Power Electronics Research Articles

High-power three-phase interleaved parallel NPC structure DC-DC converter modeling and simulation

Abstract In fields such as DC microgrids, renewable energy generation, and electric vehicle charging stations, three-phase NPC structure DC-DC converters play an irreplaceable role, constituting a significant part of modern power electronics technology. Mathematical models are established based on various operating modes of IGBT switching devices under PWM control, encompassing input voltage, output voltage, phase currents, average current, and duty cycle. Simulation models are constructed on the MATLAB platform to confirm the correctness of these mathematical models. Closed-loop control strategies are implemented using proportional-integral (PI) controllers. This control strategy serves to confirm the precision of the mathematical models.

Analysis of the resonant converter for multi-terminal collection of DC offshore wind farms

Abstract With the rapid development of power electronics technology, the offshore wind power system using DC collection and DC transmission is the best solution to increasing offshore distance. Resonant converters achieving soft switching have become a common choice in the DC/DC power conversion system. This paper proposed a design scheme for the multi-terminal collection of DC offshore wind farms based on the resonant converter. The operating principles are analyzed, and variable-frequency control of the converter is utilized to control the output voltage. Simulation verifies the effectiveness of the multi-terminal DC collection system and its control strategy.

Black-Box Modelling of Active Distribution Network Devices Based on Neural ODEs

Abstract The morphological structure and dynamic characteristics of power distribution systems are rapidly evolving due to the widespread application of distributed renewable energy and the rapid advancement of power electronics technology. The stability analysis of these complex new distribution systems depends on electromagnetic transient (EMT) simulation. However, the intellectual property rights protection by manufacturers leads to many distribution network devices that can only use black-box models with missing parameters, which challenges the simulation. This reduces the accuracy of the dynamic analysis of these new distribution systems. To address this problem, this paper proposes a black-box modelling method based on neural Ordinary Differential Equation (ODE) for active distribution equipment. The method uses port measurement data to construct a data-driven model that accurately captures the black-box device characteristics, transforming the uncertainties in the user-side black-box devices into observable, controllable, and analysable models. The paper also builds an IEEE-33 node system that includes the energy storage black-box model for validation, and the results confirm the accuracy of the model.

Study and Modeling of the Electromagnetic Radiation Sources Based on Phaseless of Near Magnetic Fields for Power Electronics Applications

Study and Modeling of the Electromagnetic Radiation Sources Based on Phaseless of Near Magnetic Fields for Power Electronics Applications

Conference Report: International Conference on Integrated Power Electronics Systems, CIPS 2024 March 12-14, 2024, Düsseldorf, Germany

Conference Report: International Conference on Integrated Power Electronics Systems, CIPS 2024 March 12-14, 2024, Düsseldorf, Germany

Traversal-based automatic EMT modeling approach for new type of power systems with massive power electronics

Traversal-based automatic EMT modeling approach for new type of power systems with massive power electronics

Laser Speckle Photometry for Inline Defect Detection in Solder Connections of Power Electronics

Zusammenfassung Bei der Herstellung von Leistungselektronik ist die Qualität und Zuverlässigkeit ein wichtiger Faktor. Vor allem die Verbindungsschicht zwischen dem Chip und dem keramischen Substrat weist häufig Defekte auf, die die Wärmeableitung in diesen Bereichen verringern können. Dies kann zu einer Überhitzung führen und die Lebensdauer des Bauteils verringern. Im schlimmsten Fall können solche Fehler große Auswirkungen auf sicherheitsrelevante Systeme haben. Daher ist eine Qualitätskontrolle innerhalb der Produktionslinie bzw. vor der Verpackung der Bauteile sehr wichtig. Die Laser-Speckle- Photometrie (LSP) bietet eine vielversprechende Lösung für dieses Problem. Speckle-Muster werden durch interferierende Lichtwellen erzeugt, die von der beleuchteten Oberfläche reflektiert werden. Das Verhalten dieser Muster ist eng mit dem Oberflächenzustand der untersuchten Proben verbunden. In diesem Beitrag wird ein auf der LSP basierendes Qualitätskontrollkonzept für den Produktionsprozess von Leistungselektronik-Chips für die Automobilindustrie vorgestellt. Ziel ist es, die Hohlräume in der Lötverbindung zu finden und zu bewerten und darüber hinaus die Porosität in gesinterten Verbindungen zu bestimmen. Insbesondere die Größe und Lage dieser Hohlräume sind von großem Interesse. Erste Untersuchungen haben vielversprechende Ergebnisse gezeigt und Defekte mit einer Größe von weniger als 15 % (v/v) der eigentlichen Verbindungsschicht gefunden. Dies beweist, dass die LSP ein vielversprechender Ansatz zur Überprüfung der Verbindungsqualität von Chips bei der Herstellung von Leistungselektronik ist.

