bluuebunny/crossref_metadata_2025_split huggingface dataset:
Start-up and Transient Support Control of AC-DC Hybrid Distribution Networks with Distributed PV Access
Authors: Li Ke , Lin Yuqing , Li Guoliang , Wang Long 
Published: July 2024

Abstract
For AC-DC hybrid distribution networks, a large number of interconnecting converters connected to DC micro-sources and DC distribution networks in the distribution network provide a powerful aid for restoring power supply to the loads in the lost area after an accident by using the local power supply of the system, and at the same time, the power synchronisation control strategy provides a friendly power supply mode for the power supply of the interconnecting converters to the passive network. This paper analyses the start-up control of AC-DC hybrid distribution networks with distributed photovoltaic (PV) access under the scenario of interconnecting converter multi-machine co-operation in transferring power to a load area without a superordinate power supply; and puts forward a power synchronous control of interconnecting converter multi-machine co-operation to suppress power-frequency oscillation under faults of a distribution network without a superordinate power supply.
Power System Planning Based on Cost Correction with High-Penetration of Renewable Energy
Authors: Su Rong , Jiang Ying , Wang Leqi 
Published: July 2024

Abstract
The growing prevalence of renewable energy has led to a greater impact on power grid planning due to the inherent indeterminacy and variability in renewable energy output. The establishment of a power grid planning system that can effectively accommodate large-scale renewable energy generation holds significant practical importance. Given the vast magnitude of optimization decision-making, the number of scenes and time granularity in the planning model are limited, and its cost data cannot reflect the impact of considering renewable energy with high penetration, resulting in inaccurate planning scheme. Then some conditions after operation simulation may exceed the planning expectation or cost a lot. Based on the problems, this paper proposes a planning-oriented cost model parameter feedback correction method based on the planning scheme simulation data. The planning scheme is simulated to get simulation data, which is subsequently used to compute more precise setup parameters. According to these parameters, a more accurate planning scheme is obtained. Finally, combined with an example, the simulation results of the conventional power grid planning model and the planning model with cost correction are compared, and the rationality and effectiveness of the proposed method are verified.
Research on lightning strike location by OPGW optical sensing based on extreme sliding window and wavelet
Authors: Yang Jie , Gao Xiang , Hou Jun , Chen Xianda , Shao Shuai 
Published: July 2024

Abstract
Lightning strikes usually affect the safe use and normal operation of the power grid. It is crucial to accurately identify and position the lightning strikes. The lightning current on OPGW near the lightning strike point and the modulated lightning intensity signal waveform were simulated. The polarization state signal of Faraday optical fiber will mutate when it is struck by lightning. The extreme value unit sliding window energy method was used to extract the initial time window of the signal after a lightning strike, and the three alternative windows with the maximum energy were determined. Then the maximum wavelet coefficient is determined to be the first wave time point of the struck signal. Simulation analysis and engineering field application show that the optical polarization signal characteristic of OPGW can be used to accurately locate the lightning strike point, which can meet the needs of practical engineering applications of power systems.
Two-layer Optimization-Based Capacity Allocation Method of Integrated Energy Systems
Authors: Xue Yuantian , Wang Yudie , Yan Gaoshan , Zhang Hongtian , Wei Chun 
Published: July 2024

Abstract
In this paper, the coupling relationship between energy sources is used to carry out analysis and establish the capacity allocation and optimization model of the integrated energy system. Then a two-layer optimization algorithm is used to establish a linear programming model, which is simulated and analyzed according to the data of a certain region, and solved by CPLEX. The simulation results show that the multi-energy complementary has a good economy and can improve the cleanliness compared with the traditional energy system, which well proves the effectiveness of the proposed capacity optimization model and operation strategy of the integrated energy system.
Ambient Signals based Load Modeling with Two Three-phase Induction Motors
Authors: Han Shenghua , Zhang Xinran , Huang Wanjun , Ling Zihan , Ling Xiaobo , Ye Zheng 
Published: July 2024

