bluuebunny/crossref_metadata_2025_split huggingface dataset:
Model-based improvement of a trans-critical CO2 refrigeration plant
Authors: Fatigati Fabio , Battista Davide Di , Carapellucci Roberto , Cipollone Roberto 
Published: December 2024

Abstract
Refrigeration sector including heat pumps, cryogenics and air conditioning is responsible for a share close 10% of the global greenhouse gas emissions. Therefore, a huge effort of the scientific and industrial community is needed on the development of technologies allowing to reduce the environmental impact of this sector. The use of CO2 as working fluid has great interest in food chain conservation and participates to the problem of the impact produced by the traditional synthetic fluids, recently oriented also to hydrocarbons. Main problem of plants using CO2 as working fluid is the low COP, which reduces even more in moderate or hot climate regions in which low temperature thermal energy is more required. To assess the benefits introduced by plant optimization and innovative technologies, many advanced thermodynamic models are developed in the last years. Anyway, few software platforms are developed for the comprehensive analysis of plant behaviour. To fill this gap, this paper presents the results of a theoretical and experimental research done on an industrial trans-critical CO2 refrigeration plant. The aim was to set up energy saving solutions finalized to mitigate the intrinsic low COP values. A detailed physically consistent model of the unit has been developed following an integrated zero and mono-dimensional thermo-fluid-dynamic approach. The propagative, capacitive, and inertial properties of the components have been considered, so going beyond of the theoretical approaches that are typical in the sector. A wide experimental characterization of the unit has been done with the aim to validate the model and to use it as tool to predict the effect on the COP of the operating variables. The reduction of the compressor absorption and the potentiality of the energy recovery from energy usually wasted have been analysed.
Solar-Powered Refrigeration for Sustainable Refrigerated Transport
Authors: Petruzziello Fabio , Cilenti Claudio , Grilletto Arcangelo , Maiorino Angelo , Aprea Ciro 
Published: December 2024

Abstract
Solar-powered refrigeration systems offer a feasible and promising solution for enhancing the sustainability of refrigerated transportation. This paper provides a comprehensive overview of the design and construction of a solar-powered refrigeration unit tailored for a refrigerated van, featuring photovoltaic (PV) panels mounted on the rooftop of the refrigerated box. The key components and operational mechanisms of the unit are also highlighted.
The study reports on five preliminary experimental tests conducted to validate the feasibility and efficacy of a transport refrigeration unit (TRU) powered by solar energy. These tests demonstrate the impact of the PV solar system on the energy balance of the refrigerated unit under various environmental and operational conditions. The results indicate that the photovoltaic system enables autonomous operation of the refrigeration unit for 2.5 hours at a set point of -18°C (suitable for frozen products) and over 5 hours at +4°C (suitable for fresh products), assuming afternoon deliveries starting at 14:00 with climatic conditions typical of June and July in Fisciano, Salerno, Italy. These findings support the feasibility of sustainable regional and inter-regional transportation. The study also evaluates the effect of different starting times, revealing an increase in the duration of autonomous operation by up to 35% for transportation at 0°C when the start time is shifted from 14:00 to 11:00.
Furthermore, the research assesses emission savings, identifying reductions between 4.1 and 4.4 kgCO2,e per delivery at set point temperatures of -18 °C and +4 °C, respectively. This range is even wider when considering earlier starting time (up to 5.4 kgCO2,e per delivery in the tests performed). This underscores the significant potential of solar-powered solutions in advancing the decarbonization of the cold chain.
This research aims to inform policymakers and technology developers about the potential of deploying solar-based solutions in the refrigerated transport sector.
Energy flexibility potential associated with thermal uses in prototypes of Italian single-family buildings.
Authors: Zangheri Paolo , Previtali Nicholas , Franchini Giuseppe 
Published: December 2024

