bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and validation of finite element models for buckling of open-hole fiber-reinforced composites at ambient and cryogenic temperatures
Authors: Daghigh Vahid , Belk Davy M , Nikbin Kamran 
Published: December 2022

Abstract
Understanding the buckling behavior of fiber-reinforced composites (FRCs) is critical for the design of composite structures. In this study, finite element (FE) models of FRC buckling behaviors were developed and validated. The validated FE models could accurately predict the numerical and experimental observations in the literature. The effect of the specimen geometric imperfections was included in the model to secure a realistic FE model; to this end, linear buckling analyses were employed before beginning the nonlinear buckling analyses. The FRCs’ mechanical properties and buckling behavior of FRCs can be temperature-dependent. Because the presence of a hole in the design of composite structures may be inevitable in a few applications, the temperature-dependent buckling responses of open-hole glass/epoxy, glass/polyester, carbon/epoxy, and carbon/polyester composites were compared with those of the plain specimens. The effects of the fiber and resin types, temperature, and the presence of holes on buckling behavior were investigated and discussed in detail. Five different temperatures, 25, 0, −50, −100, and −180 °C were considered. The cryogenic temperatures raised Young’s moduli and consequently raised the critical buckling loads. The validated models and results on the open-hole composites can be used as benchmarks in composite structure designs involving buckling behavior.
Key Parameters of Electromagnetic Compatibility of On-line Monitoring Sensor Device for Power Converter Valve
Authors: Du Fei , Chang Wenzhi , Wang Guangzhen , Yuan Shuai , Gong Yanpeng 
Published: December 2022

Abstract
Converter valve is the key equipment of power grid, the safety and reliability deeply affect the reliability of power grid. In the industry, infrared and discharge sensors have been widely used to realize on-line condition monitoring. However, devices’ failure and accuracy reduced often happen, and the complex electromagnetic environment caused by converter valve are difficult to resisted. It is necessary to study the electromagnetic interference produced by the converter valve in order to guide the electromagnetic compatibility design of the sensor or monitoring device. Based on the typical electromagnetic interference mode, the interference models of converter valve elements are established, and the calculation methods of EMC of converter valve are proposed. According to FDTD method, the electric field distributions under the operation and impulse voltage are calculated, based on which, the EMC requirements of monitoring device for converter valve are proposed.
Research on Topology and Parameter Design of a Novel Flexible On-Load Voltage Regulator
Authors: Han Li-bo , Yin Jing-yuan , Sun Long-fei , Wu Li-xin , Wei Tong-zhen 
Published: December 2022

Abstract
Traditional on-load tap charger (OLTC) transformer use mechanical switch or anti-parallel thyristor as on-load tap changers. By changing the position of the tap chargers, the transformation ratio is changed, so as to achieve discrete step voltage regulation function. In this paper a novel Flexible On-Load Voltage Regulator (Flexible OLVR) is proposed, which is integrated design of Power Electronic Converter (PEC) and OLTC transformer. The converter is set at the primary side of the transformer, and it could control the output voltage accurately to relize the stepless voltage regulation when there is grid voltage fluctuation. The topology and operating principle of 10kV/0.4kV Flexible OLVR are given in this paper. Secondly, the main parameter design criteria is discussed through a group of design examples. Finally, the feasibility of the scheme is verified by the simulation waveform.
Research on adjustable load dividend transmission strategy under aggregate operation mode
Authors: Zhang Lu , He Ping , Zhang Xiaoli , Hou Xuzhe , Chen Simin , Li Shuling , Liu Dunnan 
Published: December 2022

Abstract
In recent years, the scale of inter-provincial and inter-regional power transmission keeps growing, the proportion of new energy keeps rising, and the complexity of power grid structure increases the risk of its operation control. Under the aggregation operation mode, the adjustable load has great electricity elasticity. Guiding its electricity consumption behavior and making it participate in the power grid regulation operation can greatly improve the safety of operation, promote the absorption of new energy and realize the optimal allocation of power resources. This paper studies the form of adjustable load participation in grid regulation in different scenarios under the aggregate operation mode, analyzes the cost and benefit of adjustable load participation in electricity market transactions, and then combines the evaluation method based on the contribution of adjustable load users in different scenarios to propose a dividend transmission strategy of adjustable load in the aggregate operation mode.
Source Load Interval Coordinated Scheduling of New Energy Grid with Load Fluctuation
Authors: Luo Guoming , Chen Xiaotong , Zhou Bo 
Published: December 2022

