Proposed Converter Topology Research Articles

Design of a triple port integrated topology for grid-integrated EV charging stations for three-way power flow

Environmental fluctuations, solar irradiance, and ambient temperature significantly affect photovoltaic (PV) system output. PV systems should be efficient at the Maximum Power Point in various weather climates to maximize their potential power output. The Maximum Power Point Tracking (MPPT) technique is employed to plan a specific location that yields the maximum amount of power. Operating dispersed alternative energy sources connected to the grid in this situation makes energy control an unavoidable task. This research article suggests designing a power electronics converter topology that links sustainable resources and electric vehicles to the power grid. There are four modes of operation for this proposed converter topology: grid-to-vehicle, vehicle-to-grid, renewable-to-vehicle, and renewable-to-grid discussed. The three power electronic converters and their uses are discussed, and their controllers are also designed to maintain the energy balance and stability in all cases. The battery characteristics indicate the operating mode. The work primarily focuses on the converter’s Triple Port Integrated Topology (TPIT) power flow and voltage control. Here, three power converters integrate the TPIT with three systems-the electric grid, renewable energy, and electric vehicles-into one system. The source battery and solar photovoltaic (PV) array cells are integrated using unidirectional and bidirectional DC-DC converters. The future scope of the work is to investigate the potential of adding additional ports for integrating other energy resources, such as hydrogen fuel cells or additional renewable sources, to create a more versatile and robust energy management system for EV charging stations.

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.

Transformerless High Voltage Gain Y-Source DC–DC Converter with Switched Capacitor for Grid-Connected Photovoltaic Applications

A high voltage gain DC–DC converter with a Y-source network is proposed in this paper for applications such as fuel cells and PV systems. The proposed converter topology is a combination of a Y-source module with a switched capacitor boost module. It is a single switch topology to produce high voltage gain at the load. The superiority of the proposed topology is the high voltage transfer ratio and continuous input current. The voltage gain of the converter can be achieved up to twenty times the input voltage at a duty cycle of 25% itself. The steady state analysis of the converter is carried out using mathematical equations and the working of the converter is explained. The design and analysis of the passive components in the circuit are explained. To illustrate the highlights of the converter, the proposed topology is compared with similar converters in the literature. The simulation of the converter is carried out using MATLAB/SIMULINK. The circuit is verified in the laboratory using a 100[Formula: see text]W prototype.

Designing of self balancing amplitude modulated five level inverter for reducing voltage stress gradients on converter switches for electric vehicles

The research article endeavors to explore the efficient multi-quadrant operations in Electric Vehicles (EV), which emphasizing among the renewable sources and Energy Storage Management Systems (ESMS). This coordination is facilitated through the latest advancements in converter circuits, aiming to enhance efficiency and performance in EV operations. The primary converting circuit, or inverter, is crucial in optimizing the utilization of energy sourced from renewable sources. The coordination among these systems along with the converter, produces harmonics, due to the shifting of operating modes in EV motors in quick sessions because of dynamic real-time road conditions. This research paper presents the design and implementation of Self Balancing Modulated Five-Level Inverter along with a powerful modulation technique and coordinated with the ESMS of electric car application. The proposed 5-Level inverter shows the reduction in torque distortions in an electric vehicle drives over conventional two-stage boost inverter (2SBI) circuits. The designed Five-Level Inverter (FLI) circuit characterized by reduced switching operations, shows a significant reduction in voltage stress gradients on switches and achieves self-balancing of voltages with reduced operating components. The developed three-phase boost single circuit named as SBAM-FLI is connected to the grid integrated renewable energy application and the system is tested at constant and variable torque conditions. A comparative analysis is conducted between the operation of self-balancing modulated FLI with 2SBI based on the obtained results and power loss analysis is performed for the performance evolution in EV applications. The proposed topology is adaptable to both the Trapezoidal and Sinusoidal Back EMF drive mechanisms, which shows significant improvement over conventional inverters. The experimental validation of proposed self-balancing modulated FLI design is presented in this research. The experimental setup was realized using Xilinx block sets and seamlessly integrated with the Basys-3 Artix-FPGA board, consequently, both the experimental and simulation outcomes of the proposed converter topology were validated and provides substantial impact on EV applications.

