Energy Transformation System Research Articles

Analysis of the Impact of Hybrid Power System on Teachers' Psychology and Teaching Environment under Smart Energy Transformation and Energy System Planning

For this paper we study the structure and operational characteristics of plug-in hybrid Vs, Using the life-cycle evaluation method, The analysis model of energy consumption and environmental impact of plug-in hybrid electric vehicle fuel cycle suitable for China's national conditions is established, With the unit mileage of the plug-in hybrid car as the functional unit, Using the whole vehicle NEDC test cycle and combined with the relevant literature, Fuel consumption and environmental emission factors for this functional unit, The fuel cycle energy consumption, conventional gas emissions and greenhouse gas emissions are obtained, Evaluate the effect of power structure change on the above indexes, And compared the plug-in hybrid vehicles with conventional gasoline vehicles and compressed natural gas vehicles. As follows: compared with the current technical level of gasoline cars, under the background of road traffic, plug-in hybrid car fuel consumption is reduced by 40.7% less than gasoline cars, VOC, NOx, SO2 and greenhouse gas emissions than traditional gasoline vehicles reduced by 31.5%, 15.2%, 66.7% and 55.8%, this to alleviate increasingly severe urban air pollution is of great significance. Plug-in hybrid vehicles offer advantages over traditional gasoline cars in terms of energy consumption and emissions, both at the vehicle level and throughout the fuel cycle. Energy consumption is 56.3% lower, including a 56.4% reduction in crude oil usage, reducing oil dependency and promoting energy security. Environmentally, plug-in hybrids emit significantly less than gasoline cars, with VOC, NOx, SO2, PM10, and CO emissions reduced by up to 56%. Greenhouse gas emissions, including N2O, CH4, and CO2, are also lower. Additionally, emissions tend to be concentrated upstream, facilitating centralized pollution control.

Harmonic Resonance Mechanisms and Influencing Factors of Distributed Energy Grid-Connected Systems

With the rapid development of global energy transformation and new power system, ensuring the stability of distributed energy grid connections is the key to maintaining the reliable operation of the whole power system. This paper constructs detailed impedance models of grid-following (GFL) and grid-forming (GFM) inverters using a harmonic linearization method and thoroughly investigates the mechanisms of resonance when inverters are connected to the grid, as well as the impact of model parameters on the stability of the grid system. This paper also briefly analyzes the scenario where distributed energy and electric vehicles are integrated into the grid simultaneously, demonstrating that grid system stability can be ensured in complex grid situations through reasonable parameter design. Lastly, the accuracy of the proposed impedance models and analysis is verified through MATLAB/Simulink simulations.

EMHD micropolar fluid flowing through a micro‐structural slipped surface with heat source/sink and chemical reaction

AbstractThe electromagnetohydrodynamic (EMHD) has a vital role due to its importance in aerospace and plasma physics, including energy transformation systems in which interaction between the liquid and magnetic field is crucial. Further, micropolar fluids with microstructural slip is used in the lubrication and liquid crystals. From this observation, the current study is conducted to express an EMHD flow of liquid on a microstructural slipped surface. The effects of a uniform heat source/sink (HS/S) with homogeneous and heterogeneous chemical reactions have been incorporated in energy and mass profiles. The governing equations are converted to ordinary differential equations using proper similarity variables. The converted equations are computed by the implementation of Runge–Kutta–Fehlberg (RKF) 4th 5th order with shooting technique. A list of the essential dimensionless constraints and graphs showing how they are affected are provided. The outcome of the problem shows that the electric parameter will improve the velocity but decline the microrotation profile. Further, both heterogeneous and homogeneous reactions have a decreasing concentration. While the heat distribution rate increases with greater magnetic and electric fields, the surface drag force decreases.

Analysis of Minimum Rotational Inertia Requirements for Power System Frequency Stability

With the advancement of energy transformation and new power systems, large-scale integration of new energy to replace synchronous generators is leading to insufficient inertia in the system, threatening stable frequency operation. Evaluating the minimum inertia requirements of power systems is beneficial for improving the integration capacity of new energy and ensuring secure and stable operation. This paper establishes a mathematical model of frequency dynamics after a fault and advances an approach to assess the minimum rotational inertia requirements. The proposed approach is tested on the modified WSCC-9 bus system to validate its efficacy.