Abstract
The traditional electric power system simulation and calculation are based on the simple load model including one motor and one static load. On the one hand, the power system load is getting more and more complex. On the other hand, it’s proved that two kinds of three-phase induction motors will show a little difference. As a result, in this paper, a new model load with two three-phase induction motors is proposed. Besides, the dynamic of the power system load is taken into account. The torque of those two three-phase motors will show different characteristics, that one is constant and the other is variable. Formerly, the dynamic of the load is regarded as the result of an induction motor. However, the single-phase motor and electronic load both lead to the complexity of the load. To get a more accurate calculation, we need a more proper load model. One of the ways to improve the load model is to pay more attention to the ingredients ignored. The single-phase motor and power electronic load make a great difference. Besides, it’s proved that the composited load model with two three-phase motors will be better in the calculation.
Passive Radiative Cooling Materials and Their Applications
Authors: Jia Rongrong , Gao Baohai , He Mingjian , Ren Yatao , Qi Hong 
Published: July 2024

Abstract
Passive radiative cooling naturally lowers the temperature of a cooler by reflecting sunlight and emitting heat into the frigid expanse of universe. While certain natural and synthetic substances may exhibit distinct radiative properties, their radiative efficiency remains minimal. As a result of the notable advancements in micro-nano technology, scientists have created several novel substances that exhibit minimal absorption within the intense solar spectrum (0.3-2.5 μm) but possess elevated emissivity in alternative wavelengths, ideally falling in the atmospheric window spectrum (8-13 μm). The basics of radiative cooling mechanisms are presented in this review, along with an overview of the progress made in radiative materials and their various applications. In upcoming times, this technology of passive radiative cooling, which consumes no energy and produces no greenhouse gases, will become a prominent approach for cooling purposes.
State-of-Charge Estimation of Reconfigurable Supercapacitor
Authors: Li Boyu , Ma Yueyue , Zhu Ren , Li Heng 
Published: July 2024

Abstract
A large body of research has been done on state-of-charge (SOC) estimate of supercapacitors in the literature; most of the works have been on SOC estimation of individual supercapacitor units. Nonetheless, supercapacitors are usually linked to balancing circuits in real-world applications in order to remove inter-cell imbalances. The cells’ system dynamics shift to a new mode when the balancing circuit is turned on, making the SOC calculation techniques that are currently in use inappropriate. Our proposal in this research is a Kalman filtering-based reconfigurable supercapacitor balancing system SOC estimate method. By fusing a reconfigurable balancing circuit with the equivalent circuit model of supercapacitors, we create a linear switching systems model. The switching system’s discrete-time form is shown, and its observability is examined. With filter gains dynamically modified according to the system mode, a switching Kalman filter is intended to estimate the SOC of the switched system. The accuracy of SOC estimation is greatly improved by the suggested method when supercapacitors are in the balancing mode, as confirmed by the simulation results.
Energy Management Considering both Efficiency Optimization and Lifetime Balance of Multi-stack FCS
Authors: Lv Xin , Shen Jiabin , Guo Xiaoyu , Li Ce , Zhou Honglei , Dong Zhen 
Published: July 2024

Abstract
With the increase of energy transformation and environmental protection awarenesses, fuel cells, as a clean and efficient energy conversion technology, have been widely adopted in transportation and stationary power supply applications. A single fuel cell has a limited power capability. On the other hand, the multiple fuel cells are combined into a multi-stack fuel cell system (MFCS), which provides a high power output and modular design. However, the energy management of such multi-stack systems faces challenges such as uneven power distribution, inconsistent stack life, and low overall efficiency. Current multi-stack fuel cell control systems often optimize single objectives, either efficiency or lifetime balance produce the optimized energy management strategy. This may not suffice for the overall system benefit. For example, if only efficiency is optimized by energy management, the failure to consider lifetime balance may result in uneven life degradation for each fuel cell, and vice versa. To address the above issues, this paper proposes an energy management strategy for multi-stack fuel cell systems that considers dual objectives, which can simultaneously ensure the optimal co-optimization of the output efficiency and stack life for each stack, thereby improving the overall operating efficiency and lifetime of the system. The effectiveness and practicality of the proposed energy management control strategy were verified on a 60kW dual-stack PEMFC fixed power generation system developed by SeeEx.
Analysis of Resonance Mechanism of AC Submarine Cable Delivery System for Offshore Wind Power
Authors: Tian Shuxin , Zhou Yu , Liu Lujie , Zhang Yanjiu , Zhao Haoxing 
Published: July 2024