Improved Topology and Control Strategies for DC Converters in Wind Power Full DC Systems

This study presents an enhanced composite modular DC/DC converter topology designed to address critical technical requirements in wind power full DC systems, including high capacity, high conversion ratio, and fault isolation. The proposed topology combines MMC circuits and module combination circuits, allowing for exceptional modularity and configurability. Through the serial and parallel connection of multiple modules, the voltage or current levels can be further enhanced. Regarding the control strategy, the paper adopts SOGI phase-locked and coordinate transformation technology to precisely measure and control the differential and common-mode voltages within the MMC modules. A mathematical model is established, providing a theoretical foundation for experimental analysis. The research emphasizes the implementation of key strategies such as circulating current suppression, nearest level approximation, and capacitor voltage sorting. To validate the practicality and effectiveness of the proposed converter topology and control strategy, an experiment is conducted using a ±30 kV/±300 kV, 300 MW model constructed within the MATLAB/Simulink simulation environment.

Performance Analysis of a Cascaded Bidirectional DC-DC Converter for High Current Applications

In this paper, a high-current DC-DC converter with bidirectional capability is presented. The proposed converter topology combines a series capacitor bidirectional converter and a conventional bidirectional converter in a cascaded manner, thus achieving a quadratic voltage gain. The proposed topology is compared with other contemporary high current topologies in terms of voltage gains, component count and conversion efficiency. Furthermore, the converter performance is validated using the Simscape SimPowerSystems toolbox of MATLAB Simulink. It is determined that this topology demonstrated a conversion efficiency of 96% and 98% in step-up and step-down mode respectively, for a 250 W load. Moreover, a current gain of 12.5 was observed in step down mode for a switch duty cycle of 0.4. Lastly, current sharing between inductors and low current ripples were also demonstrated.

Investigation of high gain DC/DC converter for solar PV applications

Integration of solar photovoltaic (PV) systems into a microgrid is accomplished with the help of a dual-diode, dual-capacitor, and single-switch DC-DC boost converter. At the output, a power of 400W transfer is achieved together with a voltage gain of 3.92. The converter may be operated in two primary forms, both of that are based on the ON/OFF switches. The benefits that may be noticed in practice from the hardware output are high reliability and decreased switching losses. The properties of the converter are determined via an open loop system that uses pulse width modulation (PWM) switching at 20 kHz. An examination of the step response is carried out. The validations of the proposed converter topology has been compared with the recent converter topologies. The performance of the converter has been evaluated in terms of voltage gain.

A hybrid bridgeless AC‐DC converter topology

SummaryBridgeless 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.

A Hybrid Symmetric Cascaded H-Bridge Multilevel Converter Topology

This paper presents a hybrid symmetric cascaded multilevel converter capable of generating nearly twice the number of output levels as that generated by a conventional symmetric cascaded H-bridge multi-level converter. In the proposed converter topology, each phase comprises one five-level transistor-clamped H-bridge power cell, and the remaining are three-level H-bridge power cells, with all the power cells having equal cell dc-link voltages. Because of the cascade connection of the power cells with equal dc-link voltages, the H-bridge power cells share equal power and is nearly equal to the power shared by the transistor-clamped power cell. The near-equal power sharing condition further helps in effective suppression of the lower-order harmonics present in the input source current waveform if a suitable phase-shifting transformer is employed at the converter input. In this paper, the operating principle and the modulation strategy for the generalized configuration of the proposed topology is explained in detail. The analysis of the capacitor voltages in transistor-clamped H-bridge power cell and converter power loss calculations are also presented. To investigate the performance of the converter system, detailed simulation studies are carried out and the results are validated through experimental results obtained from nine- and thirteen-level laboratory prototypes.