Abstract
The transition towards renewable distributed generation and the electrification of consumption will increasingly enhance energy flexibility strategies aimed at promoting self-consumption, energy sharing, and optimizing grid operation. Residential thermal loads can also contribute to these objectives, and this study aims to provide new insights in this regard. The study, based on dynamic load simulation, extends to three types of building-system setups (existing, renovated, and nearly zero-energy) in three climatic contexts (Milan, Rome, and Palermo). Characterization of the flexibility potential associated with building thermal inertia is based on appropriate indicators (Flexibility Index and Peak Load Reduction Factor) comparing consumption profiles associated with two types of internal temperature setpoint control: standard and flexible. The latter is modelled predictively, based on a penalty curve and predicted climatic conditions. Two penalty datasets are considered to represent the perspectives of the energy distributor (DSO) and the operator of a Renewable Energy Community (CER) with photovoltaic installations. The results show how the technological characteristics of building structures can influence the building’s flexibility potential. The greatest benefits are observed during the heating phase and in renovated buildings, which manage to ensure good load shifting capability and significant peak load reduction (up to 60-80%). It is interesting to note that in more efficient buildings, a large portion of flexibility potential can be achieved through energy efficiency solutions, even without flexible control.
Enhancing the prediction of electric load demand: a comparative analysis of ARIMA and ANN models for the case of a small touristic island
Authors: Galli Claudio , Superchi Francesco , Bianchini Alessandro 
Published: December 2024

Abstract
Accurate prediction of energy demand is necessary for efficient power system operation, particularly in energy systems with high renewable sources integration. This study compares different methods for predicting load demand using statistical regression. In particular, the goal is to provide insights on the differences between simpler AutoRegressive Integrated Moving Average (ARIMA) and more complex Artificial Neural Network (ANN) models. The algorithms are used to predict electric load demand in Tilos, a small Greek island with strong seasonal trends due to summer tourism. The case study is significant as Tilos’ outdated electrical grid must adapt to an increasing share of renewable energy sources, making load forecasting increasingly important. The algorithms were developed in Python using open-source tools (such as StatsModels and TensorFlow). Hyperparameters’ tuning, crucial for enhancing forecasting effectiveness, was performed using stochastic optimization with Differential Evolution to minimize RMSE. The optimal normalized RMSE was reported as 9.72% for ANN and 9.54% for ARIMA, showing the effectiveness of both methods, with a slight edge for the statistical model. This work provides critical information regarding load prediction methodologies, highlighting practical guidance for energy managers, policymakers, and researchers in power system planning and operation.
Estimating the solar potential of the rooftops of the city of Genova through the 3D modelling of the built environment and anisotropic tiled sky analysis
Authors: Memme Samuele , Lepore Davide , Priarone Antonella , Fossa Marco 
Published: December 2024

Abstract
In the present paper, the problem of the determination of yearly insolation and photovoltaic (PV) producibility of a series of selected suburbs located in the city of Genova (region Liguria), Italy is tackled through the GIS based construction of the 3-dimensional built environment and proper modelling of hourly solar energy availability. The input data include local climate conditions, as inferred from local hourly insolation data as 12-year averages of global and diffuse irradiance data from PV-GIS-SARAH platform. The built environment is described in terms of raster files having resolution 0.5m able to provide the 3D coordinates of building volumes, infrastructures and terrain surfaces, as kindly provided by the city of Genova municipality. The solar yield analysis is carried out by building a cumulative 3D tiled sky starting from TMY (typical metereological year) of the present location, taking into account the hourly distribution of beam and diffuse solar radiation all year round. The calculations of the building surface view factors towards the sky elements is performed within the QGIS platform by using python scripts able to calculate the superposition of reflected to direct irradiance while taking into account the mutual position of roof portions and sky dome radiating tiles. The analysis is performed also considering the near and far obstacle shadings (near buildings, far mountains). Statistical processing of selected suburbs rooftop portions showed that up to 60% of building roof are exposed to an yearly insolation above 1200 kWh/m2/yr, thus potentially able to fulfil the expected demand of PV energy of the entire Liguria at the year 2030.
Energetic and exergetic analysis of an AE-T100 micro gas turbine system fuelled by partially cracked ammonia
Authors: Monacchini Chiara , Anfosso Chiara , Bellotti Daria , Magistri Loredana 
Published: December 2024