Abstract
In order to reduce the impact of load fluctuation brought by new energy interconnection, the operation cost of power grid is increased. Considering the characteristics of load fluctuation, this paper studies a new energy grid source load interval coordination scheduling method. Based on the characteristics of source load fluctuation and demand side load fluctuation of new energy grid, the dispatching principle is established. In this paper, the flexible operation region of new energy grid is calculated, and the target function of power grid source load interval is constructed. Numerical results show that the proposed method can improve the economy of energy storage unit and power system, and the comprehensive benefit is positive in different scenarios.
Research and application of energy supply and demand allocation method for rural differentiation
Authors: Liu Yanqing , Li Yuanfu , Li Xuehua , Liu Wenlin , Xu Zhigen , Zhang Jianling 
Published: December 2022

Abstract
China is a vast country with complex and diverse energy, economy, society, culture and natural geography. Due to the great differences in geographical location, degree of development and resource endowment, the rural energy consumption scene is complex and changeable, and the energy structure configuration has problems such as single scene, poor flexibility and applicability. Therefore, this paper first puts forward the development scenario of rural energy differentiation; Then, based on the classification of rural energy development differentiation scenarios, a multi-objective planning weight allocation model is established for the three goals of economy, environmental protection and energy conservation when the system is running; Finally, in order to verify the superiority of this model, three typical rural areas are selected for verification, and the flexible and adaptive rural comprehensive energy optimal allocation results of the travel alienation scenario are obtained respectively. The simulation results show that the optimal allocation method can achieve the purpose of adapting different target weights through scene differences to configure the equipment capacity of rural integrated energy system, so as to meet the purpose of rural energy supply and demand allocation in differentiated scenes, and better achieve economy, environmental protection and energy conservation.
Design of Fin Stabilizer Controller Based on Fuzzy Control Principle
Authors: Jiang Lu 
Published: December 2022

Abstract
As the ship is sailing in the sea, the PID control parameters set may not be the optimal parameters under different sea conditions according to the changes of sea conditions and wind, waves and currents, so the PID control of fin stabilizer cannot achieve the ideal control effect in the actual ship operation process. This paper studies the design of fuzzy controller with better robustness than traditional PID control, and explores the actual control performance of fuzzy controller under different sea conditions.
Thermal Analysis and Test of Axial Flux Permanent Magnet Synchronous Motor Performances
Authors: Dou Haishi , Zhang Youtong 
Published: December 2022

Abstract
The axial flux permanent-magnet synchronous motor with amorphous alloy stators has the advantages of high power density, high efficiency, large starting torque. But the PMSM has poor performance in heat resistant and radiation. And the electromagnetic loss has a significant impact on in-wheel motor’s heat generation. To demonstrate the influence of electromagnetic loss on winding coils of the PMSM, the mathematical model of the thermal transformation was founded to illustrate the progress of temperature rising. The mathematical model and experimental test were verified mutually. The experimental prototype was manufactured and tested, including the output power model and braking energy recovery model. And the experimental prototype performed working in low rotation speed mode and middle rotation speed mode separately, when the revolving speed increased by 50% the thermal of winding raise approximately 23.5%. Further, the analytic formulas and experimental results consistent with each other approximately, in which the mathematical analysis method was verified by test value.
Analysis of commutation current fluctuation of saddle shaped secondary helical coil electromagnetic launcher
Authors: Sun Yikang , Ma Bendong , Wang Jianchao , Sun Zhiqiang , Wang Housheng 
Published: December 2022

Abstract
The saddle shaped secondary helical coil electromagnetic launcher, which has the advantage of long-distance propulsion is improved on the basis of helical coil electromagnetic launcher (HEML). However, the current fluctuation of the system is the same as that of the traditional helical coil electromagnetic launcher, and current fluctuation can cause thrust fluctuation and commutation arc problems. Therefore, it is particularly important to analyse the commutation current fluctuation of the saddle shaped secondary HEML. In this paper, the commutation process of HEML is analysed in detail by analogy with the commutation process of DC series excited rotating motor. Then the system model is built in ANSYS/Maxwell, and the excitation circuit is built with Simplorer to jointly simulate the system. The reason of commutation current fluctuation is analysed by using the principle of flux continuity, and the correctness of the principle of flux continuity is verified by analysing and calculating the simulation datas. It has a good guiding significance for the subsequent improvement of thrust fluctuation and commutation arc.
Research on Defects of High Voltage Cable Fusion Joint Using XLPE Insulation Material
Authors: Yu Ting , Liu Sanwei , Duan Xiaoli , Zhong Cheng , Duan Jianjia , Zeng Zeyu , Zhang Daoyuan 
Published: December 2022

