Multiport Converter Research Articles

Super-Lift Luo-Converter with Integration of Buck Converters for EV Applications

In this work, a super-lift and buck converter (SLBC) are integrated to provide a DC-DC multi-port converter. The single-input dual-output (SIDO) converter under consideration provides benefits over typical positive output voltage superlifting while concurrently producing step-up and step-down voltages using buck and Luo converters. The ripple in output voltages is reduced to a minimum in this construction by generating a dual output without using electromagnetic components. The newly launched SLBC, presently, features simple layout and a reliable control strategy that offers a wide variety of output voltages. Additionally, in order to highlight the benefits of the proposed SIDO converter, a comparison with other equivalent setups is made. Results from simulations and experiments show a significant decrease in conduction losses when compared to other SIDO converters in the similar circumstances. By running a number of simulations in the MATLAB/Simulink programme and putting a 7.5W prototype through testing in the lab, the operating correctness of SLBC is verified

Soft Switched High Step-Up Multi-Port Converter With Single Magnetic Core and Auxiliary Switch for Renewable Energy Applications

Soft Switched High Step-Up Multi-Port Converter With Single Magnetic Core and Auxiliary Switch for Renewable Energy Applications

Multiport converter design and optimal location in distribution grids

Multiport converter design and optimal location in distribution grids

An Isolated Modular Multiport Converter for the Integration of Photovoltaic Energy Sources and Battery Storage in MVDC Networks

An Isolated Modular Multiport Converter for the Integration of Photovoltaic Energy Sources and Battery Storage in MVDC Networks

A Soft-Switched Multiport Converter for Distributed PV Application With Energy Storage

A Soft-Switched Multiport Converter for Distributed PV Application With Energy Storage

Topology synthesis of coupled inductor based four port DC-DC converter for multi-input PV-battery application with autonomous mode selection

Multiport converters are the most reliable and integral component for latest renewable source integration with multiple inputs. This article is one among the kind, which proposes a novel Coupled Inductor based Four Port topology Multiport Converter (CI-FP-MPC) for integrating multiple PV sources with different voltages. The adoption of coupled inductor contributes an increased voltage gain with reduced stress on the switches and diodes. In addition, reduced number of switches and diodes for a four-port topology provides an increase in efficiency due to its reduced switching and conduction losses. Also, soft switching techniques for zero-voltage-switching in switches and zero-current-switching in diodes transfers a smooth commutation between the mode transients and operating intervals. The proposed converter operates with two PV sources with battery as a source and load as well, paving to two modes of operation viz., TISO and DIDO mode respectively. The proposed topology is derived from the conventional high gain boost converter with an add-on of autonomous sensing and control logic to swap and control between the modes. To evaluate and validate its performance, the converter is developed in experimental setup with a power capability of 750 Watts. The control logic and duty cycle adjustments are supervised in Hardware-In-Loop (HIL) arrangement using dSPACE MicroLabBox. The results show increased efficiency, improved voltage gain and robust mode transition during load perturbations.

A design analysis of EV charging using multiport converter and control strategy using MWOA

Recently, there is a massive growth of electric cars and renewable Electric Vehicles (EVs). The hybrid energy sources like Photovoltaic (PV), and battery system is employed for EV system as an input. The energy and battery sources are converted using Multi-port DC-to-DC converter. In this study, we propose a multiport converter-based EV charging system that utilizes both PV and battery sources. The multiport DC-to-DC converter manages the energy flow from these sources to the EVs. The modified whale optimization algorithm (MWOA) is employed to optimize the PWM duty cycle and controller parameters for enhanced performance. A brief modeling of the multiport converter-dependent charging station for EV to integrate power generation of PV, battery energy storage system is employed using MATLAB software. An EV charging control strategy is presented finally. Besides, the switching operation to charge and discharge the battery source are carried based on demand requirements of EV's. The simulation outcomes are estimated and the outcomes of PV and batter power, SOC charging percentage, and EV charging current is projected. Also, the proposed method based on multiport converter system integrated with PV and battery offers enhanced rate of stabilization which includes voltage gain, current ripple, efficiency, switching loss, THD, conduction loss, duty cycle. The outcomes compared reveals that the proposed strategy is offering enhanced outcome than others.