Abstract
In recent years, ammonia has gained attention as a fuel for power generation purposes, especially due to its chemical characteristics which ensure reaching the target of zero-carbon emissions. Ammonia is also a powerful hydrogen carrier, with a solid and consolidated production method based on the Haber-Bosh process. By exploiting the ease of transport of ammonia that is liquid at moderately low pressures and temperatures, it can be converted to hydrogen and nitrogen through a cracking reaction directly at the power production plant site. Moreover, to reduce greenhouse gas emissions (GHG) in the production energy sector, small-scale power generation systems are today gaining more attention. In this context, the use of partially cracked ammonia mixtures in micro gas turbine fields represents an interesting solution in the distributed generation sector. In this work, an energetic and exergetic analysis of an AE-T100 mGT fuelled by partially cracked ammonia mixtures is carried out. The analysis has been performed by varying the ammonia cracking percentage according to the maximum achievable conversion by exploiting the thermal energy contained in mGT exhaust gases. The whole system has been modeled in MATLAB/Simulink environment and it includes not only the turbine but also the ammonia conditioning system required to bring the ammonia at the condition imposed by the mGT. Moreover, a comparison with the mGT fuelled by conventional fuel is carried out both from a thermodynamic and exergetic point of view.
Experimental characterization of the acoustic response of cavity-backed perforated plates to control thermo-acoustic instabilities in gas turbines
Authors: Bourgeolet Clément , Ceglie Vito , Laera Davide , Stefanizzi Michele , Camporeale Sergio Mario 
Published: December 2024

Abstract
Prediction and control of thermoacoustic instabilities is a major challenge in the development of modern power generation gas turbines and aeroengines. Such instabilities arise from the coupling between flame dynamics and combustor acoustic modes, resulting in severe oscillations that can lead to premature aging of combustor components and structural damage. In many combustors, passive dampers are implemented to increase the acoustic energy dissipation of the system and prevent the onset of these harmful flame-acoustic interactions. In the present study, passive damping systems based on a cavity-backed perforated plate are experimentally analyzed, with a focus on studying the impact of bias flow on the reflection coefficient over a wide range of frequencies. Tests are carried out on two cavity-backed perforated plates characterized by the same porosity but a different number of holes 25 and 49, namely P25 and P49, respectively. It is observed that, for a given plate geometry, a higher bias flow leads to an increase in the plates absorption capacity over a wider range of frequency. This is more pronounced in the P
49 plate configuration. For both tested configurations, comparing the experimental results with Scarpato model proposed in the literature [1], a good match it is observed only for low values of bias flow. The model instead is not able to correctly capture the behavior of the damping systems when higher dissipation is reached.
Sensorless PMSM control system design based on XMC1302
Authors: Zhang Kohao , Zhao Xin , Lu Xuewei , Zhou Hongqiang 
Published: December 2024

Abstract
Addressing the issues of insufficient torque, low efficiency, and limited speed regulation in traditional constant frequency ratio control of Permanent Magnet Synchronous Motors (PMSM), this paper designs a PMSM control system based on the XMC1302 microcontroller. The study focuses on how to achieve smooth speed regulation from 500 rpm to 5000 rpm without position sensors. By incorporating a rotor state estimation algorithm, the motor’s performance is significantly improved across a wide speed range. This research offers crucial theoretical and practical insights for achieving efficient and stable operation of PMSM under sensorless control.
Research on the joints of second-generation high-temperature superconducting tape
Authors: Xing Mingtian , Zhi Tengfei , Wang Luoyuan 
Published: December 2024

