bluuebunny/crossref_metadata_2025_split huggingface dataset:
Realizing the load shifting potential of residential space heating - A field study on the control input for thermostatic control of indoor air temperature
Authors: Christensen Louise R. L. , Petersen Steffen 
Published: December 2023

Abstract
Economic model predictive control (MPC) of residential space heating utilizes indoor air temperature fluctuations and thermal mass for load shifting of space heating consumption and it can be used for various demand response purposes in district heating systems. A field experiment imitating the behaviour of an MPC has previously been carried out in three residential buildings in Aalborg, Denmark. Here, digital radiator thermostats were used, and it was found that the load shifting period was cut short when using the temperature measurement embedded in the thermostat as control input for the MPC. Therefore, the field study reported in this paper investigated whether using indoor air temperature sensors as control input for the thermostat improved the realisation of the load shifting. The field study took place in a single-family house in Aarhus, Denmark, and tested the load shifting potential when controlling with either the temperature sensor embedded in the thermostat or an offset between the radiator thermostat setpoint and an indoor air temperature sensor measurement. The study indicates that the use of indoor air temperature measurements as thermostat control input will provide longer periods of loading and unloading the building, thereby increasing the total load shifting potential of the heating consumption.
Assessment of thermally activated inner building components or a high temperature stone storage system to utilize surplus renewable electrical energy
Authors: Pazold M , Hanen F , Sirtl F , Radon J , Antretter F , Kersken M , Sinnesbichler H 
Published: December 2023

Abstract
In electrical grids with high renewable percentage, the production is less demand-driven, but more dependent on weather conditions. Usually there are periodical weather patterns in the winter period with substantial amounts of wind energy production. Sometimes this results in a shut-off of the wind turbines due to the inability of the grid to use the produced power (overproduction). This paper assesses two thermal storage systems to service space heating and domestic hot water that exploit the overproduction of electricity and thereby bridge periods of lower electricity production. The first system utilizes inner walls and ceilings with a thermally activated building system (TABS) to store and dissipate heat. The second system is a stand-alone high temperature stone storage system (HTSS). Models to simulate such systems within a whole building simulation framework are introduced and the verification with measured data from field measurements is presented. Both models are used to assess the systems with regard to the speed of loading and the potential to bridge time periods without additional heating in high-performance buildings. It is shown that both systems can provide heating and domestic hot water (DHW) up to 13 days without substantial additional electricity.
Impact of artificial ageing on the performance of acrylic self-adhesive tapes
Authors: Dobilaitė V , Jucienė M , Kumžienė J , Banionis K , Paukštys V , Stonkuvienė A 
Published: December 2023

Abstract
The use of sealing tapes in creating a continuous envelope to ensure the airtightness of the building is an essential factor. The study aims to investigate the performance properties of single-sided self-adhesive tapes for building applications and to obtain the changes in these properties due to the effects of environmental factors. The tapes were glued to the different substrates. Peel adhesion, tack of the tapes, and the air permeability of sealed elements were determined. The adhesive tape were aged in the laboratory using two different methods, standard (EN 12024) and a new one, during which the test samples were exposed to the cyclic impact of the temperature and humidity of multiple levels. Analysis of the results showed that the substrate has influence on the adhesive behaviour of the self-adhesive tapes. After artificial aging, in most cases, the performance properties of the tapes do not change significantly. The novel approach allowed the comparison of the influence of different aging factors on the change in the performance properties of the tape and contributed to the development of a methodology for testing the durability of sealing tapes. The effect of substrate on tape adhesion was also investigated, which is useful from both a practical and a methodological point of view.
The Behaviour of Wood Fibre Insulation Systems for Solid Wall Buildings: Lessons from a Long-term Monitoring Study
Authors: Marincioni Valentina , Altamirano-Medina Hector 
Published: December 2023

Abstract
The majority of the traditional building stock in the UK is made of solid brick walls. Internal wall insulation is one of the possible interventions to preserve the external appearance of a building while improving the energy efficiency of its walls. However, it can lead to moisture-related risks, such as excess moisture accumulation and mould growth. This paper presents an overview of the lessons learnt from the long-term monitoring of two case-study solid wall buildings, insulated with wood fibre-based systems and monitored for a year. The aim of this monitoring campaign was to provide evidence on the main moisture transfer and storage mechanisms occurring in solid walls insulated with wood fibre-based systems under actual environmental conditions. Results showed that the dynamic interaction between the insulated wall and moisture sources could be controlled by means of an appropriate specification of the insulation system, considering the influence of orientation, material properties and indoor moisture loads. It was also found that construction moisture influenced the initial conditions of the interface, but mitigation strategies can be considered to reduce mould growth risk during installation and before the drying of construction moisture.
Comparative Assessment of the Carbon Footprint of on-site and off-site Wall Element Constructions
Authors: Fufa Selamawit Mamo , Høyli Randulf , Einejord Andreas , Johnsen Oddgeir 
Published: December 2023