Abstract
High-voltage cable fusion joints are made on site. Affected by environmental conditions, fusion joints are prone to small defects that are not easy to find, resulting in frequent accidents after the joints are put into operation. There is currently no effective method to detect small defects inside the joint. Therefore, this paper proposes to use digital radiography nondestructive test technology to detect the main insulation and conductor recovery process of high-voltage cable fusion joints. The results show that the digital radiography nondestructive test method can effectively find defects such as microporous bubbles, conductor bending, and eccentricity in the main insulation of XLPE fusion joints. The on-site anatomy demonstrates the accuracy of the test results, and the digital radiography nondestructive test can effectively detect the defects of high-voltage cable fusion joints. Experiments have verified that the decrease of cross-linked pipe temperature and nitrogen pressure can lead to the generation of microporous bubbles in the XLPE main insulation. For conductor bending and eccentricity defects, the limit value of the welding conductor bending gap is 11mm through simulation calculation.
Analysis of monitoring effect on Hybrid Electric Field for AC/DC Cross Line
Authors: Yang Yi , Ma Xue-kai Si , Fang Shu-bo , Han Qing , Zhou Zan-dong 
Published: December 2022

Abstract
Electrostatic induction charge which generated by the coupling effect of hybrid electric field of AC/DC cross line and metal object under the transmission line can cause different levels of electric shock injury to human. In order to find out the distribution law of the hybrid electric field and reduce the effect of electrostatic induction, this paper set up shielding lines which paralleled to the AC and DC lines respectively on the outside of the side conductors and along the diagonal of parallelogram at crossing point, then measured the electric field distribution in shielding areas of 750kV AC and 500kV DC lines and the induced voltages of shielding lines in different states, analyzed the effect of shielding line on power frequency electric field and DC composite electric field. The results showed that shielding lines have a reducing effect on the hybrid electric field of the cross lines, the average power frequency field strength is reduced by 12.6%, the DC composite field and power frequency electric field at the crossing position was far less than the limits specified in the respective standards. Both induced voltage of bare lines and shielding lines wrapped with adhesive tape increase with the raise of erection height. Under the same conditions, the average induction voltage of bare conductor is 9.3% higher than that of shielding lines wrapped with adhesive tape. There is no obvious difference between parallel and vertical erection methods of the same number of shielding lines in the degree of reduction of induced voltage.
Research on offshore DC wind power circuit
Authors: Jia Moqi 
Published: December 2022

Abstract
This paper studies the offshore DC wind power technology, to explore how to reasonably transmit and use the electrical energy generated by the offshore wind generator, to obtain a more optimized circuit model of offshore DC wind power technology. This paper mainly discusses the process of voltage conversion, inverter, rectification and output of appropriate three-phase AC voltage in the process of ac transmission from HVDC offshore wind turbine. According to the “π” equivalent circuit principle, the paper compares HVDC transmission mode with HVDC transmission mode, and compares the harmonic distortion rate of unipolar modulation and bipolar modulation in pulse width modulation through analog circuit, determines the final circuit model and obtains the simulation result diagram.
Development and functional design of the test device for induced voltage in distribution network lines
Authors: Li Fengshuo , Cao Huaming , Wang Xiaoning , Sun Mingxing , Jin Along , Li Guanglei 
Published: December 2022

Abstract
In order to measure the induced voltage of the suspended conductor under the high-voltage transmission line, a portable floating potential measuring device is developed in this paper. This paper proposes a design scheme and develops a high-precision induced voltage sensing and detection module to ensure its sensitivity and accuracy. In order to improve the anti-interference performance, a high-voltage isolation and protection circuit is designed to ensure the anti-interference performance of the system in the strong electromagnetic environment. Finally, the coupling and data acquisition system of multi-physical sensors was developed, and field tests were carried out on site. The test results verify the feasibility of the proposed technical scheme, and the experimental error meets the expected goal.
Microstructures of Graphene applied as Electrode Materials in Lithium-ion Batteries
Authors: Ji Zimo 
Published: December 2022

Abstract
With the dramatic increase in the consumption of electric energy, lithium-ion batteries (LIBs) become one of the most important devices for energy storage. Among various types of electrode materials in LIBs, graphene is one of the potential alternations due to the outstanding conductivity and ability of ions storage. But the limitation of capacity and stability brings challenges when applying graphene in LIBs directly. Recently, the microstructure of graphene is focused more to improve the performances of LIBs furtherly. Several kinds of microstructure in graphene have been designed including three-dimensional (3D) microstructure, core-shell microstructure, sandwich microstructure, and porous microstructure. This review aims to summarize the designs of these microstructures, conclude the effect of each microstructure and provide suggestions for future development.
A Review on Hydrometallurgy of Typical Lithium-ion Batteries
Authors: Chen Xizi 
Published: December 2022