Abstract
The second generation of high-temperature superconducting tape (REBCO) joint technology is of great significance to the development of high-temperature superconducting magnets. Tape joints are indispensable for the development of magnets, and it is of great significance to study and improve the welding technology of tape joints to reduce the resistance of the joints and the heat load generated for the operation of superconducting magnets. In this paper, a number of YBCO superconducting joints are prepared by the welding process, using two kinds of solder, under the conditions of different welding temperatures, lap lengths, and thicknesses of solder, in order to study the effects of different process parameters on the resistance of the welded joints.
Design of thermal management system for high-power liquid-cooled charging pile
Authors: Wang Junqiang , Yang Shuqiang , Liu Yike , Tang Yingguo 
Published: December 2024

Abstract
High-power ultra-fast charging causes the charging gun to rapidly heat up, posing safety hazards. Therefore, the focus of the research is on thermal management during the overcharge process. To address this, a novel thermal management control system (TMS) for high-power liquid-cooled charging piles has been designed. The liquid circulation channels connect the cables and the charging gun, with coolant flowing through the pipes. A pump delivers the coolant to the charging gun to remove heat. The TMS monitors temperature, pressure, and flow to control the oil pump and fan speeds, maintaining the perforating gun temperature within a preset range and managing the system’s heat. This TMS system enables the liquid-cooled charging cables to carry larger currents, significantly enhancing charging power.
H∞ state feedback design based on LQR robust control for inverted pendulum system
Authors: Hu Weitao , Wang Yuxuan , Pang Aiping 
Published: December 2024

Abstract
This paper proposes a robust H∞ design method for the disturbance suppression of an inverted pendulum. Based on the LQR method, the H∞ state feedback design, which has good robustness and disturbance rejection, is provided. The H∞ state feedback problem is ultimately converted into the resolution of the Riccati equation. The key to solving the Riccati equation is how to determine the weighted matrix in the H∞ controller. This paper takes the effective bandwidth of the system, the requirements of high properties at low-frequency ranges, and the coordination between variables and other aspects into consideration, which successfully solves the many parameters’ selection problem. And the physical significance is clear. The outcomes indicate that the advanced H∞ state feedback control scheme, rooted in LQR robustness, significantly enhances the system’s capability to mitigate external interference.
Study on the effect of seasonal permafrost on soil resistivity
Authors: Yue Keyu , Zheng Yu , Zhao Hongdan , Gao Guangmin 
Published: December 2024

Abstract
In order to study the effect of seasonal permafrost on soil resistivity, firstly, the resistivity influencing factors were analysed, the soil conductivity model was established, and the effects of permafrost on soil resistivity and the number of freeze-thaw cycles on soil resistivity at different depths were analysed through simulated experimental measurements. The results show that the freeze-thaw cycle will lead to soil structure damage, internal loosening, current conduction is blocked, and resistivity increases; with the rise in the number of freeze-thaw cycles, the soil is gradually solidified, the current conduction is enhanced, and the resistivity gradually decreases and tends to be stabilised; beyond the freezing depth of the soil, the resistivity tends to be stable, almost unaffected by the freeze-thaw cycle. Moreover, in a single freeze-thaw cycle, the effect of freezing on soil resistivity gradually increases as the freezing temperature decreases.
Study on the phenomenon of nonlinear variation of VeE-max during aging of multichip parallel IGBT modules
Authors: Wang Zhichao , Meng Zhaoliang , Gao Yong 
Published: December 2024

Abstract
The aging failure of bonding wires in IGBT modules is one of the causes of module failure, and it is one of the contents of the reliability research of power electronic devices and systems to investigate the damage mechanism, evolution law, and condition monitoring method of module bonding wires. In this paper, by taking the Infineon FF450R12ME4 half-bridge IGBT module as an object, we designed a double-pulse test to verify the correlation between the module junction temperature and VeE-max, used artificial picking off the bonding wires to simulate the aging of bonding wires, and analyzed the evolution law of VeE-max during the aging process. The results show that there is a good linear relationship between VeE-max and junction temperature, which can be used as a temperature-sensitive electrical parameter to predict the junction temperature. In the aging process of bonding wire, the change rule of VeE-max is different from that of traditional single-chip IGBT modules, showing a nonlinear trend. This nonlinear variation rule provides a new reference for the reliability assessment and bonding wire condition monitoring of the module.
An intelligent diagnosis method for transformer based on CSSA-MCKD
Authors: Wang Liyu , Qin Jinfei , Chen Chunyu , Zhao Dawei , Lu Yixiang 
Published: December 2024