AbstractOff-site construction is considered as environmentally preferable to on-site due to the controlled environment for planning and production before assembly in the construction site. However, evaluating the actual environmental benefits and drawbacks from a life cycle perspective is important to avoid problem shifting. The aim of the paper is to evaluate the environmental performance of conventional on-site construction of wall elements, in comparison with off-site wall element production in a factory and assembly on the construction site. This study has been a collaboration with a Norwegian contractor using wall constructions with elements produced either on- or off-site. The contractor seeks to reduce the negative environmental consequences from building activities by establishing a local factory for off-site element production, thus motivating this study to provide environmental inputs to a decision-making process. The wall elements which either fulfil the Norwegian building code (TEK17) or passive house (PH) standard are evaluated using three scenarios: 1) on-site construction with local materials obtained from Norwegian manufacturers/suppliers, 2) off-site wall element production and wall construction in Norway, and 3) off-site wall element production in Estonia and wall construction in Norway. The GHG emissions from the scenarios are calculated using screening LCA method for life cycle stages of production (A1-A3) and construction (A4-A5). The results show that lowest GHG emissions are attributed to local Norwegian off-site TEK-wall element production, whereas the Norwegian on-site PH-wall has the highest GHG emissions. The results also highlighted the contribution to GHG emissions of specific building materials, as well as the dependency of the results on the background data and the methodological choices used in the study.
Rain resistance of windows – Lessons learned from two decades of laboratory testing
Authors: Gullbrekken Lars , Gransjøen Therese , Andenæs Erlend , Time Berit , Kvande Tore 
Published: December 2023

Abstract
Windows are important in buildings intended for human activities as they let in daylight and provide views. However, they may also be vulnerable in terms of heat loss, air leaks, rain tightness, and durability. In Nordic climates featuring severe driving rain exposure, water tightness is of outmost importance. SINTEF has for many decades been testing windows as part of the Norwegian yearly product control. Air permeability and water tightness are tested according to NS-EN 1026 and NS-EN 1027, respectively. The windows are then classified as described in NS-EN 12207 and NS-EN 12208. This paper summarises experiences from the last two decades of testing, presenting the results of 1130 tests of windows’ air permeability and rain tightness. The overall trend is that air and rain tightness performance of the windows have improved over time. Certain hinge configurations are clearly better than others, with tilt and turn windows performing the best and top hung casement windows the poorest. There is a clear trend that highly rainproof windows also exhibit lower air permeability. Multiple-window screens fail the test more often since they feature longer perimeters of opening. The contribution of weather sweep seals to the water tightness is significant as it makes an extra rain barrier to the joint between casement and frame. In general, leakage between the frames of double windows and in the joints of the frame occurs at lower air pressures than leakages between casement and frame. The lessons learned from the survey may guide future development of weatherproof windows.
An anti-offset wireless power trasfer system with constant current/constant voltage output
Authors: Liu Zheyu , Wang Siming 
Published: December 2023

Abstract
This article proposes a wireless power transfer (WPT) system based on LCC-LCC and LC-LC series hybrid compensation topology with offset resistance and constant current/voltage output performance. The system uses LCC-LCC and LC-LC networks for input and output series and adopts a four-direction decoupled magnetic coupling structure. On this basis, by designing appropriate parameters, a constant current output independent of the load was achieved, and the performance of resisting coil offsets in the four directions of x, y, xy, and -xy can be achieved. Furthermore, a T-network facilitates the mode conversion for achieving constant current/constant voltage output. Subsequently, an experimental simulation platform was built to verify the feasibility of the theory presented in this paper.
Terahertz gas sensor and its application in gas detection of power pipe gallery
Authors: Luo Guofang , Xiong Xianghong , Chen Hongtao , Li Tengfei , Chen Xi , Han Jingxin 
Published: December 2023

Abstract
During the operation of a power cable duct, the content of flammable gas is an important element in the safety of the cable duct. The accurate detection and location of gas in the pipeline corridor are important to improve the safety and stability of the power system. In view of the change of the refractive index of the gas in the power cable tube gallery, this paper presents the important application of terahertz one-dimensional photonic crystals with high-quality factors in gas sensing, change of the gas refractive index in the tube gallery simulated, and the gas refractive index change in the tube gallery can be obtained accurately by analyzing the change of transmission peak at terahertz range, the potential of terahertz sensor in gas detection in power tube gallery is verified.
Analysis and identification of transformer acoustic signal based on compressed sensing
Authors: Li Zhong , Chen Liyang , Liu Kai , Ma Xun , Wang Yong 
Published: December 2023