IEEE Journal of Emerging and Selected Topics in Power Electronics Publication Information

IEEE Journal of Emerging and Selected Topics in Power Electronics Publication Information

Heat transfer characteristic of an alumina oscillating heat pipe

Oscillating heat pipes (OHP) are a promising and highly efficient heat transfer technology especially in the field of power electronics thermal management. However, conventional metal OHP do not meet the need for insulation or low coefficients of thermal expansion. In order to expand the application field and break the application limitation of the OHP technology, alumina ceramic oscillating heat pipes was designed and investigated in this paper. The alumina OHPs combine the excellent insulating, oxidation-resistant, corrosion-resistant and low thermal expansion properties of alumina ceramic with the efficient heat exchange mechanism of oscillating heat pipe technology, exhibiting great application potential. An alumina flat-plate oscillating heat pipe was prepared, 6 internal microchannels were examined using micro-CT, and the microstructure was characterized using scanning electron microscopy. The heat transfer characteristics of the OHP charged with water were investigated using a heat transfer test system. Increasing heat loads were employed to the OHP, and the operating temperature of 20 °C and 60 °C as well as the orientation varied between 0° and 90° were also introduced. The oscillation motion of the alumina OHPs were investigated, including temperature oscillations before and after startup of the OHPs, and a comparison effective thermal conductivities at various tilt angles and operating temperatures was carried out. The experimental results revealed that the heat transfer performance of the alumina oscillating heat pipe significantly increased with the increased heat loads and reached to 861.7 W/(m∙K) at 56 W. The effective thermal conductivity of the OHP was 6 times higher than that of the empty OHP at heat load of 16 W. When the orientation was 30°, the temperature oscillation instability increased, the oscillation amplitude increased, and the heat transfer performance of the oscillating heat pipe decreased. As the operating temperature increased, the stability of temperature oscillations improved, the amplitude decreased, and heat transfer performance was enhanced.

Active balancing system in battery management system for Lithium-ion battery

The existing battery management systems perform many functions, such as simply monitoring the battery's voltage, current, and temperature for the most basic and compensating energy imbalances between battery cells for the most advanced systems. In this last example, the function balancing helps protect the battery from obtaining a better lifespan. However, these systems with such functions remain complex because they involve techniques specific to power electronics and energy conversion. The number of components, implementation complexity, and cost increased. The work presented in this paper fits directly into this context. The main objective is to provide a solution to the problem of battery management and careful pack cell balancing. The proposed system aims to balance the battery pack cells based on the intermediate state of charge by charging or discharging the imbalanced cell. The implementation of the proposed control strategy was for a battery pack composed of five cells under MATLAB/Simulink.

High energy storage performance in BTO-based ferroelectric films

Dielectric capacitors play an increasingly important role in modern electronic power systems due to their ultrahigh charging and discharging speeds and power density. Much research has focused on enhancing dielectric breakdown strength to achieve better energy storage performance; however, this increases the potential for heat generation and unexpected insulation failures, thereby affecting the stability and lifespan of devices. This study introduces a small amount of Na+ dopants at the A-site of BaTiO3, inducing lattice distortions and enhancing local polarization to increase energy storage density rather than through enhancing breakdown strength. The introduction of Na+ enhances the ferroelectric properties, with polar nano-regions (PNRs) gradually evolving into long-range ordered large domains. In the Ba0.985Na0.015TiO3 films, the coexistence and coupling of abundant PNRs with a few long-range ordered ferroelectric domains result in high saturation polarization and low residual polarization. At a moderate electric field of 2.3 MV cm−1, an ultrahigh energy density of 44.3 J cm−3 and a high energy storage efficiency of 78.6 % were obtained. Additionally, the film exhibits excellent frequency stability (100 Hz-20 kHz), temperature stability (30–180 °C), fatigue resistance (107 cycles), and high pulsed discharge energy density, along with great thermal stability. This work provides new insights into achieving exceptional energy storage performance in single-phase films.