Research on the Attack Strategy of Multifunctional Market Trading Oriented to Price

In the context of energy transformation and power market system reform, it is crucial to address the network risks associated with enhancing the integration of the “Energy–Information–Market” paradigm. This necessitates research on multi-energy market trading modes and the corresponding offensive and defensive technologies. This paper proposes a novel approach centered around a node-local Energy Hub (EH) that represents large industrial users with diverse energy demands. To facilitate multi-energy two-way trading, a price-oriented Transactive Energy (TE) market clearing strategy is developed. Building upon this transaction network framework, a data-driven attack strategy targeting the state estimator of the Transmission System Operator (TSO) is introduced and implemented in two stages, encompassing real-time topology estimation and False Data Injection attacks. By leveraging Matrix Transfer Entropy (MTE), the optimal attack target is identified to disrupt the economic stability of the system and the profit of the attacker increases significantly. The proposed attack strategy is validated through simulations conducted on a 30-node system, yielding conclusive evidence of its effectiveness while offering vital insights for system defense.

Solar district heating system in Latvia: A case study

The ever growth of urban population has caused the increase of energy demand. This situation challenges the global public to find a way to produce energy in a secure, environmentally friendly, flexible, renewable and sustainable energy transformation system. One of the most promising technologies that can over-come most of the challenges is the district energy network. This paper focuses on best practice project in Latvia – fully renewable district heating system assisted by solar collector system with thermal storage tank and woodchip boilers. The article demonstrates solar impact to district heating system (DHS) in the framework of the current situation of DHS in Latvia by creating simulation in TRNSYS and validation with real system operation data. Real operational data show that the heat produced by solar collector system with thermal energy storage (TES) per year will cover up to 20% (10933,2 MWh) of the heating demand in under local climate conditions. The TRNSYS simulations concluded that the contribution of this type of solar system integrated into the DHS could be increased up to 50%, if the difference between consumption and heat produced by solar collectors were to be increased during the summer months, this could be achieved, for example, by increasing the solar collector field area.

On the role of energy infrastructure in the energy transition. Case study of an energy independent and CO2 neutral energy system for Switzerland

The transition towards renewable energy is leading to an important strain on the energy grids. The question of designing and deploying renewable energy technologies in symbiosis with existing grids and infrastructure is arising. While current energy system models mainly focus on the energy transformation system or only investigate the effect on one energy vector grid, we present a methodology to characterize different energy vector grids and storage, integrated into the multi-energy and multi-sector modeling framework EnergyScope. The characterization of energy grids is achieved through a traditional energy technology and grid modeling approach, integrating economic and technical parameters. The methodology has been applied to the case study of a country with a high existing transmission infrastructure density, e.g., Switzerland, switching from a fossil fuel-based system to a high share of renewable energy deployment. The results show that the economic optimum with high shares of renewable energy requires the electric distribution grid reinforcement with 2.439 GW (+61%) Low Voltage (LV) and 4.626 GW (+82%) Medium Voltage (MV), with no reinforcement required at transmission level [High Voltage (HV) and Extra High Voltage (EHV)]. The reinforcement is due to high shares of LV-Photovoltaic (PV) (15.4 GW) and MV-wind (20 GW) deployment. Without reinforcement, additional biomass is required for methane production, which is stored in 4.8–5.95 TWh methane storage tanks to compensate for seasonal intermittency using the existing gas infrastructure. In contrast, hydro storage capacity is used at a maximum of 8.9 TWh. Furthermore, the choice of less efficient technologies to avoid reinforcement results in a 8.5%–9.3% cost penalty compared to the cost of the reinforced system. This study considers a geographically averaged and aggregated model, assuming all production and consumption are made in one single spot, not considering the role of future decentralization of the energy system, leading to a possible overestimation of grid reinforcement needs.