Abstract
The operation state of the transformer affects the operation of the whole power system. Aiming at the application of online monitoring of transformer operation, based on compressive sensing theory and wavelet packet analysis technology, a transformer acoustic fault diagnosis method based on compressive sensing is proposed. Firstly, the partial Hadamard matrix is constructed as the observation matrix to compress the acoustic signal of the transformer. The energy decomposition of the compressed signal is completed based on the wavelet packet. Finally, the feature selection is completed by considering the energy distribution characteristics using wavelet information entropy. The acoustic signal characteristics of transformer core fault simulation data are extracted by this method, and the fault diagnosis simulation is completed by using a particle swarm -SVM classifier. The results show that this method can obtain higher fault identification accuracy under the condition of a high compression ratio.
Electric vehicle charging scheduling based on improved bald eagle algorithm
Authors: Li Ran , Bai Di 
Published: December 2023

Abstract
With the continuous promotion of electric vehicles (EVs), charging fees for EVs has gradually become a hot issue. Pointing at the defects of the bald eagle algorithm, such as slow rate of convergence and poor solving accuracy, the bald eagle search algorithm based on opposition learning and Gaussian variation (GBES) is proposed. The improved bald eagle algorithm has the characteristics of fast convergence speed and strong optimization ability. The model of EV charging cost minimum scheduling is optimized by the GBES, and its effectiveness is verified by simulation experiments.
Modeling and Reliability Constraint Analysis of MMC Valve
Authors: Wang Shuaiqing , Chen Shuai , Hu Yongjie , Hu Xuebin , Hu Qiuling , Guan Gengsheng , Zhou Xiaofeng 
Published: December 2023

Abstract
The VSC-converter valve is the core equipment of the VSC-HVDC transmission system, and its reliability directly affects the availability of the VSC-HVDC system. The reliability model of the existing VSC-converter valve mainly considers the relationship between different redundancy and the reliability of the VSC-converter valve. This paper first analyzes the impact of the failure of key components of the VSC-converter valve. According to the different effects, the arm reliability model of the VSC-converter valve is established, and finally, the comprehensive reliability model of the VSC-converter valve is established. Then, based on the model of the VSC-converter valve, the reliability constraints of the VSC-converter valve that meet the engineering requirements are finally derived. An example is given to verify the correctness of the classification reliability evaluation. Finally, according to the reliability model proposed in this paper, the design recommendations for a highly reliable VSC converter valve are given.
Maximum Power Point Tracking Based on Wind Speed Prediction
Authors: Peng Meihua , Wang Zhen , Xie Zhiqing , Yang Ziheng 
Published: December 2023

Abstract
A control method for MPPT (maximum power point tracking) based on wind speed prediction is proposed to address the issue of slow attainment of optimal speed values by wind turbines in variable wind speed conditions in the wind power system. Initially, the wind speed variation value is accurately estimated using the SSA-BP neural network based on historical wind speed data. Subsequently, the MPP (maximum power point) is calculated considering the optimal blade-tip speed ratio, thereby enhancing the tracking speed of the system. Simulation results demonstrate that this method enables real-time estimation of wind speed variation, improves wind energy utilization rate, and maximizes the utilization of wind energy.
Design and Implementation of DSP-based Three-level Simplified SPWM Modulation Method
Authors: Fan Naiwei , Wang Liejun 
Published: December 2023

Abstract
The traditional three-level sinusoidal pulse width modulation (SPWM) requires two carriers to be compared with the modulating waveform to get the duty cycle, which can not be realized in a single-core DSP chip with high requirements. This paper proposes a three-level single-carrier SPWM waveform implementation method that does not increase the hardware cost. The scheme is based on the DSP28335 chip, using the DSP chip’s increment/decrement counting method, the comparison counter, and the DSP interrupts to compare the carrier waveform with the modulating waveform and get the PWM drive signals with different duty cycles. Simulation results show that compared with the traditional three-level SPWM algorithm, the proposed three-level simplified SPWM modulation not only controls the hardware cost, but also optimizes the bias of the intermediate capacitor voltage on the DC bus side, which reduces the harmonic distortion of the grid, shortens the time for the DC output voltage to reach the steady state, and verifies the effectiveness of the proposed modulation method.
Technologies Related to Intelligent Grounding Box of High-Voltage Transmission Cable
Authors: Lv Lixiang , Xu Weilun , Liu Shanshan 
Published: December 2023

Abstract
The high-voltage cable line plays an important role in the transmission of electricity in the city network. The effective grounding of the high-voltage cable is of great significance to ensure the normal operation of the cable system. There is an increasing demand for the intelligence of grounding boxes of high-voltage transmission cables. In this paper, aiming at the heating problem of the grounding box, the overall design scheme and key technology of the cable intelligent high-voltage grounding box are proposed. The intelligent high-voltage grounding box has various electrical functions of the traditional grounding box. It also has cable circulation monitoring, waterproof, fireproof, anti-theft, and alarm functions. Remote control and management of intelligent grounding boxes can be realized through GPRS.
Research and Design of Substation Positioning System Based on Ultra-wide Band
Authors: Jia Tianyu , Qiao Jiping , Guo Fengfeng 
Published: December 2023