Novel Burst-Mode Control for Medium-to-Light Load Operation of Dual-Active-Bridge Converters, Achieving Minimum Backflow Power, Zero-Voltage-Switching, and DC Bias Suppression

The dual-active-bridge (DAB) converter is widely used in many applications such as solid-state transformers, multi-port converters, and on-board chargers. Nevertheless, its efficiency degrades significantly under light-load conditions due to high switching and conduction losses. Since a detailed analysis for burst-mode design has not been presented in the literature, effective burst-mode control for the light-load condition is proposed in this paper. In the proposed burst-mode, the regular duty cycle and the burst duty cycle are optimally coordinated to achieve the zero-voltage-switching (ZVS) condition and the minimum backflow power at the same time. Moreover, DC bias current is effectively eliminated in the proposed burst-mode. The switching loss and conduction loss are simultaneously minimized in the proposed burst-mode control. Therefore, the light-load efficiency is significantly improved. The detailed analysis and design procedure are also presented for both buck- and boost-mode operations to deal with widely varying output voltage ranges. The control mode switching condition is determined for achieving the ZVS condition for the whole load condition; thus, the proposed burst-mode control flowchart is presented. A 4 kW DAB converter prototype is built to verify the proposed method and the experiment results show about a 2% increment in efficiency of the proposed method compared to the conventional burst-mode method.

Magnetically Integrated Multiport Converter for Energy Management in DC-Powered Buildings

Multiport converters have gained attention in the last few years as a key component for dc-powered buildings, more electric aircraft, and maritime applications. For buildings, the prevalence of dc appliances and electronic loads increases the need for efficient integration with both ac grid and local generation. Ac-dc multiport converters play an important role in this integration because dc distribution has been considered for power integration in modern buildings. In addition, the growing complexity of loads and sources within buildings has driven interest in developing flexible solutions to provide highly efficient integration. Furthermore, ongoing developments in standardization for in-building dc grids underscore the importance of considering specific requirements for future designs. This paper proposes a multiport power converter (ac/dc/dc) to integrate dc-powered buildings into an ac grid. By providing a multiport solution, it is possible to reduce the power processing stages and the component count. To evaluate the effectiveness of this concept, a 5-kW prototype was built and tested, including efficiency evaluation. In addition, emerging standards are discussed to tailor the power converter design for building applications.

Design and performance evaluation of a multi-load and multi-source DC-DC converter for efficient electric vehicle power systems

This paper introduces the design and comprehensive performance evaluation of a novel Multi-Load and Multi-Source DC-DC converter tailored for electric vehicle (EV) power systems. The proposed converter integrates a primary battery power source with a secondary renewable energy source—specifically, solar energy—to enhance overall energy efficiency and reliability in EV applications. Unlike conventional multi-port converters that often suffer from cross-regulation issues and limited scalability, this converter ensures stable power distribution to various EV subsystems, including the motor, air conditioning unit, audio systems, and lighting. A key feature of the design is its ability to independently manage multiple power loads while maintaining isolated outputs, thus eliminating the inductor current imbalance that is common in traditional systems. Experimental validation using a 100 W prototype demonstrated the converter’s ability to deliver stable 24 V and 48 V outputs from a 12 V input, with output voltage deviations kept within ± 1%, significantly improving upon the ± 5% deviations typically seen in existing converters. Furthermore, the system achieved an impressive 93% efficiency under variable load conditions. The modular nature of the converter makes it not only suitable for EV applications but also for a broader range of industries, including renewable energy systems and industrial power supplies. This paper concludes by discussing optimization strategies for future improvements and potential scaling of the technology for commercial use in sustainable energy applications.

Fast Charging System of Electric Vehicle Using Optimized Isolated Multi-Port DC-DC Converter based on Modified Coati Optimization Algorithm

Once clean, renewable energy sources are used to charge the batteries in electric vehicles (EVs), the vehicles can produce zero gas emissions, greatly improving the environment. EVs and other distributed energy storage devices can be used in a smart microgrid to deliver energy to the loads throughout highest times, reducing the impact of load shading and improving the quality of the electricity. To achieve these goals of energy balance between EVs, the grid, and renewable energy sources, an isolated hybrid multiport converter is required. This paper develops an optimized isolated multi-port DC-DC converter for controlling power flow in multiple directions in an EV. This converter contains a dc-dc unidirectional converter, a bidirectional dc-dc converter, a triple active bridge (TAB), and a multi-port dual active bridge converter. Additionally, the Optimal Controller (OC) is developed to manage the power between the EV and the battery. The power flow is achieved by using the Modified Coati Optimization Algorithm (MCOA). In the MCOA, the optimal gain parameter of the converter is selected. In the planned technique, a bidirectional DC-DC converter can be considered to interconnect the EV battery towards deliver bidirectional power flow ability with the battery. The proposed approach is executed in MATLAB, and presentations are assessed by considering performance measures. Moreover, it is contrasted with the traditional approaches of particle swarm optimization (PSO) and grey wolf optimization (GWO).