Standalone nickel layered double hydroxide and nickel oxide electrodes as effective anodes in alkaline direct methanol fuel cell

Direct methanol fuel cell is an emerging energy transformation system with the prospect of substituting secondary batteries soon due to their exciting features. One of the most limitations is the weak catalytic activity of the expensive nonprecious Pt-based catalysts at the fuel cell's anode. In this work, a standalone Nickel layered double hydroxide of hierarchical nanosheet structure was effectively synthesized on the nickel foam's surface through facile hydrothermal treatment that subsequently converted into NiO without destroying the structure by heat treatment at 500 °C. The synthesized standalone electrodes demonstrated a significant activity for methanol oxidation with an onset potential of 0.35 V in KOH (1 M), which is attributed to the Ni(OH)2 (Ni+2)/(Ni+3) NiOOH active site. The electrodes effectively discharged current at 0.5 V for more than 1 h with no performance degradation compared to the bare nickel foam. The better activity of the synthesized electrodes was attributed to the nanosheet structure layer's better charge and mass transfers, as confirmed by the morphological images (SEM images) and the electrochemical characteristics (electrochemical impedance spectroscopy, chronoamperometry, and cyclic voltammetry).

Mitochondrial Neurodegeneration: Lessons from Drosophila melanogaster Models.

The fruit fly-i.e., Drosophila melanogaster-has proven to be a very useful model for the understanding of basic physiological processes, such as development or ageing. The availability of straightforward genetic tools that can be used to produce engineered individuals makes this model extremely interesting for the understanding of the mechanisms underlying genetic diseases in physiological models. Mitochondrial diseases are a group of yet-incurable genetic disorders characterized by the malfunction of the oxidative phosphorylation system (OXPHOS), which is the highly conserved energy transformation system present in mitochondria. The generation of D. melanogaster models of mitochondrial disease started relatively recently but has already provided relevant information about the molecular mechanisms and pathological consequences of mitochondrial dysfunction. Here, we provide an overview of such models and highlight the relevance of D. melanogaster as a model to study mitochondrial disorders.

Recent innovations in the technology and applications of low-dimensional CuO nanostructures for sensing, energy and catalysis.

Low-dimensional copper oxide nanostructures are very promising building blocks for various functional materials targeting high-demanded applications, including energy harvesting and transformation systems, sensing and catalysis. Featuring a very high surface-to-volume ratio and high chemical reactivity, these materials have attracted wide interest from researchers. Currently, extensive research on the fabrication and applications of copper oxide nanostructures ensures the fast progression of this technology. In this article we briefly outline some of the most recent, mostly within the past two years, innovations in well-established fabrication technologies, including oxygen plasma-based methods, self-assembly and electric-field assisted growth, electrospinning and thermal oxidation approaches. Recent progress in several key types of leading-edge applications of CuO nanostructures, mostly for energy, sensing and catalysis, is also reviewed. Besides, we briefly outline and stress novel insights into the effect of various process parameters on the growth of low-dimensional copper oxide nanostructures, such as the heating rate, oxygen flow, and roughness of the substrates. These insights play a key role in establishing links between the structure, properties and performance of the nanomaterials, as well as finding the cost-and-benefit balance for techniques that are capable of fabricating low-dimensional CuO with the desired properties and facilitating their integration into more intricate material architectures and devices without the loss of original properties and function.

Modeling and thermoeconomic analysis of a 60 MW combined heat and power cycle via feedwater heating compared to a solar power tower

Considering the critical role of electricity in the industrial and economic infrastructures and the large investments in this sector, it is necessary to correctly utilize and maintain this great industry. Further, due to the increasing prices of energy, environmental damages, and the limitation of non-renewable energy sources, it is increasingly important to maximize the performance of energy production and transformation systems. This study aims to model and analyze the economic exergy of the 60 MW heat and power generation power plant in the Esfahan steel company, as the installation has never been modeled or optimized. After 50 years of operation, the results of modeling the steam power plant and exergoeconomic analysis can lead to optimal operating conditions and be of benefit to the stakeholders. The findings indicate that the condenser, or rather cooling tower is where the maximum loss of energy occurs, whereas the boiler has the most exergy loss while the turbine ranks next in exergy loss. Increasing the load ratio increases the cycle efficiency, whereas maximum efficiency and the least heat rate occur at full load. However, increased load also increases energy/exergy loss. Increasing the temperature of the feedwater plus decreasing the condenser pressure can reduce energy/exergy loss.