Abstract
Several resonant overvoltage accidents caused by machine-grid interaction in offshore wind power generation systems have led to significant economic losses over the years. To solve this problem, based on the equivalent distributed parameter circuit model of AC submarine cable delivery system, a method combining impedance simulation-time domain simulation and spectrum analysis is proposed to reveal the mechanism of resonant overvoltage and its influencing factors. First of all, considering the phase locked loop (PLL) model and the cable distribution parameter model, an impedance model of AC submarine cable delivery system for offshore wind power is established, which takes into account the dynamic characteristics of PLL and current loop, and provides a model basis for the theoretical analysis. Then, equations for current and frequency at the point of common coupling (PCC) are derived to analyze the mechanism of resonant overvoltage generation and the influence of submarine cable length and power grid strength on resonance. Finally, PSCAD is used to verify the resonance mechanism of AC submarine cable delivery system and its influencing factors.
Analysis of DC Bias in Magnetic Controlled Shunt Reactor and Its Influence on Interturn Protection
Authors: Guo Xiao , Xing Wu , Wang Zhe , Zhu Yucong 
Published: July 2024

Abstract
Magnetic controlled shunt reactor is widely used in new energy transmission, and its special operation characteristics provide dynamic reactive power compensation for the power system, while the reactive power capacity can be continuously adjusted, solving the problem that conventional fixed reactance cannot be applied to reactive power demand fluctuations. This paper briefly introduces the structure and working principle of a magnetic controlled shunt reactor, analyzes the relationship between core magnetic saturation and control current in a magnetic controlled reactor under different DC bias conditions, and the reliability of interturn protection under different working conditions is studied and a feasible scheme is proposed, provides a certain reference for the design and operation and maintenance of magnetic controlled shunt reactor.
Research and Application of New Anti-Condensation System of High-Voltage Switchgear
Authors: Wang Jiayi , Kou Jianqiang , Xia Yankun , Zhou Dianbo , You Mingfu 
Published: July 2024

Abstract
The drastic fluctuations in temperature and humidity in the switchgear environment can lead to condensation, posing the threat to the safe and dependable operation of power equipment. In response to the limitations of current anti-condensation measures, a new anti-condensation system for high-voltage switchgear is proposed. Firstly, this research provides an overview of the cause of condensation and the present situation of relevant prevention technologies. Secondly, a new anti-condensation system for high-voltage switchgear is presented. Drawing upon existing anti-condensation technology, this system effectively addresses prevalent issues such as high air humidity and facile condensation in high-voltage switchgear. Electric field simulation calculations, conducted using COMSOL simulation software, demonstrate that the system does not compromise the normal operation of the switchgear. Finally, practical applications show that the robust operational stability of the system. It consistently achieves precise heat dissipation and dehumidification in high-voltage switchgear, which has high application value.
Passive Equilibrium Circuit for Lithium-Ion Battery State of Charge Balance
Authors: Xie Peng , Chen Rongxing , Xu Wenqiang , Guo Zhiyang 
Published: July 2024