Modulation strategy design method for single-inductor multi-port converter based on reinforcement learning

Single-inductor multi-port converters have the characteristics of "more silicon and less magnetism" and have great application potential in many fields. However, single-inductor multi-port converters have many switching modes and the modulation strategy design is complex. The current design method is to manually select the switching mode sequence and perform modal analysis. The design process requires power electronics expertise and experience. This paper proposes a modulation strategy design method for single-inductor multi-port converters based on reinforcement learning. This method uses a neural network to generate the modulation strategy and adopts a set of simple rules to provide rewards for training the neural network. Through reinforcement learning, the neural network can summarize experience in trial and error without human intervention and finally generate the optimal modulation strategy. This method has many advantages: (1) It only requires known conditions such as port voltage and converter structure as input, and some simple constraints as rewards, avoiding complicated manual design; (2) It can use a neural network to generate the optimal modulation strategy under different operating conditions, and has strong adaptability. Based on this method, a modulation strategy design for a single-inductor multi-port converter is carried out, and the effectiveness of the method is verified by experiments.

Performance Analysis of a Reconfigurable Fault‐Tolerant Converter for Renewable Energy–Based Standalone System

ABSTRACTThis paper proposes a reconfigurable fault‐tolerant multiport converter for a renewable energy–based standalone system. The operation of the proposed converter for various single and multiple switch faults is discussed and verified with the help of a laboratory prototype. Experimental findings showcase the converter's ability to seamlessly connect renewable sources with a DC bus and an energy storage device, ensuring a consistent, regulated power supply despite single or multiple switch faults. Furthermore, a thorough examination of performance metrics including stress, loss, cost, sensitivity, and reliability affirms the effectiveness and resilience of the proposed approach. Comparative analysis solidifies the notion of the converter's superiority, emphasizing its fault tolerance, efficiency, and reliability when contrasted with alternative solutions.

Research on Decoupling Duty Cycle Optimization Control Method of a Multiport Converter for Dual-Port Direct Drive Wave Power Generation System

Dual-port direct drive wave energy power generation systems (DP-DDWEPGS) have received widespread attention due to their smooth and zero-free output power, compared to single-port direct drive wave energy power generation systems (SP-DDWEPGS) which have the disadvantage of large out-put power fluctuations. To further enhance the performance of the DP-DDWEPGS, optimal power capture control is proposed to achieve maximum power point tracking. Meanwhile, a multiport converter is applied to the DP-DDWEPGS to solve the problem caused by an excessive number of switching devices in the overall system converter. The multiport converter fulfills all the functional requirements of the DP-DDWEPGS while reducing the number of switching devices. However, switch multiplexing of the multiport converter also introduces coupling relationships between each port and the wave force exhibits time-varying characteristics, necessitating advanced control methods with superior fast-tracking capability. Therefore, in this paper, a decoupling duty cycle optimization model predictive control for DP-DDWEPGS is proposed. Based on the characteristics of switching multiplexing, NSC finite control set model predictive control (FCS-MPC) decouples the current prediction and the cost function, reduces the number of candidate voltage vectors in each operation, and shortens the operation time by 70%. To address the issues of high ripple value and increased error due to decoupling in FCS-MPC, duty cycle optimization control is added, greatly reducing the fluctuations in electromagnetic force and power of the permanent magnet linear generator (PMLG). Based on the established simulation model, the feasibility and superiority of the multiport converter and decoupling duty cycle optimization model predictive current control method are verified.