Abstract
In transformer fault diagnosis, the difficulties of signal feature extraction under strong noise backgrounds and the low accuracy of acoustic signal diagnosis still need to be effectively addressed. For this purpose, this paper proposes a novel transformer fault diagnosis model. The model combines an improved Sparrow Search Algorithm optimized Maximum Correlation Kurtosis Deconvolution (MCKD) with a Bi-directional Long Short-Term Memory Neural Network (BiLSTM). Firstly, to address the issue of the traditional Sparrow Search Algorithm falling into local optima, this study introduces an improved cubic chaotic mapping for initializing the population, compared to the traditional uniform distribution, this method more effectively enhances the diversity of the population, thereby improving the algorithm’s global search capability and convergence speed. Secondly, considering that the decomposition performance of the MCKD method is highly dependent on the choice of its main parameters, an improved Sparrow Search Algorithm is used to optimize these parameters, thereby enhancing the accuracy and stability of the signal decomposition. Finally, to address the issue of weak signal features in strong noise environments, this study uses optimal MCKD to perform denoising and feature enhancement on the raw data, thereby eliminating redundant interference and improving the robustness and accuracy of the diagnostic network. This paper validates the effectiveness of the proposed algorithm through comparative experiments with signal simulation and measured data.
An optimal configuration scheme of virtual capacity expansion transformers considering short-term emergency load capacity
Authors: Guo Qiang , Chen Weijun , Yao Haiyan , Li Zhonghua , Zhang Xufeng , Bian Yang , Sun Qingqi 
Published: December 2024

Abstract
As critical equipment for electrical energy transmission and voltage transformation, power transformers are fundamental to the power grid’s safe, reliable, and economical operation. As urbanization accelerates, the contradiction between the lag in constructing power transformers and the urgent need for short-term capacity expansion becomes increasingly prominent. Existing capacity expansion methods present challenges such as high costs and significant space requirements. In order to solve the problem, this paper proposes an optimized configuration scheme for virtual capacity expansion transformers, which considers the short-term emergency load capacity. Firstly, an annual average cost model of a virtual capacity expansion transformer is proposed. Then, the optimal configuration scheme is established with the highest average effective utilization rate of the transformer and the lowest comprehensive economic cost index as the optimization goal. Finally, a 220/110 kV urban power grid system is simulated to prove the advantages of the proposed scheme compared with the existing scheme.
A dynamic state evaluation method for current sensors based on reference values and time series
Authors: Zhou Ke , Meng En , Mo Zhiyue , Jin Qingren , Bao Haibo 
Published: December 2024

Abstract
Due to the complex and ever-changing power environment, when designing dynamic state evaluation methods for current sensors, there is often a problem of inaccurate calculation of state evaluation values, leading to poor evaluation accuracy of the methods. A dynamic state evaluation method for current sensors based on reference values and time series is proposed. Firstly, we normalize the time series data of the current sensor, construct a covariance matrix, calculate the degree of correlation between the time series data, and construct a higher quality current sensor state dataset. Then, we select multiple indicators as state evaluation indicators and quantify them. Then, the feature vector of the evaluation indicators and the state evaluation value are calculated. Under the influence of the reference value, we set the threshold of the current sensor in different states to divide the current sensor into different states. Through the above design, the dynamic state evaluation method for current sensors is completed. The experimental results show that the designed dynamic state evaluation method for current sensors based on reference values and time series has an average coefficient of determination of 0.95 in practical applications, with high evaluation accuracy.