Abstract
Aiming at the problems such as whether the safe distance between the substation operators and the live equipment is enough and the accidental loss of the working equipment, a substation personnel and materials positioning system based on UWB (ultra-wideband) is designed. Through the development of the hardware and software of the lower computer and the upper computer, the moving target is located. The experimental results show that the positioning error is less than 7.8 cm in the one-to-one ranging mode and 20.5 cm in the three-dimensional mode, which meets the high-precision positioning requirements of the operators and equipment in the substation.
Design of Carbon Dioxide Reduction Electrolysis Stacks and Trial Production of Electrolytic Cell Prototype
Authors: Zhu Shan , Ma Fengxiang , Zhao Yue , Liu Wei , Song Yumei , Zhu Shougang , Niu Xudong 
Published: December 2023

Abstract
Currently, the electrolytic conversion of carbon dioxide (CO2) is a highly regarded and dynamic research field worldwide. The investigation and application of high-efficiency catalysts and ion-exchange membranes have emerged as prominent and sought-after research directions. This paper, in particular, centers on the design, trial production, and testing of carbon dioxide reduction electrolysis stacks. To optimize the stack performance, different plate materials were evaluated for their mechanical strength and corrosion resistance, resulting in the selection of aluminum alloy and 316L stainless steel. Furthermore, the choice of ionic membrane and carbon paper was based on Faraday efficiency and stability data, leading to the selection of DuPont Nafion anionic membrane and YLS carbon paper. Through the trial production of small electrolytic cells, the overall current density, Faraday efficiency, and durability of the chosen cell assemblies were validated. Subsequently, a KW-grade electrolysis stack was successfully manufactured, tested, and fine-tuned, achieving an impressive electrocatalytic current density of approximately 200 mA/cm2 and an impressive stability of around 400 hours.
Heat dissipation design of the mine-used inverter output filtering device
Authors: Wang Yue 
Published: December 2023

Abstract
During long-distance transmission, pulse width modulation (PWM) signals are subject to voltage reflection. This results in spike voltages and high du/dt values at the motor end. Suppression is carried out by utilizing a series reactor at the output of the inverter. And the filtering parameters are optimally designed. Then, the EMF characteristics of the output reactor are analyzed and power losses are calculated. On this basis, an integrated heat dissipation scheme is proposed to design the output reactor for forced cooling. It is verified by ANSYS/Icepak simulation, which shows that the filter has good heat dissipation performance.
Modeling and Simulation Analysis of Operation Characteristics of Supplemental Fired Absorption Heat Exchanger
Authors: Lian Xueli , Zhang Chenghu , Di Yanqiang 
Published: December 2023

Abstract
Based on a general single-segment absorption heat exchange unit, a series complementary lithium bromide absorption heat exchange unit was constructed by adding a direct combustion unit, which can achieve a lower backwater temperature on the primary side, thereby increasing the heating capacity. Based on the analysis of the thermodynamic cycle and heat-transfer process, the mathematical model was built and solved using an iterative numerical method. Based on satisfying heating load, the impact of the temperature of supply water on the primary side on the operating characteristics of the unit under different load conditions was quantitatively analyzed. The result shows a negative correlation between backwater temperature on the primary side and supply water temperature on the primary side when other parameters are unchanged. If the supply water temperature on the primary side remains unchanged, the temperature of the backwater on the primary side decreases with the increase of heating load, and the ratio of heat exchange of plate heat exchange unit to total heat exchange decreases with the increase of heating load. For example, when the supply water temperature is 120°C, the proportion of water-water plate heat exchange capacity to total corresponding to 100% heat load, 90% heat load, and 75% heat load is 0.465, 0.580, and 0.772, respectively.
Interpretable Load Patterns of Building District Energy Systems using Attention-based LSTM
Authors: Yu Hanfei , Huang Shifang , Zhang Xiaosong 
Published: December 2023

Abstract
With the increasing demand for energy and focus on environmental sustainability, district energy systems (DESs) have emerged as a promising solution. To optimize DES operations and energy savings, accurate load forecasting is crucial. This study proposed an LSTM model with an attention mechanism for accurate heating load forecasting within a real DES. By introducing an attention mechanism, the heatmaps generated by weight distribution can reveal the load pattern’s periodicity and building thermal inertia. Research on single buildings and district systems has shown that load forecasting with district systems is more stable regarding forecasting accuracy and load pattern extraction capability under irregular external disturbances. The outcomes illustrate the effectiveness of the proposed framework in accurately predicting heating loads and extracting interpretable load patterns. This can assist building managers in enhancing operational strategies, resulting in energy conservation.