Study of the Efficiency of Microcantilevers: Cases of Electrothermal and Electromagnetic Actuation

In following paper we propose method of energetic description for active microcantilevers. Microelectromechanical devices (MEMS), to which the microcantilevers belong, are becoming part of energy generation and transformation systems. Therefore efficiency of said devices becomes significant parameter. In our approach we described the method to estimate the efficiency based on the measured parameters of a cantilever and it’s effective movement under actuation. We have conducted measurements an calculations for series of cantilevers actuated electrothermally and electromagnetically. Acquired results are in line with predicted properties of examined MEMS’. Method is suited for description of microcantilevers, assessment of utility and comparison in case of common application. [2022-0043]

Energetic Competencies in Electronic Engineering Education: A Sustainable Social Commitment

Abstract: In this article, we present electronic engineering as a discipline called to propose solutions to achieve energy sustainability. This field of knowledge has been supported to accelerate energy consumption with technological contributions to al low the comfort s of the modern world. Consequently, electronics has influenced advances such as transport systems, innovations in means of communication, automation of production, domotics, and all direct impacts in the economic, political, and educational sectors. In the same way, it is then possible for electronic technology to promote development both in generating energy resources in a sustainable way and by reducing micro and macro consumption. Up to now, engineering education has promoted scientific and technological training to provide solutions that address the different needs of society, including alternative energy transformation systems. However, it has not been concerned with including in each lesson an awareness of energy efficiency and developing solutions based on sustainable use of energy. Up to now, engineering education has promoted scientific and technologicaltraining to provide solutions that address the different needs of society, including alternative energy transformation systems. Nevertheless, it has not been concerned with including in each lesson an awareness of energy efficiency and developing solutions based on sustainable use of energy. As a resource of help, we propose in this work the inclusion of "energy competences" in each topic and learning space from an Electronic Engineering program. The work presented shows that it is possible to include energy competences in electronic engineering curricula as a part of an educational sustainable social commitment. Keywords: Learning spaces, sustainability, energy, engineering education, energy competencies, syllabus.

Electromagnetic transient characteristics and overvoltage suppression strategy of renewable energy-oriented power system connected by gas-insulated transmission lines

New energy systems, such as wind power and photovoltaic and distributed power supply, in the power generation and grid-connected transmission system basically will use stronger insulation design, higher operational safety, and smaller footprint GIL equipment, while the new energy transmission system of the smart grid development trend requires accompanying the electronic transformer equipment to promote a large area. However, the current GIL equipment used in new energy transmission systems has caused great electromagnetic interference to the electronic equipment due to the compact layout of the equipment and the transient signals generated by normal operation, which has seriously restricted the development of smart grids and became a major obstacle to the grid connection of new energy systems. In order to study the characteristics and developmental law of transient electromagnetic interference signal of GIL equipment in new energy transmission and transformation system, this study proposes a dynamic arc model based on an optimized arc extinguishing criterion, verifies the correctness of the improved dynamic arc model through theoretical analysis, simulates calculation combined with the test measurement data, and compares and analyzes the simulation results with test measurement data to study the transient electromagnetic interference source signal during arc burning duration. The simulation results and test data are compared and analyzed to study the pulse steepness, size of the wave head, and overall waveform development law of the transient electromagnetic interference source signal during the arc burning process. It is concluded that the dynamic arc model based on the optimized arc extinguishing criterion can be better used to study the transient electromagnetic interference signal in the GIL equipment. Meanwhile, the transient electromagnetic interference signal has the characteristics of large amplitude and high frequency, the maximum overvoltage can reach 1.9 p.u., the UHF can reach 30 MHz, and the wave head rise time is about 12 ns. This study provides theoretical support for subsequent research on suppressing transient electromagnetic interference source signals, improving the anti-electromagnetic interference performance of electronic devices, and is dedicated to solving the obstruction problem in the process of grid connection of new energy transmission and substation systems.