Abstract
Lithium-ion batteries serve as pivotal energy storage solutions in electric vehicles and portable electronics. Precise State of Charge (SOC) estimation is crucial for optimizing battery performance and ensuring longevity. This paper introduces an innovative approach utilizing passive equilibrium circuits for enhanced SOC estimation. The passive balancing circuits actively equalize voltage levels among individual battery cells during both charging and discharging, thereby improving SOC estimation accuracy. The proposed method is implemented and simulated using Matlab Simulink, demonstrating superior performance compared to traditional methods. Simulation results reveal the effectiveness of the passive equilibrium circuit in diverse operating conditions, offering a promising solution for accurate SOC estimation. This research contributes to the advancement of battery management systems, with potential applications in renewable energy storage.
Experimental study on the influence of different sampling methods on the stress-strain and strength characteristics of weathered and water rich sandstone
Authors: Yang Chaoshuai , Lei Shengyou , Yue Xijun , Zou Chong 
Published: July 2024

Abstract
In order to explore the physical and mechanical properties of layered weathered sandstone in a water rich environment, the authors obtained layered sandstone from the tunnel excavation section. Firstly, the physical properties and chemical composition were tested, and then uniaxial tests were conducted on sandstone, in which the loading direction was divided into perpendicular to the specimen bedding, parallel to the specimen bedding, and at a 45 ° angle to the specimen bedding. The uniaxial test results show that the stress-strain curve of sandstone is strain softening type. The uniaxial compressive strength of sandstone is between 2.18 MPa and 28.123 MPa, the residual strength is between 0.122 MPa and 24.284 MPa, the elastic modulus is between 5.843 MPa and 49.45 MPa, the Poisson’s ratio is between 0.303 and 0.484, and the softening coefficient of rock is between 0.15 and 0.20. The uniaxial compressive strength of sandstone samples subjected to blasting disturbance is 38% of that without blasting disturbance, and the elastic modulus is 30% of that without blasting disturbance. The axial and radial strains of sandstone samples significantly increased after blasting disturbance. Blasting significantly reduces the uniaxial compressive strength and elastic modulus of the sample. The uniaxial strength of sandstone decreases exponentially with increasing water content.
Preparation and application of waste cigarette butts-derived mulch film with excellent mechanical properties and optical transparency
Authors: Liu Xianjie , Huang Sijun , Li Genrong , Zhang Qiuquan , Zhang Haitao , Yang Youyu , He Fengjie , Sun Donghong , Ma Zhipan , Huang Jufen 
Published: July 2024

Abstract
The small waste cigarette butts every year worldwide added up is a significant threat to the environment. The main component of cigarette butts is cellulose acetate, which is an excellent film-forming material. Here, a one-step phase transition method was employed to successfully convert waste cigarette butts into a transparent film. This film (160×18×0.5 mm) derived from waste cigarette butts (CB) has high mechanical strength (fracture stress 23.5 MPa, Young’s modulus 13.1 MPa), good thermal stability, and excellent optical transmittance (91.8%), and low haze (40.3%). Its properties rival those of traditional low-density polyethylene (PE) film. Meanwhile, the CB film displayed fascinating bending-ability and folding resistance. The cigarette butt-derived film with low cost and excellent properties exhibits a promising application as agricultural mulch and provides recycle solution for waste cigarette butts.
The research of vibration localization under strong disturbances using modal analysis methods
Authors: Huang Chunwen , Ji Gang 
Published: July 2024

Abstract
Vibration localization is a typical feature of aperiodic structures. This work investigates the vibration localization of framed cylindrical shells with a high disturbance degree. First, the spring oscillator system is considered an example to reveal the general law governing how high disturbance degree influences the vibration transmission in a structure. Then the strong localization coefficient is calculated using the modal analysis method. Finally, the conclusions of the one-dimensional systems are applied to the two-dimensional structures based on the passband approximation equivalent method to derive the strong localization coefficient of the aperiodic ring-ribbed cylindrical shell. This study realizes quantitative calculation of the vibration localization coefficient under high disturbance degree. The results of this work provide theoretical support for reducing the vibration transmission performance of a structure by increasing the degree of disturbance.
A Current-Mode bandgap reference with robust start-up behaviour
Authors: Chen Bingjie , Liu Xue , Wang Xin’an 
Published: July 2024