Heating mode transitions in capacitively coupled CF4 plasmas at low pressure

Abstract Capacitively coupled plasmas operated in CF4 at low pressure are frequently used for dielectric plasma etching. For such applications the generation of different ion and neutral radical species by energy dependent electron impact ionization and dissociation of the neutral background gas is important. These processes are largely determined by the space and time dependent electron energy distribution function and, thus, by the electron power absorption dynamics. In this work and based on a particle-in-cell/Monte Carlo collision model, we show that the electron heating mode in such plasmas is sensitive to changes of the gap at a constant pressure of 3 Pa. At a gap of 1.5 cm, the dominant mode is found to be a hybrid combination of the Drift-Ambipolar (DA) and the α-mode. As the gap is increased to 2 cm and 2.5 cm, the bulk power absorption and ambipolar power absorption decreases, and the DA mode decays. When the gap reaches 3 cm, the α-mode becomes more prominent, and at a gap of 3.75 cm the α-mode is dominant. These mode transitions are caused by a change of the electronegativity and are found to affect the discharge characteristics. The presence of the DA-mode leads to significant positive electron power absorption inside the bulk region and negative power absorption within the sheaths on time average, as electrons are accelerated from the bulk towards the collapsed sheath. The heating mode transitions result in a change from negative to positive total electron power absorption within the sheaths as the gap increases. When accounting for secondary electron emission, the transition of the heating mode can occur at shorter gaps due to the enhanced plasma density and decreased electronegativity.

Numerical investigation of diamond complementary logic integrated circuits

Silicon complementary metal oxide semiconductor (CMOS) technology drives the integrated circuit industry due to its energy efficiency. The narrow bandgap of silicon has led to the development of wide bandgap semiconductor materials, such as diamond, favored in power electronics, radiofrequency and extreme environment applications. Here we have established a model of the diamond CMOS logic inverter for the first time and successfully simulated the static and dynamic characteristics. The simulated physical model and relevant model parameters are well calibrated with experimental data of diamond p-FET in the literature. The simulation results demonstrate that the all-diamond CMOS inverters possess rail-to-rail operation and excellent inversion characteristics, with the peak gain of 83 V/V, the transition region of 0.25 V, and the noise margins for low and high level of 2.44 V and 2.26 V under VDD = 5 V. Particularly, all-diamond CMOS inverters have improved performance compared to the diamond-GaN inverters, operating at 500 °C with well-preserved inversion characteristics. This thermal reliability indicates that diamond CMOS inverters can be better monolithically integrated for applications in high-temperature environments in the future.

Machine learning based feedforward voltage control for buck converters in envelope tracking applications

Tracking the voltage envelope of 5G base station power supplies poses a significant long-term challenge. To achieve fast and accurate envelope tracking, an efficient and high-frequency power electronics circuit and an excellent voltage controller are essential. This paper presents a novel machine learning (ML) based feedforward control method for precise voltage reference tracking. The method is exemplified using a standard buck converter in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM). A feedforward neural network (FNN) is trained to capture non-ideal and non-linear effects in real circuits. An automated data collection system, developed with MATLAB and Simulink, facilitates data acquisition and model training process. The trained FNN predicts the duty cycle for the buck converter to generate the targeted output voltage and output power. A simulation model is built to validate the effectiveness of the FNN controller in envelope tracking applications.

Solid State Transformer: An Overview of Application and Advantages

Abstract: Solid-state transformer (SST), Electronic power transformer or Power electronic transformer (PET) contain the transformer inside the AC-TO-AC converters or DC-TO-DC converters. SST is type of electric power converter that replaces a conventational transformer used in electric power distribution.SST carries the full power and provides the electrical isolation. This paper gives the information of the solid state transformers advantages and applications

Future visions of ai enhancing industries and navigating ethical landscapes

AI has been called a disruptive force across modern technology, cutting across healthcare, management, manufacturing, and creative industries. AI applications include diagnosis and treatment of diseases, automation and quality guarantee at production lines, optimization of network traffic in the telecommunications segment, and the enrichment of artistic creation. Recently, AI has found an increasing integration into power electronics, software engineering, and the oil and gas industry, pumping up efficiency and reducing operational costs. Looking ahead to the future, AI offers enormous potential for improvement in predictive analytics and personalized medicine in health care, the infrastructure of smart cities, and the job market. These also raise significant ethical, social, and technological concerns. Discussing bias, ensuring security, and improving data quality goes hand in hand with the responsible development of AI. Effective policy and regulatory frameworks from all levels and collaboration with international efforts are needed to unlock AI's potential and mitigate its risks, opening the path toward a positive future with AI.