Design of Novel Modified Double-Ended Forward Converter for Stepper Motor Drive

This paper presents the design and analysis of a modified double-ended forward converter (DEFC) for stepper motor-based robotic applications. The proposed converter topology provides galvanic isolation between the input and output while also higher efficiency with a smooth operative system, making it suitable for use in robotic systems that require both power and control signals to be transmitted. The paper also discusses the control strategy for the converter, which uses Proportional Integral (PI) to regulate the output voltage and current. The control strategy is implemented using a microcontroller-based system, which provides precise control of the output parameters. The converter is tested using a stepper motor-based load, and the results demonstrate the effectiveness of the proposed topology and control strategy. In addition to the experimental results, the paper also presents a detailed analysis of the converter’s performance. The analysis includes the input voltage and current, capacitor voltage, MOSFET parameters, output voltage and current, and calculation of efficiency. The analysis results show that the proposed converter topology and control strategy offer high efficiency comparing to existing converting approaches. Overall, the proposed double-ended forward converter offers a suitable solution for stepper motor-based robotic applications, providing efficient and reliable power and control signals. The results demonstrate the effectiveness of the proposed converter topology and control strategy, making it a promising option for use in future robotic systems.

An Adaptive Estimator Based Sliding Mode Control of Nonisolated Single-Input Double-Output Cuk Converter

This article presents an adaptive estimator based sliding mode control (AESMC) for a single-input dual-output (SIDO) converter used in applications requiring multiple regulated output voltages. The proposed SIDO converter is synthesized from the conventional Cuk converter by inserting an additional switch and inductor. However, the coupled capacitor present in the proposed converter topology leads to cross-coupling (CC) and cross-regulation (CR) issues, resulting in the instability of the converter. Furthermore, these issues increase the parameter design and control complexity of the converter. Therefore, this article proposes AESMC to address the CC and CR issues present in the converter. The adaptive estimator of AESMC facilitates the design of adaptive law for effectively estimating the system disturbances. Then, based on the estimated parameters, the input of the SMC is designed to generate switching pulses. Furthermore, the effectiveness of the AESMC in eliminating CC and CR effects is validated by comparing the results obtained with the decoupler+PI controller. Moreover, the system stability analysis with the proposed control technique is presented by considering the Lyapunov direct method. The effectiveness of the proposed control algorithm is evaluated in MATLAB/Simulink, and the obtained results are validated in a hardware prototype developed in the laboratory.

Novel Resonant Power Feedback DC-DC Converter

In this article, a novel soft-switched isolated dc–dc converter topology is proposed that consists of a main power converter using a standard topology, augmented with a resonant power feedback circuit. The power feedback circuit utilizes a fraction of the output power to regulate the input voltage of the main converter. Input voltage regulation proves to be advantageous in applications where wide range of source voltage variations are experienced, such as in photovoltaic microinverters. The operation of main converter with a regulated input voltage results in a near-constant phase-shift angle and a high-frequency current wave shape with a low root mean square value over the entire range of operating conditions. Moreover, the operation with near constant phase-shift angle and the presence of additional resonant current in the feedback circuit extend the range of soft-switched operation of semiconductor devices in the converter. The proposed converter topology and its theoretical analysis is verified through an experimental prototype.

A Highly Reliable Low-Cost Single-Switch Resonant DC–DC Converter With High Gain and Low Component Count

This article presents a novel low-cost, single-switch, high-step-upresonant dc–dc converter with high reliability. The proposed converter topology comprises a low count of components and a simple structure and achieves the low ripple input current characteristic. The inductors in the resonant network participate in the resonant process rather than creating voltage spikes across the switch and likely reverse recovery problems. The circuit operates in the soft-switching condition (ZVS–ZCS conditions in the turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> and turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> transitions), leading to a significant reduction of the switching losses. Moreover, employing film capacitors instead of electrolytic capacitors reduces the size of the circuit and improves reliability. The operational principle and comprehensive steady-state analysis in the continuous conduction mode are discussed in detail, alongside the design considerations of the proposed converter. The validity of the theoretical equations is investigated via experiments, achieving maximum efficiency of 97.69% for a converter designed at the input of 24.5 V, the negative output of 200 V, and the maximum powerof 200 W.

