bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental study of coupled solar and air source heat pump heating system
Authors: Li Xu Lin , Wang Xing , Wang Yun Long 
Published: May 2023

Abstract
To increase the heating stability and system energy efficiency as well as to offer technical assistance for promoting and deploying multi-energy coupled heating technology in village and township buildings, a solar-air source coupled heating system is suggested and developed. The experiment was conducted on a multi-energy coupled heating system for a village and town office building in Hun nan New Area, Shenyang City, over a period of 15 days, with an average daily solar radiation intensity of 558.62 w/m2-h and an average outdoor temperature ranging from -18.3 °C to -2.7 °C. The trial findings demonstrated that all indoor temperatures could exceed 18 °C while the system was in use, and the average value of the system’s overall energy efficiency was 2.45.
Development and Application of Laser Cleaner for Disconnecting Switch Rust
Authors: Zhang Jing , Zhang Xu , Zhang Min , Zhang Haoyu , Zhu Shengrong 
Published: May 2023

Abstract
The timely and regularly clean for long-time use disconnecting switches are important for prolonging their lifetime. Laser cleaning for metal rust has the advantage of zero pollution. Fast speed and parameters can be adjusted to various sites. This paper introduces the development of laser cleaner for rust on disconnecting switches. Comparing results under different parameters in labs and sites, this paper concludes that when the laser power is 20W and the scanning speed is 2500mm/s, the device has a better cleaning effect.
Research on Distributed Photovoltaic Grid-connected Mode Based on PSASP
Authors: Wang Wenlong , Cai Nan , Song Baiyue , Guan Wanlin , Xu Mingyu , Liu Yanlong , You Chao , Ma Jiancheng 
Published: May 2023

Abstract
With the continuous implementation of the carbon peak and carbon neutrality, a large number of distributed solar power stations have been integrated into the grid, which has caused a strong impact on the safe and stable operation of the traditional power system. Based on this, the grid-connected mode of distributed solar power stations is studied, and three types of grid connection are proposed. Mode A is merged into the 66 kV bus side of the 220 kV substation through the 66 kV dedicated line; Mode B is merged into the 66 kV bus side of the 66 kV substation through the 66 kV dedicated line; Mode C is T-connected to the 66 kV transmission line through 66 kV dedicated line. By using a power system analysis software package (PSASP), we can build a model of a certain regional power grid and study the effects of the above three grid-connected modes on system voltage stability, short-circuit current, and network loss. The study shows that the three modes are all feasible. Mode A has the smallest change in voltage quality and short-circuit current of the grid-connected substation and has the smallest network loss of the three modes.
Photovoltaic Power Generation Based on Three-port DC-DC Step-down Circuit
Authors: Wang Lulu , Xu Handan , Li Wenjing , Song Mingxin 
Published: May 2023

Abstract
In this paper, the photovoltaic cell is combined with the analog battery pack and the load through a three-port DC-DC Buck circuit, which gives power to the analog battery pack and load. From the perspective of simulation, the photovoltaic cell is lowered to reach respective specific values through the two Buck circuits at the output end of it and to give power to the load and the simulated battery pack. The influence of Pulse Width Modulation (PWM) duty ratio output on voltage and the influence of PWM frequency on load voltage and current limiting resistance of the power supply system is studied from the angle of power conversion. The results show that when the PWM duty ratio is changed, the actual output voltage does not reach the theoretical value, and is somewhat less than the theoretical value. When the frequency is less than 100 KHz and the inductance value is less than or equal to 100 uH, under the same other conditions, the load voltage decreases first and then increases with the increase of frequency. The larger the inductance value is, the faster the voltage drops, and the smaller the inductance value is, the faster the voltage increases. When the inductance reaches 250 uH, the inductance value continues to increase, which has little influence on the load voltage, and the load voltage generated by different inductance values only has a small error. If the output frequency of PMW is too high or too low, the output voltage will be reduced. The maximum voltage value is between 90 and 100 KHz. When the current limiting resistance is 18.5 Ω, it is close to and does not exceed the maximum charging voltage of the analog battery string.
Analysis of Laser Cleaning and Rust Removal Technology for Substation Isolator Switches
Authors: Zhang Haoyu , Zhang Jing , Zhang Xu , Zhu Shengrong , Zhang Min 
Published: May 2023