Improved Model-Free Predictive Control of a Three-Phase Inverter

Model predictive control (MPC) performance depends on the accuracy of the system model. Moreover, the optimization algorithm of MPC requires numerous online computations. These inherent limitations of MPC hinder its application in power electronics systems. This paper proposes a two-part solution for these challenges for a three-phase inverter with an output LC filter. The first part of the control scheme is a linear and modified model-free approach based on the auto-regressive structure (ARX) with exogenous input. The second part is the computationally efficient optimization algorithm based on the active set method to solve the optimization problem of the MFPC. The objective of the control scheme is to regulate the output voltages of the inverter in the presence of constraints. The constraints are the maximum admissible filter current and optimal duty cycle to avoid any damage to the system. To validate the performance of the proposed control scheme, simulations and hardware-in-loop (HIL) real-time investigations have been performed, comparing the results of the proposed approach with the model-based predictive control. The results showcase the computational efficiency and effectiveness of the MFPC approach, demonstrating its potential for overcoming the limitations of traditional MPC in power electronics systems.

Optimizing Distributed Generation in DC Microgrids: A Comprehensive Study

This thorough examination offers a critical analysis of the intricate relationship between Distributed Generation (DG) and DC microgrids. It provides a thorough analysis of basic ideas, sophisticated control techniques, technological developments, and useful applications in actual situations. In the framework of a paradigm shift towards decentralized energy solutions, this study investigates the efficacy of Direct Current (DC) microgrids in integrating and optimizing diverse distributed generation sources. The study conducts a critical analysis of the challenges and possibilities related to various distributed generation technologies and renewable energy systems. For scientists, engineers, and policymakers engaged in the challenging task of incorporating dispersed energy into current systems, it offers crucial perspectives. This review is an important tool that advances our knowledge of distributed generation in DC microgrids. It contributes significantly to the development of discussions on resilient and sustainable energy solutions. In addition to discussing the challenges associated with DG integration, this study highlights real-world examples that highlight the adaptability and efficiency of DC microgrid designs. Because it includes a thorough examination of power electronics, energy storage, and advanced control systems, this study is an invaluable resource for stakeholders hoping to take advantage of DC microgrids. Through the integration of analytical analysis and pragmatic application, this review provides insightful analysis and field assistance. The entire study contributes significantly to the advancement of distributed generation (DG) integration, which is necessary to establish a sustainable and resilient energy environment. It offers the fundamental knowledge required to accomplish successful integration. This review paper offers an in-depth analysis of DG integration in DC microgrids. This review is to provide a comprehensive overview of the dynamic landscape where distributed energy generation and DC microgrids interact, starting with the foundational ideas and moving on to a close examination of the difficulties, innovations in technology, and useful applications.

High quality heavy Sn doping β‑Ga2O3 film with high mobility grown by time division transport Metal Organic Chemical Vapor Deposition

High-quality heavily Sn doped homoepitaxial β-Ga2O3 films with high mobility were deposited on (100) Ga2O3 substrates using long-distance time division transport method by Metal Organic Chemical Vapor Deposition. The structure, composition, Raman, and electrical properties of the films with different Sn source flow rates were investigated in detail. The room temperature carrier mobility of 139.89 cm2/(V·s) is attained at a RT donor concentration of 2.78×1019 cm-3, with a peak mobility of 444.9 cm2/(V·s) at 114 K. This RT mobility is currently the highest at the same doping concentration level. Furthermore, combined with the analysis of the first-principles calculation results, it is revealed that time dependent transport technology is beneficial to modulating the substitution mode of Sn replacing GaII more often. The conclusions of this study are significant to broaden the potential application of ultrawide bandgap gallium oxide in high-power microwave and power electronics devices.

An enhanced 13‐level triple voltage gain switched capacitor inverter with lower power electronics devices

AbstractIn this study, a 13‐level switched‐capacitor inverter with triple voltage gain is proposed. The proposed structure generates 13‐level output voltage using only one DC source, eleven switches, and three capacitors. The capacitors have the capability of self‐balancing without the use of additional circuits or complex control methods. Additionally, the inrush current of the capacitors has been reduced using a soft charging method. The proposed structure has been compared with different 13‐level structures presented in recent studies in terms of various parameters such as the number of semiconductor devices, the number of DC sources, voltage gain, Maximum Blocking Voltage (MBV), and Total standing Voltage (TSV). Another advantage of the proposed structure is the non‐use of any diode and its cost‐effectiveness. In addition, the power losses of the proposed structure have been evaluated, and its efficiency has been calculated for various output powers. Finally, the performance of the proposed structure has been verified through simulation and laboratory implementation under both stable and various dynamic conditions.