid via a Particle-Swarm-Optimization-Based Fuzzy Controller

DC microgrids play a crucial role in both industrial and residential applications. This study focuses on minimizing output voltage ripple in a DC microgrid, including power supply resources, a stochastic load, a ballast load, and a stabilizer. The solar cell serves as the power supply, and the stochastic load represents customer demand, whereas the ballast load includes a load to safeguard the boost circuits against the overvoltage in no-load periods. The stabilizer integrates components such as electrical vehicle batteries for energy storage and controlling long-time ripples, supercapacitors for controlling transient ripples, and an over-voltage discharge mechanism to prevent overcharging in the storage. To optimize the charging and discharging for batteries and supercapacitors, a multi-objective cost function is defined, consisting of two parts—one for ripple minimization and the other for reducing battery usage. The battery charge and discharge are considered in the objective function to limit its usage during transient periods, providing a mechanism to rely on the supercapacitor and protect the battery. Particle swarm optimization is employed to fine-tune the fuzzy membership function. Various operational scenarios are designed to showcase the DC microgrid’s functionality under different conditions, including scenarios where production exceeds and falls below consumption. The study demonstrates the improved performance and efficiency achieved by integrating a PSO-based fuzzy controller to minimize voltage ripple in a DC microgrid and reduce battery wear. Results indicate a 42% enhancement in the integral of absolute error of battery current with our proposed PSO-based fuzzy controller compared to a conventional fuzzy controller and a 78% improvement compared to a PI controller. This translates to a respective reduction in battery activity by 42% and 78%.

Designing an optimal PID controller for a PV-connected Zeta converter using genetic algorithm

This paper suggests a way of fixing problems of voltage fluctuations and peak overshoot in a PV-connected Zeta converter system. The Zeta converter in the proposed approach is controlled using proportional integral derivative (PID) while a genetic algorithm (GA) calculates the PID coefficients based on the control mechanism. The performance of the designed system was analyzed in a MATLAB/Simulink environment. The analysis showed that the proposed system reduced the output voltage ripple and peak overshoot during transient conditions by providing feedback to the converter through the PID controller, this is a significant improvement when compared to the results found without a PID controller.

High-Performance Light Emitting Diode Lighting Circuits and Their Interior Design Applications

This study explores the application of the half-bridge Inductor-Inductor-Capacitor (LLC) resonant converter in Light Emitting Diode (LED) lighting driver power supplies, with a specific focus on improving efficiency and dimming capabilities. The investigation begins with an analysis of the sliding mode control (SMC) method, utilizing a constant-current design with a fixed switching frequency (FWF). A novel fuzzy frequency-selective SMC dimming strategy is proposed to recognize the challenge of significant output voltage ripple during dimming under a FSF. To address the ripple issue during dimming, an electromagnetic filtering circuit is designed, and a zero-voltage turn-on Metal—Oxide—Semiconductor (MOS) tube is introduced, incorporating a synchronous rectification scheme to mitigate losses in the secondary-side rectification diode. The study comprehensively considers a current-mode self-driven method, specifically tailored to the LLC circuit’s different operating modes. The LLC resonant circuit, along with the subsequent synchronous rectification circuit, is meticulously designed for a 252 W LED driver power supply prototype. A closed-loop simulation circuit model is developed using PSIM software in experimental validation. The feasibility of SMC based on a FSF is affirmed through a comparative analysis of SMC signal waveforms, steady-state output current (OC) models, and resonant tank current waveforms. The investigation into the OC under various SMC conditions demonstrates the half-bridge LLC resonant converter’s ability to achieve stable output with minimal ripple. The designed LED lighting circuit is applied to indoor design, providing adjustable LED brightness and switch status at different power levels. Although obstacles slightly impact the communication quality of the circuit, it remains suitable for the majority of users’ needs.

Ripple analyze and design considerations for an interleaved boost converter (IBC) for a PV source

This paper approaches the interleaved boost converter (IBC) for photovoltaic systems (PVS) with efficiency control. The purpose of this converter is to transfer the low DC PV voltage to a high DC voltage at its output. The low output voltage ripple and especially the low input current ripple (for MPPT) are analyzed, verified and compared to N cell IBCs. To improve the efficiency of the IBC, the control decides how many commutation cells are used, in relation to the actual power. This paper also shows to determine the critical PV current needed to work in continuous conduction mode. Finally, a dual IBC is experimental tested to verify the theoretically approaches.