Study of Electrical Output in Photogalvanic Cell for Solar Energy Conversion and Storage: Lauryl Glucoside-Tartrazine-D-Fructose System

Objective: The present study is focusing on the role of surfactant in photogalvanic cells and how photons from sunlight can be used as a driving force for energy solar energy conversion and storage. Methods: An H shaped cell was designed for study of electrical output in solar transformations. Electrical circuit was proposed by using of dye, reductant, surfactant, NaOH, double distilled water (DDW), multi-meter, calomel electrode, 250 k roistered, saturated calomel electrode, platinum electrode, carbon pot, resistance key, digital pH meter, microammeter, and 200 W tungsten bulb. A detailed reaction mechanism for the proposed photogalvanic cell (PG Cell) for generating photocurrent and photocurrent has been studied. PG Cells were studied for the solar energy transformation system. Findings: PG Cells were studied by using different parameters via photocurrent, photopotential, conversion efficiency, fill factor and cell performance. The above values are as follows: 388.0 □A, 1141.0 mV, 0.7995%, 0.5389 and 129.0 minutes. Electrical output of the cell has also been observed for tartrazine, D-Fructose and lauryl glucoside systems. Potential at power point, Potential at open circuit, power point of cell (pp) and current at short circuit were also studied. The obtained values are as follows: 1133 mV, 1523 mV, 435.321 and 544mA. Novelty: The photogalvanic is an emerging field of research for conversion and storage of solar energy. This study employs lauryl glucoside-tartrazine-D-fructose system for better electrical output which is also an eco-friendly natural dye system. The observed results are better in cell performance (t1=2) and reduction in cost (INR 9531.38 / USD 125) of the photogalvanic cell for its commercial viability. Keywords: Photogalvanic cells; solar energy conversion; storage; lauryl glucoside; tartrazine

Covalent organic frameworks for applications in lithium batteries

AbstractWith the stone energy increasingly dried up and the environment polluted severely, developing renewable clean energy is already in extreme urgency. Exploiting new energy storage and transformation systems has progressively become the focal point in the energy research field. Covalent organic frameworks (COFs) have attracted extensive attention as a new kind of crosslinked polymers owing to the high crystallinity, excellent porosity, and favorable stability. The last decade has witnessed the great progress in crystalline COFs for the application in various arenas. The tailor‐made functional skeleton together with well‐defined periodical alignment has endowed COFs with enormous potential in lithium batteries. In this review, we initially illustrated the design principle of COFs for the application in lithium batteries. Furthermore, we made a comprehensive summary of the fast‐developing COFs field in terms of lithium batteries, including lithium ion and lithium sulfur batteries. Finally, we discussed the remaining challenges and perspectives in this area and also proposed several possible future directions of development for lithium batteries. It is expected that this short review would contribute to the development of COFs materials in energy‐related applications.

Facile construction of a novel binder-free graphene/polyimide foam-based Au electrode for H2O2 electroreduction

Fuel cells have described their potential applications for novel-generation energy storage/conversion devices. Herein, an original 3D Au/reduced graphene oxide(RGO)@Polyimide(PI) foam (denoted as 3D ARP) electrode was constructed via a facile reduced graphene oxide and metal Au simultaneous in situ reduction and self-assembling process on the PI foam. The PI foam support material, modified with RGO nanosheets and well-dispersed Au nanoparticles, exhibits distinctive structural, ensuring a significant promotion towards hydrogen peroxide (H2O2) electroreduction under acid conditions. Such an open 3D hierarchical structures may provide a number of exposed catalytic activity sites and generate interconnected channels between solid and liquid interface for highly efficient mass transport. The electroactivity of 3D ARP electrode was systemically investigated by linear sweep voltammetry (LSV), cyclic voltammetry (CV) and chronoamperometry (CA) measurements. Results indicate that the as-developed electrode presented an impressive electrocatalytic behavior. As expected, the 3D ARP electrode displayed an optimized reduction current density in acid media (880 mA cm−2 at - 0.2 V). What's more, the obtained 3D ARP electrode still represented robust stability, a small apparent activation energy value (11.442 kJ mol−1), good reproducibility and repeatability (840 mA cm−2 after 1000 cycles with a 0.0053% current density decay per cycle at - 0.2 V). Such an original catalytic electrode might be an alternative for novel energy transformation systems.

