bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and optical parameters of polyvinyl alcohol films reinforced with Mn2O3/reduced graphene oxide composite
Authors: Soliman T S , Vshivkov S A , Abdel-Salam Ahmed I , Gomaa Islam , Khalid A
Published: December 2022

The novel polyvinyl alcohol (PVA) films reinforced with varied concentrations of Mn2O3/reduced graphene oxide (rGO) nanoparticles (NP) are prepared via the casting technique. A hydrothermal approach methodology is used to prepare manganese oxide reduce graphene oxide (Mn2O3/rGO) composite. The X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), and optical microscope setups are used to study the impact of nanoparticles on the structure of the PVA matrix. The surface roughness was measured and found to increase with increasing NPs concentration in the polymer matrix. The UV–vis spectroscopy is used to investigate the optical absorption and transmission data for the prepared films. The addition of Mn2O3/rGO NP in the polymer matrix effects on the optical parameters like the absorption coefficient, optical bandgap, refractive index, and optical conductivity. The optical bandgap of PVA films with Mn2O3/rGO NP is lower than that of PVA pure. The refractive index and optical conductivity were tuned with the addition of Mn2O3/rGO NP. The PVA-Mn2O3/rGO films are promising material for various opto-electronic fields.
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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Multi-energy coordination control method of power system connected to microgrid of combined cooling, heating and power
Authors: Qi Han , Chen Kai , Liu Yanmin , He Xinan
Published: December 2022

The problems of energy shortage and ecological destruction are becoming increasingly serious. As a comprehensive energy utilization system, cogeneration system has gradually become a research hotspot. In order to improve the basic frequency stability and reduce the operation cost, this paper presents a multi-energy coordinated control method for CHP micro-grid. Firstly, the topology of CCHP system is analyzed. On this basis, this paper constructs a CCHP power system including micro turbine (MT) and air conditioning (AC). Secondly, a multi-component composite energy storage method for power system is proposed. Different types of energy storage devices than a single way of energy storage has better performance, to achieve multi-complementary. Finally, in the construction of power system collaborative control model, this paper constructs power system collaborative control model based on load storage optimization idea of source network. Experimental results show that the proposed control method has strong fundamental frequency stability and low operating cost, and has certain application value.
Design of measuring circuit of motor speed based on Proteus
Authors: Yue Chenyang , Zhao Yiquan , Zhang Peng , Yang Chengkai , Li Jianhui , Sun Yanzhe
Published: December 2022

In this paper, 51 single chip microcomputer, photosensitive element and 1602 are used to design the motor speed measurement circuit based on grating method, and Proteus software is used to build the circuit and function verification. Finally the project achieves the motor speed measurement and adaptive content display under different precision, the project simulation verification results are well. At the same time, on this basis the construction of motor speed measurement circuit is discussed and promoted.
A method for estimating line industrial frequency parameters based on wideband information
Authors: Dong Fangfang , Chen Fang , Guo Quan , Lu Wei , Wang Jilei , Sun Qingbin
Published: December 2022

Accurate acquisition of transmission line parameters is the basis for grid condition monitoring and data analysis, which is of great significance for the safe and economic operation of the grid. With the widespread use of phasor measurement unit (PMU) technology, the wideband information in the grid can be exploited, which broadens the new direction for line parameter identification. In this paper, a method is proposed to identify line frequency parameters based on wideband information. A mathematical model for line parameter identification with wideband information is established, and the identification of line frequency parameters is achieved by iterative solution through least squares. The results show that the accuracy of the parameter identification is improved by adding wideband information, and the identification of industrial frequency parameters for lightly loaded lines can be achieved. Finally, the feasibility and correctness of the method is verified by simulation.
Technology of One-phase-to-earth Trouble Section Location Based on Prony Decomposition and Multi-constituents Fusion
Authors: Li Xinming , Chen Yanxia , Wang Zhiyong , Xu Wanyu , Xu Jiyang , Liu Wei , Zhang Jiliang
Published: December 2022