State of-The-Art Multi-Input DC-DC Converter Topologies and their Control Techniques: A Review

Environmental awareness and technological advancement have made renewable energy sources such as fuel cell,solar photovoltaic (PV), wind energy an emerging research area. Power electronics converters are used as interface betweenthe renewable energy sources and the load unit, aimed at matching these sources with the load demand and improving thesteady-state and dynamic characteristics. Traditional method of using multiple single-input single-output dc-dc converter tointegrate several renewable energy sources, comes with challenges in controller design, poor efficiency, low power densityand increase in cost. To address these limitations, the use of an integrated multi-port converter is a preferable solution.Recently, several multi-port dc-dc converter topologies have been reported each having its peculiarity in terms of number ofcomponent count, relationships between input and output, voltage conversion ratio, control algorithm and efficiency. Thisarticle reviewed multi-port dc-dc converters presented by different research groups from the point of view of topology, inputand output relation and structure. Furthermore, control algorithms proposed to solve various control problems are alsoreviewed.

Power Capability Domain Analysis for M2DC-Based AC/DC/DC Multi-Port Converter

Power Capability Domain Analysis for M2DC-Based AC/DC/DC Multi-Port Converter

Empirical design and comprehensive analysis of multiport converter in distributed generation enabled microgrids

Distributed generation-enabled microgrids are a revolutionary approach for the energy paradigms that will transform the ways of generation, distribution, and utilization. A decentralized approach to energy generation in microgrids results in the robustness and independence of energy networks. Empowerment of the communities to take control of energy requirements with multiport converter-based microgrids promotes sustainability, efficiency, reduced losses, and increased resilience against the evolving trends of the energy sector. In this research, a hybrid energy-integrated multiport converter is designed and analyzed under its various modes of operation. Rapid transitions from one energy source to another are attained within 0.4μs to feed the load at a steady state voltage of 400 V, and within 0.15μs to charge the energy storage system at a steady state voltage of 48 V which indicates the robustness and independence of energy systems via this proposed approach. The resilience of the microgrid is obtained because of this rapid trans Moreover, the proposed converter offers a voltage gain of 8.3 with 96 % efficiency making it sustainable for maximization of renewable energy. In addition, the resilience of the proposed converter is exhibited through high power densities at power losses of not more than 7.5 % making it an innovative candidate for hybrid energy systems as compared to existing technologies. Simulation scenarios are validated through mathematical analysis, proving their effectiveness in distributed generation-enabled microgrids. The proposed research model is effective in a real environment because of the minimal effects of parasitic resistance, reduced total harmonic distortion under different loads, and negligible electromagnetic interferences, demonstrated through simulations.

Modeling and control of a new multi-port converter for hybrid energy system integration

This research introduces a new topology called the quasi-Z-source integrated isolated multiport bidirectional resonant DC-DC converter. The aim is to achieve cost-effective and efficient multi-directional power flow between photovoltaic (PV), battery/supercapacitor, and DC loads. The proposed topology ensures uninterrupted power supply to the loads and supports reverse power transfer through its bidirectional power flow capability. By combining quasi z-source and H-bridge resonant converters with an existing switch, a four-port converter is achieved without the need for separate converters or additional switches. The high-gain quasi z-source converter reduces the required voltage ratings of the battery and supercapacitor packs while enabling the utilization of a high-frequency transformer (HFT) with a low turns ratio. Isolation between the ports is achieved using a secondary center-tapped HFT equipped with a controlled full-wave rectifier on the secondary side, allowing bidirectional power flow. A power flow management system and corresponding control scheme are proposed to optimize the system's performance. The proposed system's performance is evaluated under various operating conditions, demonstrating its effectiveness in power flow management and overall efficiency. The results confirm the feasibility and effectiveness of the proposed system.

An embedded inductor current estimation system for integrated multiport converter in hardware-in-the-loop applications

Multiport power electronics converters enable interfacing of multiple sources and loads within a renewable-rich dc microgrid. The system evaluation of these microgrids such as dynamic performance of components, stability analysis are often evaluated using hardware-in-loop (HIL) approach for different real time conditions. The digital twin of device under test (DUT) is realized within real time simulator using voltage and current sensor measurements in the HIL-based testing approach. Current sensing systems for multiport power converter systems require transducers to be connected in path of current with restrictions on sensor bandwidth, auxiliary circuit overhead requirements for biasing and signal conditioning. This paper addresses the development of high frequency current sensing method using shunt-type measurements with reduced auxiliary circuit overheads. The proposed method provides a digital estimate of inductor current which can be implemented in an embedded processor.

Enhancing DC microgrids integration with three-phase AC grids using multiport converters

Enhancing DC microgrids integration with three-phase AC grids using multiport converters