Abstract
Bandgap reference with robust start-up behavior has an important role in analog circuits. In this paper, conventional current-mode bandgap reference (CMBGR) structures are investigated, along with the problem of conventional structures having multiple operating points during start-up. A CMBGR structure that can eliminate all the operating points by a simple start-up circuit is proposed. The CMBGR proposed in this paper utilizes the 180 nm technology and achieves a nominal temperature coefficient of 16.05 ppm/°C. The circuit consumes a current of 6 μA and occupies an effective area of 0.046 mm2.
Optimum frequency tracking of the ultrasonic motor based on a three-level constant voltage drive
Authors: Cai Kangwei , Fu Ping 
Published: July 2024

Abstract
Ultrasonic motors are widely used in aerospace, smart cameras, and other applications. For ultrasonic motors to have the highest operating efficiency, the operating frequency of the motor needs to be adjusted in real time so that the motor’s operating frequency tracks the optimum frequency. Since the current research is limited to the optimum frequency tracking under constant velocity, the three-level drive parameters need to be adjusted to stabilize the velocity, which lacks precision and does not consider the frequency tracking under variable velocity. This paper explores an optimum frequency tracking scheme for ultrasonic motors under the three-level constant voltage input drive and proposes a variable step-size optimum frequency tracking scheme. The experimental results show that the optimum frequency of ultrasonic motors in variable velocity motion exists, and the proposed tracking scheme with three-level drive parameters can effectively improve the efficiency of the motor and significantly broaden the application scenario of the optimum frequency of ultrasonic motors.
Analysis of gap distance of ultra high voltage AC transmission lines in areas with altitude above 2000m
Authors: Su Yu , Ma Xiaoxu , Zhou Songsong , Liu Delong , Jiang Ling , Xie Shijun 
Published: July 2024

Abstract
Research on long-wave front discharge characteristics of lines and long gaps of substation equipment in high-altitude areas needs to be conducted in a systematic manner immediately in order to guarantee the safety and economy of high-altitude UHV lines with respect to external insulation. However, at present, the gap discharge test of transmission lines is mainly carried out in areas below 2000m above sea level. The actual test is challenging to conduct in the high altitude region, and the test data is incomplete. To further confirm the validity of extrapolation of existing altitude test data to high altitude areas, this paper conducts theoretical analysis based on the real test data under standard meteorological conditions provided by GB/T 24842 standard. The altitude correction methods in IEC 60071-2: 2018 and IEC 60060-1: 2010, the m-coefficient method and g-parameter method, are used to correct the lightning impulse, power frequency, and standard switching impulse of AC transmission line gaps. The discharge voltage in areas below 5000m above 2000m is obtained, and several significant discharge characteristic parameters are obtained. Based on the 50% discharge voltage requirements of various voltage types of 1000kV transmission lines, combined with the discharge voltage curves at multiple altitudes, the minimum air gap distance of transmission lines at the altitude of 2000m-5000m is obtained. The comparative analysis of the correction results of the two methods provides a way of thinking for the next step to carry out the true test of UHV AC transmission line gap discharge in higher elevation regions.
Microgrid energy management strategy based on LSTM-DDQN
Authors: Xin Peiqi , Wang Hongtao , Wang Haobo , Xu Changmeng 
Published: July 2024

Abstract
This paper introduces a novel algorithm, LSTM-DDQN, designed to address the stochastic economic dispatch problem in microgrids. The inherent variability and randomness of photovoltaic (PV) energy pose challenges for accurate output prediction. Traditional approaches, including physical and statistical methods, often fall short in terms of accuracy. For microgrids with a high proportion of PV generation, we propose a new algorithm that combines Long Short-Term Memory (LSTM) neural networks with the Double Deep Q-Network (DDQN) algorithm. The algorithm leverages the LSTM model to capture the uncertainty of the learning environment and optimizes the Q-value iteration rules in the DDQN algorithm, thereby enhancing the training speed of the neural network. Experimental results demonstrate the algorithm’s remarkable dispatch capabilities in managing the interplay between PV generation, battery capacity, and overall load demand. This algorithm provides robust support for the stable operation of microgrids.