Abstract
After running for a long time, isolator switches are prone to be covered with dirt and corrosion. Switch cleaning is necessary for good operation and safety. Laser cleaning technology for rust removal is emerging in recent years. This paper introduces the technical principles of laser cleaning for rust removal in detail, designs a specific process scheme and takes a steel plate sample cleaning and rust removal as a case. The application effect of laser cleaning and rust removal technology is tested and shows that the technology analyzed in this paper can play a great cleaning effect without damaging the equipment base.
Assessment method of large-scale distributed power consumption capacity for rural grids
Authors: Li Chao , Lu Tianguang , Han Xueshan 
Published: May 2023

Abstract
As the scale of photovoltaic (PV) access continues to expand, both transmission and distribution grids are experiencing systemic consumption problems, with rural distribution grids being particularly prominent. An accurate assessment of distributed power consumption capacity is crucial to the improvement of distributed power consumption capacity. Firstly, taking into account the uncertainty of the output of the distributed power supply and comprehensive consideration of power quality, reliability of the electricity supply and operational influences, A comprehensive index evaluation system has been established to assess the ability of distributed power sources to consume; secondly, hierarchical analysis and improved gray correlation analysis are used to assign weights to the indexes; finally, a Monte Carlo model is used to identify the consumption capacity of rural power grids. This method can provide a comprehensive and accurate assessment of the consumption capacity of large-scale distributed power sources in new rural power grids, and also provide data support for solving the problem of new energy consumption in power grids.
Study on the Operation Scheme of Distribution Network Considering Voltage Stability and High Permeability Photovoltaic Access
Authors: Dong Anqi , Gao Hui , Li Huailiang 
Published: May 2023

Abstract
With the introduction of high-density distributed photovoltaic (DPV) into the distribution network, the reasonable evaluation of the voltage stability during the operation of the distribution network has become a research hotspot. In this paper, firstly, the influence of distributed photovoltaic on the voltage after it is connected to the distribution network is analyzed. Then, by building the hybrid simulation platform of MATLAB and Opendss, the change of the operation state of the typical distribution network when it is connected to the photovoltaic energy of different permeability and different capacity is analyzed. Two key nodes affecting the photovoltaic access capacity are introduced. The accuracy of the theoretical analysis was verified by the time series simulation analysis, and the general rule of the high-capacity photovoltaic access scheme was obtained based on the simulation results.
Virtual Oscillator Control for inverters based on reduced-order Andronov-Hopf oscillator
Authors: Guo Xiaolong , Kang Pengpeng , Yang Guixing , Song Pengfei , Shi Yafan 
Published: May 2023

Abstract
This paper proposes a virtual oscillator control method by reducing the order of the amplitude term of the Andronov-Hopf dynamic process. The proposed oscillator retains its steady-state droop characteristic and power dispatchability in grid-connected mode, but with less nonlinearity. At the same time, based on the steady-state performance criterion of the inverter, the detailed parameter selection principle of the proposed controller is given, and its dispatchability is verified by simulation. Finally, we compared the proposed controller with the full-order virtual oscillation controller. The results show that the proposed controller has a stronger load capacity.
A full-automatic test system for the intelligent substation based on GOOSE/SV signal simulation
Authors: Chen Yongxin , Li Hengxuan , Yang Gang , Xiao Yeqing , Wu Hao , Shi Yichuan , Chen Chongxiang 
Published: May 2023