Prony method is used to fit multi-constituent data through a series of linear combinations to obtain the amplitude, phase, damping factor and frequency of each constituent. Prony decomposition is used to decompose the temporary constituents of null sequence current to multi terminal trouble in dispersion network. The DC constituent and high-frequency constituent of trouble null sequence are effectively extracted and fused. The cutting position is obtained with comparing the phase relationship to the orientation information of the fused constituent. Theoretical analysis and results show that the algorithm is applicable to all kinds of ground connection errors, can accurately and reliably determine the one-phase ground connection error pause of dispersion network, and effectively improves the positioning accuracy and efficiency.
One-Phase Ground Fault Line Selection Technology for Distribution Network Based on Comprehensive Analysis of Phase Current
Authors: Zhang Xinyu , Wang Yang , Du Wei , Wang Zhibo , Li Haifeng , Gu Taiyu
Published: December 2022

Due to the various types and different characteristics of one line-to-ground faults occurring in the partial network which is responsible for distribution, the adaptability of location technology applicable to a one fault type is poor. To ensure the operational reliability of the partial network which is responsible for distribution, this thesis shows a one-phase ground fault line selection technology for distribution networks that is applicable to various types of faults. By using this technology, we can comprehensively analyze the characteristics of phase current in transient state and steady state when different types of faults occur, and fault line selection algorithms suitable for intermittent arcing and resistance grounding respectively were proposed according to the steady-state phase and transient mutation characteristics of phase current. In addition, the feasible region of the proposed line selection technology was expanded by using the comprehensive analysis algorithm combined with two-line selection algorithms, which ensures the reliability of selecting fault line after different types of one line-to-ground fault s occur in the system. Finally, the ATP simulation software was used to verify the reliability and engineering applicability of this technology.
Power system short-term load forecasting based on BP neural network
Authors: Wang Xue
Published: December 2022

Electric energy plays an important role in the development of national industries. Based on the characteristics of China’s electricity load, this paper uses the signal decomposition of BP neural network, deep learning neural network and intelligent optimization basis to conduct research on short-term electricity load forecasting of Chinese national electricity consumption.
A Frequency Measurement Method for Protection of Smart Circuit-breaker
Authors: Ren Zhendong , Zheng Libin , Zhou Ying
Published: December 2022

The application scale of new energy such as wind energy and solar energy in China is increasingly large. One of the characteristics of these energy sources is instability. Circuit-breakers play an important role protection in distributing these energy sources. Aiming at a new type of smart circuit-breaker architecture, this paper proposes a frequency measurement method for protection function, that is, the waveform sample value of high precision and high sample rate output by the DMA of the metering chip. The FIR filter is used to eliminate harmonic interference, impulse interference, etc of sample value. The frequency value is calculated by the interval duration between the two cross-zero points of sample value, and the simulation process, as well as the results, are given.
Parallel Combined Spread Spectrum Error Analysis And Succesive Error Correction Method
Authors: Wang Zhi-qiang , Ding Dan , Tang Peng-yu
Published: December 2022

Traditional spread spectrum techniques provide a strong anti-interference capability but a relatively low transmission rate. This is addressed by the parallel combination spread spectrum technique which provides higher transmission efficiency, security, and spread gain. Nevertheless, the receiver of a parallel combined spread spectrum system requires to distinguish multiple spread spectrum sequences. Therefore, any reception errors are propagated in the receiver hence leading to a larger number of errors. Moreover, spread spectrum sequences with different mode values experience different probability of errors at the receiver. The existing analysis of the error location in the parallel combined spread spectrum is only an estimate after countless experiments. In this paper, we theoretically analyze the probability of correct discrimination of parallel combination spread spectrum with different modulus values. Furthermore, according to the probability analysis of correct discrimination therefore the parallel combination spread spectrum is improved. This significantly reduces the bit error rate of the system and improves the reliability only with a slight degradation of transmission efficiency.
Load modeling of different type intelligent building considering thermal effect and dynamic electricity price
Authors: Tang Junci , Ge Yanfeng , He Huan , Cui Dai , Cui Jia , Xu Kun , Hu Zhen
Published: December 2022