Design and performance evaluation of solid oxide-based fuel cell stack for electric vehicle system with modified marine predator optimized fuzzy controller

The Fuel Cell (FC) included electric vehicle is a fast-growing research area in the current automotive industry. Also, the fuel cell offers many features when associated with the other non-conventional energy transformation systems. The FC is one of the renewable sources which is providing efficient solutions in the excess power demand areas and it is the most important upcoming continuous energy supply system. In this work, a Solid Oxide (SO) fuel composite has been considered for transferring one form of the chemical energy to another form of electrical energy. The SO fuel stacks are having plenty of advantages due to their solid materials and high working temperature which are expressed as less electrolyte loss Maintenance, and no need for electrolyte portions. The major disadvantages of SO fuel cells are electrolyte materials maintenance and nonlinear power supply characteristics curves. These drawbacks are optimized by employing the Modified Marine Predator (MMP) concept. The MMP methodology controls the fuzzy system size with a few sensing devices. The reduced number of sensing devices based Fuzzy Maximum Power Point Tracking (FMPPT) technique is utilized for obtaining the maximum output power of SO fuel cell. The merits of the proposed MMP controller are optimum design cost, smooth performance, more flexibility, and is high efficiency.

Ce-Substituted Spinel CuCo2O4 Quantum Dots with High Oxygen Vacancies and Greatly Improved Electrocatalytic Activity for Oxygen Evolution Reaction.

Exploring effective electrocatalysts for oxygen evolution reaction (OER) is a crucial requirement of many energy storage and transformation systems, involving fuel cells, water electrolysis, and metal-air batteries. Transition-metal oxides (TMOs) have attracted much attention to OER catalysts because of their earth abundance, tunable electronic properties, and so forth. Defect engineering is a general and the most important strategy to tune the electronic structure and control size, and thus improve their intrinsic activities. Herein, OER performance on spinel CuCo2O4 was greatly enhanced through cation substitution and size reduction. Ce-substituted spinel CuCeδCo2-δOx (δ = 0.45, 0.5 and 0.55) nanoparticles in the quantum dot scale (2-8 nm) were synthesized using a simple and facile phase-transfer coprecipitation strategy. The as-prepared samples were highly dispersed and have displayed a low overpotential of 294 mV at 10 mA·cm-2 and a Tafel slope of 57.5 mV·dec-1, which outperform commercial RuO2 and the most high-performance analogous catalysts reported. The experimental and calculated results all confirm that Ce substitution with an appropriate content can produce rich oxygen vacancies, tune intermediate absorption, consequently lower the energy barrier of the determining step, and greatly enhance the OER activity of the catalysts. This work not only provides advanced OER catalysts but also opens a general avenue to understand the structure-activity relationship of pristine TMO catalysts deeply in the quantum dot scale and the rational design of more efficient OER catalysts.

Design and Implementation of the Isolated Bidirectional DC-DC Converter

With the development of intelligent distribution networks and the increasing demand for new energy access, the isolated bidirectional dc-dc converter has become a key link in modern energy transformation systems. In order to realize the functions of electrical transformation and electrical isolation of dc voltage, this paper proposes a structure of isolated bidirectional dc-dc converter, and analyzes it in detail. The proposed isolated bidirectional dc-dc converter can not only realize voltage transformation, but also have voltage regulation and fault isolation functions. Finally, based on the MATLAB/Simulink simulation platform, the proposed isolated bidirectional dc-dc converter topology is built and verified by simulation. The structure of isolated bidirectional dc-dc converter not only has the functions of voltage transformation and electrical isolation, but also has fault isolation, power flow control and other functions.