Abstract
With the wide application of one-key sequence control in intelligent substations, the testing of one-key sequential control and error prevention logic has become an important work before production. Due to the limitation of testing methods, most of the tests are conducted during on-site commissioning, which has a large workload, lower efficiency, and a high probability of missed testing. Therefore, this paper proposes a full-automatic test system for the intelligent substation based on GOOSE/SV signal simulation. It can automatically verify the error prevention logic and the one-key sequence control of the monitoring system through the combination of GOOSE/SV signals at different statuses, which provides technical support for the site to improve efficiency and safety.
Research on refined prediction of coastal wind power based on dynamic downscale and deep learning prediction
Authors: Zhang Yi , Zhang Feng , Qiu Yutao , Yao Xudong , Liu Ang , Mo Jianguo , Xie Xiahui 
Published: May 2023

Abstract
With the expansion of the installed capacity of offshore wind power, its impact on the safe operation of the power grid is increasingly obvious, and improving the prediction accuracy of offshore wind power power has become a key problem to be solved in the industry. The improvement of prediction accuracy, on the one hand, can facilitate the operation control of power grid, on the other hand, can also significantly improve the economic benefits of wind power plants. Based on power downscaling and deep learning methods, this paper carries out localized short-term and ultra-short-term power prediction modeling and optimization technologies for coastal offshore wind power. Comprehensive statistical prediction method, artificial intelligence prediction method, multi-model integration method and other combined prediction model, multi-source fusion information, to realize the refined prediction of Zhejiang offshore wind power, and improve the overall prediction accuracy. The research method is generally applicable and can guide the output prediction of the same type of offshore wind power.
Study on the start-up control strategy of DFIG wind farm via MMC-HVDC grid connection
Authors: Wang Qian , Wu Shouyuan , Song Yu 
Published: May 2023

Abstract
The flexible DC transmission technology proposed in recent years has significant technical advantages over other transmission methods for long-distance grid-connected transmission of large-capacity wind farms. However, as the scale of wind farms continues to expand, new problems have emerged, mainly in the form of start-up control as the basis for the reliable grid-connected operation of wind turbines. In this paper, a start-up control strategy for DFIG wind farms connected to the grid via MMC-HVDC is proposed for DFIG wind farms via flexible DC outgoing transmission scenarios, mainly including MMC-HVDC controlled rectifier start-up control and single DFIG start-up control. Finally, the correctness and feasibility of the proposed control strategy are verified by simulation.
Study on the aerodynamic performance of inlet pipe different bending radius of ram air system
Authors: Liu Xiaohong , Xia Fuming 
Published: May 2023

Abstract
In this paper, the bending radius deviation of the intake duct is studied. The computational fluid dynamics (CFD) method is used to evaluate the performance of the inlet by the coupling calculation of the internal and external flow of aircraft. Firstly, the CFD method is used to calculate the theoretical numerical model. The results show that when the pipeline flow is constant and the pipeline R/D decreases, such as from 1.84 to 1.3, the total pressure recovery decreases, especially when the pipeline R/D is less than 1.5, the total pressure recovery decreases rapidly. At the same time, the drag force of the pipeline does not change much, and the flow field of the inlet pipeline is analyzed to analyze the internal reasons for the total pressure recovery and flow rate change with R/D, which has important guiding significance for the application of batch production in future.
Temperature Field and Thermal Stress Analysis of Rocket Engine Composite Structure Nozzles
Authors: Liu Yunpeng , Feng Feng , Shen Xiaodong , Chen Chao 
Published: May 2023