Abstract
The development of electronic products and electric vehicles (EVs) gives a burgeoning demand for lithium-ion batteries (LIBs). Such a large amount of LIBs challenges the protection of environment and supply of raw materials. On one hand, spent LIBs contain toxic and harmful substances, causing serious pollution. On the other hand, spent LIBs contains a lot of critical metals, which can be used as an important secondary resource to alleviate the shortage of raw material supply of LIBs to a certain extent. Therefore, the recycling of spent LIBs is imperative. In the recycling process, hydrometallurgical process has been widely used because of its high product purity and low air pollution. The current research status of hydrometallurgical processes for lithium iron phosphate battery (LFP) and lithium nickel manganese cobalt oxide battery (NCM) was reviewed in this paper. The characteristics of different treatment technologies are analyzed. Finally, the prospect and development direction of recycling of lithium-ion batteries are given.
Research on state assessment method of subway 35kv switchgear based on multi-feature quantities
Authors: Han Longfei , Zhang Xiaohong , Chen Yuting 
Published: December 2022

Abstract
The health status of 35kv switchgear directly affects the safe operation of subway. In view of the current problems of single feature quantity, inadequate detection elements and inaccurate overall state evaluation of switch gear, a state evaluation method for metro 35kv switch gear based on multi-feature quantity was proposed. The characteristic parameters such as transient ground voltage, ultrasonic value, cable joint temperature and bus temperature were determined by triangular fuzzy number method with constant weight. The variable weight method was introduced to ensure the balance of state evaluation, and the state evaluation of switch cabinet was carried out with matter-element extenics. The actual detection data of 35kv switchgear 8DA10 in a Shanghai metro substation is taken as an example to verify the effectiveness of the algorithm.
The optimization method for park load active aggregation according to flexibility and relevancetion
Authors: Ji Degui , Liang Peng , Liu Yang , Wang Chong , Wang Zhuo , Gao Mingze , Bian Zhenwei 
Published: December 2022

Abstract
For the flexibility of Park load, a degree of positive and negative coupling between different loads is considered. And an active aggregation optimization method of park load is proposed based on flexibility and correlation degree. According to the scenario data of historical demand response, an optimization model is build, and a certain number of aggregates meeting the demand response scenarios are formed by active aggregation to guide the scheduling of daily operation periods. Through the optimization results, not only the optimal polymer is obtained, but also a certain number of standby polymers is obtained. While completing the response indicators issued by the power grid, the flexibility and relevance of the load in each park are fully applied to reduce the calculation scale of daily operation scheduling.
Research on fuzzy control strategy of PMSM electric braking considering state constraints
Authors: Wang Hui , Gong JiaPeng , Dong XingYan , Gao Feng , Luo ZhiWei 
Published: December 2022

Abstract
The PMSM drive system is widely used in new energy vehicles, and the rational design of the electric braking control strategy can maximize the recovery of energy during the braking process of the vehicle and improve the energy utilization rate of the vehicle. This paper firstly analyzes the energy system architecture of PMSM driving electric vehicle. Then the braking range, braking intensity and vehicle speed are classified and the braking intention is accurately identified based on the fuzzy control strategy. And, the braking strategy is modified by considering the braking constraints of the PMSM and the state constraints of the power battery. Finally, a test platform is built to verify the designed control strategy under six typical braking conditions.
The test method of the thunder and lightning direct effect protection equipment
Authors: Li Jianyi , Jin Lu 
Published: December 2022

Abstract
In order to avoid the harm caused by the direct effect of lightning, modern new ships are equipped with lightning direct effect protection devices. However, due to the harsh environment such as high temperature, high humidity and high salt, it is easy to change its performance indicators and affect the lightning protection effect. Taking the direct lightning protection device with gaps installed at the rear end of the ship antenna as an example, through the study of its working principle and main technical indicators, the items that need to be tested regularly are determined, and the corresponding test methods are formulated. Through a large number of experiments and test data verification, the conclusion that the method can effectively reflect the main technical indicators of lightning protection facilities and then effectively evaluate the protection effect of lightning protection facilities is drawn. The research results of this paper are of great significance to regularly test the lightning direct effect protection equipment, accurately grasp the changes of its technical performance indicators, and ensure the protection effect of lightning direct effect.
Design and Research of Protection and Action Characteristic Test Device
Authors: Li Zhong-kui 
Published: December 2022

Abstract
Before and after the EMC immunity test, it is necessary to verify whether the main performance indicators of the tested equipment are reduced. The protection and action characteristics test device is the equipment to verify the main performance indicators of mining electrical switches and motors. Its research and development involves a variety of equipment to cooperate to realize its system functions. However, there is no single manufacturer in the market to produce such equipment or system, which needs independent research and development according to the needs of the electrical equipment tested in the laboratory. The protection and action characteristic test device is applied to the mechanical characteristic test of high-voltage switch. It can be used as the test equipment for high-voltage and low-voltage leakage action value and time test, as well as the leakage current and capacitive current compensation efficiency test. It can also be used for the characteristic test of the test device, overcurrent protection characteristic test and other test items.