Model Predictive Virtual Flux Control Method for Low Switching Loss Performance in Three-Phase AC/DC Pulse-width-Modulated Converters

Three-phase AC/DC pulse-width-modulated (PWM) converters have been widely employed in various renewable energy systems and industrial applications, which require a high-efficiency power converter operation. This article proposes a technique to reduce switching loss in AC/DC converters by integrating a voltage vector preselection strategy to model predictive virtual flux control. The voltage vector preselection strategy preselects available voltage vectors corresponding to switching states that lead to minimum switching loss in the phase leg, which conducts the highest current. By using preselected voltage vectors, clamping intervals are generated at every fundamental period to maintain the present switching states of the power switches, resulting in the reduction in switching loss. Additionally, by using virtual flux control, the proposed approach can effectively be used under both ideal and distorted source voltage conditions. The proposed method is compared with the conventional model predictive current control and the conventional model predictive virtual flux control. Both a simulation and experiment are performed to validate the correctness and effectiveness of the proposed method, which has been found to decrease the switching loss of an AC/DC converter by up to 15% compared to conventional control schemes at a negligible increase in the input current total harmonic distortion and DC output voltage ripple.

Modeling and simulation analysis of interleaved double dual boost converters in energy storage field

AbstractAlthough interleaved double dual boost converters have been widely studied for energy storage, their detailed feature analysis is rarely discussed. To this end, this paper systematically analyzes features regarding interleaved double dual boost converters to provide the basis of the controller design. First, the topological structure and working principle are introduced, which is an indispensable pretreatment for the steady‐state feature analysis. Second, the voltage gain analysis, and input voltage ripple analysis output voltage ripple analysis, which is an indispensable feature analysis for the following controller design. Furthermore, the relative controller regarding the interleaved double dual boost converter is proposed in this paper. Finally, the simulation and experimental results illustrate the effectiveness of the feature analysis.

Dead-Time Effect in Inverters on Wireless Power Transfer

This paper presents a comprehensive analysis of the dead-time effects in wireless power transfer systems based on LCC-S topology. In these systems operating at high frequencies, the ratio of dead-time versus the operating period becomes critical, and the dead-time issue can cause certain problems regarding power quality, efficiency, and output voltage ripple. The impact of input quantities such as voltage and switching frequency on the efficiency and output power of the LCC-S-tuned WPT system was also investigated. The optimal combination of these parameters used to achieve the maximum efficiency for a target output power and to set the appropriate value of the dead time were determined by running multiple simulations using the MATLAB R2023b software platform. It was also shown that the output voltage remained unchanged with and without a load and up to 1200 ns of dead-time, which provides a simple implementation of the corresponding mathematical model. In the recommended interval of 600–1500 ns, the influence of the dead-time on the value of the output voltage amplitude is less than 10%. The validity of the proposed method was confirmed through the implementation of the experimental prototype, a 5 kW wireless power transmission system, and the obtained results were in accordance with the simulation results.

Design and Analysis of a Three-Phase Interleaved DC-DC Boost Converter with an Energy Storage System for a PV System

This paper describes a groundbreaking design of a three-phase interleaved boost converter for PV systems, leveraging parallel-connected conventional boost converters to reduce input current and output voltage ripple while improving the dynamic performance. A distinctive feature of this study is the direct connection of a Li-Ion battery to the DC link, which eliminates the need for an additional charging circuit, which is a departure from conventional approaches. Furthermore, the combination of an MPPT controller and a closed-loop fuzzy controller with a current control mode ensures accurate switching signal generation for all three phases. The meticulously tuned system exhibits a remarkably low ripple content in the output voltage, surpassing calculated values, and demonstrates a superior dynamic performance. The investigation extends to a comprehensive analysis of losses, encompassing inductor copper loss and semiconductor conduction loss. In all scenarios, the converter exhibits an efficiency exceeding 93%, highlighting its robust performance as an effective solution for PV systems.

A Transformerless Photovoltaic System Employing a Cubic Cell Boost Converter for Low Voltage Application

A photovoltaic (PV) system is commonly used to satisfy the power demand of the utility. This paper investigates the utilization of a high voltage gain Cubic Cell Boost Converter (CCBC) in a transformerless photovoltaic (PV) system for low voltage applications. The proposed system is a combination of a CCBC and a three-phase inverter creating a two-stage three-phase PV system. The CCBC is linked with the low-scale PV sources to step up its input DC voltage and maintain a constant DC bus voltage by employing the Perturb and Observe (P&amp;O) Maximum Power Point Tracking (MPPT) control algorithm. The DC bus is further connected to an LCL filter based three-phase inverter using a synchronous reference frame (dq) control scheme to power the three-phase utility. The proposed combination is validated by simulating in MATLAB/ SIMULINK environment for a 5.5 kW PV source and achieved an efficiency of 91% with 1.91% of inverter Total Harmonic Distortion (THD) at unity power factor. In the proposed system, CCBC with P&amp;O MPPT control provides a high step-up DC bus voltage with less input current ripple and output voltage ripple and maintains a constant DC bus under variable solar irradiance. This work does not account for the common leakage current that is often produced in a transformerless PV system.