Abstract
As one of the core components of the rocket engine, the working conditions of the nozzle are very bad. Ensuring the nozzle works normally is an important prerequisite for the normal operation of the rocket engine. To ensure the safety of the solid rocket motor nozzle in use, the temperature distribution and thermal stress of the nozzle must be preliminarily analyzed. Therefore, the three-dimensional model of an L-shaped nozzle is established. The temperature field and stress field of the structure is numerically simulated by FLUENT and Static Structural. The influence of gas temperature and material thermal conductivity on temperature distribution and thermal stress of solid structures are analyzed. The results show that the throat has the highest temperature and maximum thermal stress. When the gas temperature is 2600K, the maximum temperature of the throat is 1400K, and the thermal stress is 158MPa. When the thermal conductivity of the insulation layer is 2.8 W/(m·K), the thermal stress on the throat is 170 MPa. The conclusion can provide an important reference for the thermal protection design of the nozzle.
Research on the influence of pilot workload on local route path planning of helicopters in low-altitude penetration
Authors: Li Shen , Li Pan 
Published: May 2023

Abstract
Targeting the problem of high pilot workload caused by trajectory planning of low altitude penetration, this paper proposed a trajectory planning method considering the pilot workload. Firstly, by decomposing the three-dimensional trajectory into horizontal and vertical directions, the trajectory tree method based on the dynamic programming technique is used for horizontal trajectory planning, and the comprehensive slope-curvature limitation method is used for altitude trajectory planning. Then, a method was proposed to quantify the control inputs and pilot workload based on trajectory tracking simulation. The pilot workload cost, together with flight altitude cost and route length cost, was added to the local planning of a reference trajectory. To solve the problem of dimension explosion in trajectory tree search, a segmented optimal route tree algorithm is proposed. Finally, the simulation results show that the proposed method can effectively consider the pilot workload in trajectory planning, which is helpful to improve the flight ability of the planning trajectory and reduce the pilot workload at the same time.
High-fidelity Modelling Approach for Investigating the Tightening Torque Effect in Thread Connection
Authors: Zhang Hui , Yu Fei , Wang Houbin 
Published: May 2023

Abstract
Accurate replication of the torque-tightening effect is important when simulating the mechanical behavior of composite joints using the finite element (FE) approach. In this study, a parametric mesh construction strategy was developed to automatically build a high-fidelity 3D FE model with lift angle to simulate bolt thread interactions. An experimental approach was proposed to calibrate the FE model. The relation between tightening torque and the axial force was studied by the FE method, experiment, and engineering algorithm. Results showed that traditional empirical formula overestimate the clamping force. By using the proposed model to calculate the axial force of the bolt, the accuracy of the axial force can be significantly improved when analyzing the composite bolted joints. Finally, parametric simulations were performed to investigate the influence of coefficients of friction at thread interfaces and the nut/washer interfaces. The pre-tightening force was significantly influenced by the frictional coefficients at these interfaces. Results indicated that increasing the coefficient of friction (CoF) at the nut/washer interface from 0.1 to 0.2 can lead up to 28% reduction in the clamping force, while this increase was 23% for the threads interfaces.
Feasibility of autonomous orbit keeping with optimal fuel consumption using drag-free CubeSat
Authors: Liu Rui , Wei Donghua , Liu Yingying , Liu Yiheng 
Published: May 2023

Abstract
In this paper, the composition of the drag-free CubeSat platform was introduced first. Then the control strategy of drag-free CubeSat orbit keeping was proposed. Finally, the simulation with the control scheme of the Homan transfer orbit was compared. By comparing and analyzing the fuel consumption of the drag-free track and Homan transfer track, it is demonstrated that the continuous drag compensation of the drag-free control scheme can significantly reduce the consumption of thruster mass, and the drag-free technology has good advantages in track stability.
Key Failure Mode Identification Method of LED System Based on Fuzzy TOPSIS
Authors: Zhang Bing , Hao Zhaojun , Wang Lifang , Li Lexiao 
Published: May 2023

Abstract
The premise of the system reliability analysis is to effectively discern the patterns of product failures at all levels. To deal with the problem that the diversity of failure modes of complex products represented by LED systems cannot be analyzed comprehensively, in this paper, a key failure mode identification method based on Fuzzy TOPSIS is proposed. First, the construction method of the failure relevance tree is given to support the comprehensive identification of potential failure modes. Then, the decision rule of node failure weight is mined by the rough set method, the systematic evaluation of the node failure weight is realized with the TOPSIS method, and the key failure modes are identified. Finally, a case validation of the proposed method in this paper is performed.
Effectiveness Evaluation of Medium-sized Carrier Rockets Based on ADC Method
Authors: Wang Jianjun , Xu Zhensen , Zhou Tao , Zhang Jun , Wu Xiangqing 
Published: May 2023