A Novel Design With Condensed Component of Multi-Input High Gain Nonisolated DC–DC Converter for Performance Enhancement in Carbon Neutral Energy Application

This article presents a multiport and multioperating DC–DC converter topology with high step-up output. The proposed converter topology includes two input ports and four switches. Compared to the recently developed topologies, the proposed topology utilizes a minimum number of components and produces high voltage gain. Modularity in shape, simple structure, continuous input, and low input current ripple are the other advantages of the proposed topology. The proposed topology enables bidirectional power flow by interchanging one of the diodes with a switch. Due to flexibility in design, the proposed topology presents a possibility for integrating multiple sources as in a renewable energy conversion system. Smooth switching between the operating modes and reduced voltage stress on switching devices are the other advantages. The working principle of the proposed converter is analyzed thoroughly in steady state. A detailed comparison is carried out considering several performance parameters to show the advantages of the proposed converter. With a proposal to extend the multi-input topology for high voltage boosting application, simulations are carried out for the dual input topology in MATLAB/Simulink platform. The performance of the converter is also validated experimentally on a dSPACE1104 control platform.

Novel Soft-Switched Three-Phase Inverter With Output Current Ripple Cancellation

A novel three-phase dc–ac full-bridge soft-switched inverter topology is proposed in this article that provides an ultralow ripple output current. The proposed circuit utilizes a passive filter that comprises a transformer, an inductor, and a capacitor for achieving soft switching and output current ripple cancellation. Zero-voltage switching (ZVS) is achieved at turn <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> time instant for all the switches in the proposed circuit. The magnitude of ZVS current is optimized throughout the line cycle by the application of the variable frequency modulation technique. In addition to soft switching, an ultralow ripple output current is achieved due to the current ripple cancellation property of the proposed circuit. The output current ripple cancellation is achieved by combining the inverter current with an additional high-frequency ripple current generated by the passive filter. The soft-switched inverter operation and inherent current ripple cancellation achieved by the proposed circuit, result in a high power conversion efficiency. Theoretical analysis and the improvements in inverter performance presented in this article are validated through the experimental verification of the proposed converter topology using a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathbf{600\text{-}W}$</tex-math></inline-formula> lab prototype.

Soft Switched Current Fed Dual Active Bridge Isolated Bidirectional Series Resonant DC-DC Converter for Energy Storage Applications

This paper proposes a high-frequency isolated current-fed dual active bridge bidirectional DC–DC series resonant converter with an inductive filter for energy storage applications, and a steady-state analysis of the converter is carried out. The performance of the proposed converter has been compared with a voltage-fed converter with a capacitive output filter. The proposed converter topology is operated in continuous conduction mode with zero circulation current (ZCC), less current stress and high efficiency. The conditions required for soft switching are determined, and it is found that the converter operates with soft switching of all switches for a wide variation in load and input voltage without loss of duty cycle. Current-fed converters are suitable for low-voltage renewable energy applications because of their inherent boosting capability. An inductive output filter is chosen to make the output current ideal for fast charging and high-power-density battery storage applications. Simple single-phase shift control is used to control the switches. The performance of the converter is studied using PSIM simulation software. These results are confirmed by an experiment on a 135 W converter on an OPAL-RT real-time simulator. The maximum efficiency obtained in simulation is 96.31%. Simulation and theoretical results are given in the comparison table for both forward and reverse modes of operation. A breakdown of the losses of this converter is also presented.