Abstract
Using scientific evaluation methods to evaluate the mission effectiveness and cost-efficiency of rockets is one of the important topics in the development of rocket models. Aiming at the problem that the effectiveness evaluation of carrier rockets cannot be quantitatively analyzed, this paper takes the medium-sized carrier rockets, covering both new and old generation ones in service, as the object of establishing a simplified inherent capability index system. The ADC method is utilized to quantitatively evaluate the availabilities, dependabilities, and capabilities of various types of rockets and calculates the corresponding effectiveness and cost efficiencies when performing launch missions in LEO, GTO, and SSO orbits. The results show that Model II has excellent mission effectiveness, which is particularly suitable for medium and high orbit missions; the cost-efficiency of Model III is as good as that of the former, and it can complete many tasks; but Model I is outdated.
Pseudo-Theory-Based Optimization Design Method for Lunar Gravity-Assisted Human Earth-Mars Transfer Trajectory
Authors: Yuan Yiting , Zhao Zichen , Dong Yue 
Published: May 2023

Abstract
The lunar gravity assist (LGA) is recognized as one of the potential ways to reduce the energy demand of human Mars exploration. Nevertheless, it indeed increases the difficulty of designing the exploration trajectory due to its inevitable considerations of a more complex gravitational environment and additional flying stages. Focusing on this issue, an efficient pre-design method is proposed on the basis of the pseudo-state theory. By embedding the pseudo-sweep back step into the dynamical propagation, the accuracy of two-body trajectories can be recovered to a high level, which brings significant convenience of initially designing high-precision trajectory, rapidly searching the departure window, and fast evaluating the LGA effect. A large amount of simulation results show that the application of the pseudo theory could enhance at least 88% trajectory accuracy, increase the 60% success rate, and decrease 5% the necessary cost when optimizing the Earth-Mars transfer trajectory, with comparisons to the two-body trajectory.
Simulation and analysis of drag for inflatable aerodynamic decelerator
Authors: Yun Chenghu , Liu Danghui 
Published: May 2023

Abstract
Inflatable aerodynamic decelerator, as a novel deceleration and recovery technology, has received attention due to its lightweight and freedom from the launch vehicle fairing size constraints for the space mission. Aimed at the aerodynamic characteristics of the inflatable aerodynamic decelerator, this work studied the effect of the cone angle on its drag and discussed the drag varied with the angle of attack under the different cone angles. The simulation showed that the drag was affected by the cone angle and increased locally with the angle of attack. Furthermore, the larger cone angle was beneficial to the stability of the flow field on its leeward in the case of a high Mach number. The math model of drag with the Mach number and the angle of attack was obtained by fitting the data, which provided favorable support for the prospective discussion of the flight dynamics characteristics.
Technical analysis on airworthiness compliance of lighting components for civil aircraft emergency evacuation slides
Authors: Song Hongyuan , Li Feng , Tang Xiaoliang 
Published: May 2023

Abstract
The emergency landing safety of emergency evacuation slides can be improved greatly by using lighting components, especially in dark environments. To design a required lighting system, two problems need to be solved, which are also the focus of this paper. Firstly, what airworthiness compliance work should be planned and how to do it. Secondly, how to design to meet the airworthiness requirements should be considered. A complete and effective airworthiness compliance method was proposed by analyzing various performance characteristics such as self-opening function, lighting duration, illuminance, and installation environment. Airworthiness requirements are decomposed into design features, and the design requirements of lighting components are put forward. This study can provide verification methods and design ideas for the lighting components of civil aircraft emergency evacuation slides.