A 9- and 13-Level Switched-Capacitor-Based Multilevel Inverter With Enhanced Self-Balanced Capacitor Voltage Capability

Boost action is required for enhancing the output voltage of the sources such as photovoltaic (PV) sources, fuel cells, and battery storage devices, which eliminates the need for additional units. For this purpose, switched-capacitor (SC)-based multilevel inverters (SC-MLIs) are widely used. The proposed SC-based single-phase MLI is able to produce 13-level output ac voltage and furnishes voltage gains of 3 and 6. The same topology is also able to produce a single-phase nine-level ac output with a voltage gain of 4. The abovementioned voltage levels and voltage gains are achieved using the proposed topology just by modifying the switching strategy used for firing the switches and do not require any modification in the proposed SC-MLI structure. The proposed configuration of single-phase MLI requires less switch count to produce 9- and 13-level ac output voltages with the abovementioned voltage gains. The switches connected in the proposed configuration undergo less voltage stress compared to the MLIs suggested in the literature. The comparison of the proposed converter topology with the existing MLIs reported in the literature is included. The validation of the performance of the proposed inverter is carried out using experimental results captured on a low-power laboratory prototype.

Capacitor Voltage Balancing Control for a Novel 5-Level Dual Active Bridge Converter

Multilevel technology is an attractive solution to increase the cost effectiveness and power density of dc solid state transformers. In this article, a novel five-level (5L) dual active bridge (DAB) converter topology is proposed. By stacking two neutral-point-clamped (NPC) converters at the primary side, the proposed topology could quadruple the input dc-bus voltage of a conventional two-level (2L) DAB converter. Besides, by analyzing the working principle of the 5L-DAB converter, a voltage balancing control method is carried out. With the aid of the voltage balancing method, voltages of the four series-connected dc-bus capacitors in the 5L-DAB converter can be actively balanced, guaranteeing safe operation voltage for all the semiconductor switches. After that, the operation range of the proposed voltage balancing method is derived by theoretical analysis. Finally, the performance of the proposed converter topology and voltage balancing method have been verified by experimental results.

Soft‐switched full‐bridge converter for LED lighting applications with reduced switch current

SummaryLighting systems using light‐emitting diode (LED) have drawn significant attention across the world. This is due to their promising features such as high energy efficiency, reduced greenhouse gas emission, and eco‐friendly nature. However, these systems require constant current regulators to provide constant illumination. This article proposes a soft‐switched full‐bridge LED driver circuit for dc‐grid applications with dimming control operation. The circuit consists of a soft‐switched full‐bridge converter to power different LED lamps with reduced device count from dc‐grid voltage. The semiconductor switches of the full‐bridge converter conduct a small current during on time due to interleaved inductor and equal current sharing of lamp‐2 and lamp‐3. This feature reduces the conduction losses. In addition, the proposed converter yields less component count per lamp, dimming operation through on–off control and zero voltage switching, which results in low switching losses. The detailed steady‐state analysis of the proposed converter for dc‐grid applications with dimming control operation is presented in this work. The performance of the proposed converter is compared with other similar topologies available in the recent literature. Numerical simulations and real‐time experimental validations are conducted to evaluate the steady‐state performance of the proposed converter topology for LED applications, driving multiple lamp loads from dc‐grid. It has been established that the efficiency of the proposed full‐bridge converter is 97.52% at the rated power.

Analysis of an LLC–DAB integrated DC–DC converter topology with low loss and low cost

AbstractThis paper proposes an LLC‐DAB integrated high‐frequency isolated DC–DC converter topology structure to reduce the loss and cost of the DC power distribution system. Furthermore, the complexity and efficiency of the system also can be improved. The proposed converter consists of a DAB converter and two input‐parallel‐output‐parallel half‐bridge LLC resonant converters. It provides two DC voltage level buses, namely the HVDC bus and the LVDC bus. Compared with the typical converter topology of the DC power distribution system, the number of power semiconductors of the proposed converter topology is reduced by sharing the power semiconductors of the DAB converter and LLC resonant converter. As a result, with the number of power semiconductors decreasing, the cost and loss of the system are reduced. Moreover, the proposed converter can control the flow direction of power conversion and supply power to the loads. The single‐phase‐shift modulation method is adopted for the DAB converter, and two LLC resonant converters operate as the DC transformer under resonant frequency with open‐loop control. The operation principles and characteristics of the proposed converter are discussed. Finally, the simulation is carried out and an experimental prototype is developed to verify the effectiveness of the proposed topology.