In this paper, the intelligent building model is firstly established. And, the characteristics of battery in electric energy storage are compared. The distributed renewable energy is applied to the intelligent building. Secondly, considering the intelligent building load modeling under the influence of heat effect and dynamic electricity price mechanism, the intelligent building load modeling is analyzed. It adopts the verification generation modeling based on multiple constraints to make the modeling more accurate. Thirdly, the advantages of the algorithm are verified through the calculation example analysis. Finally, The modeling accuracy of commercial building is improved by 3.8%.
Industrial load identification based on sparse representation classification
Authors: Liu Meijie , Meng Zhen , Qiu Peng , Zhang Yan , Gao Mingze , Han Ni , Li ZhiMin
Published: December 2022

In this paper, sparse representation classification (SRC) model based on discriminant dictionary is proposed to train loads of different categories by K-SVD algorithm. Firstly, The absolute value of sparse coefficient and the category of atoms are used to determine the load category. Secondly, the identification of load types is improved in the traditional SRC method based on dictionary learning. Thirdly, the actual identify effect is optimized. Finally, an example is given to illustrate the recognition process. The discriminant dictionary-based SRC method is compared with the traditional SRC method. It proved the feasibility and effectiveness of the method.
Single-phase Grounding Fault Section Locating Technology for Distribution Network Based on Rough Set Algorithm
Authors: Zhang Xinyu , Wang Yang , Du Wei , Li Haifeng , Wang Zhibo , Gu Taiyu
Published: December 2022

With the continuous development of distribution networks, the proportion of the power electronic equipment that accesses distribution networks is increasing, which increases the system capacitance current, making the probability of single-phase grounding fault via intermittent arc in the system significantly increased. However, most traditional locating technologies are suitable for single grounding fault type via stable resistance, and cannot locate the fault above, which seriously impairs the reliability of the power supply of distribution networks. In order to solve the problem above, this paper puts forward the single-phase grounding fault section locating technology for the distribution network based on a rough set algorithm. This technology is able to obtain the phase current signals in the system for judgment, and analyze multiple characteristics of current signals with a rough set algorithm, thus determining the fault types in the system correctly. Moreover, it is also able to determine fault sections with proper section locating algorithms based on different fault types. Furthermore, it is able to locate sections of various fault types, such as resistance fault and fault via intermittent arc, with an expanded feasible region. Besides, it only makes a judgment based on phase current without collecting the zero-sequence voltage of the system, ensuring adaptability. Additionally, it is able to supplement and optimize fault type identification categories by adding condition attributes of fault characteristic analysis in the rough set algorithm, having certain engineering application values. In the end, the feasibility of this locating technology was verified with ATP power system simulation software.
Demagnetization Fault Diagnosis of Magnetic Coupler Based on STFT-S
Authors: Liu Luping , Sun Jianzhong
Published: December 2022

Magnetic coupler (MC) has been widely used in petroleum, chemistry and other industrial fields. However, demagnetization faults are easy to occur in permanent magnets when transporting high-temperature media. Demagnetization faults are difficult to detect due to the double-rotor structure of MC. To solve this problem, a demagnetization fault detection device for MC is established, and a short time Fourier transform method based on speed window function (STFT-S) is proposed. The demagnetization degree and fault pole location of MC under nonstationary conditions of velocity is determined by analysing the time-frequency characteristics of the STFT-S transform. Finally, the finite element simulation results verify the effectiveness of the proposed method.
Analysis of Power Load Characteristics Based on Adaptive Ensemble Clustering Algorithm
Authors: Luo Liqin , Zhu Chenxuan , Wang Chaowei , Long Yanhua
Published: December 2022

With the growing number of power users and more flexible power consumption, how to cluster the power load curves efficiently becomes particularly important. In order to improve the accuracy, effectiveness and rapidity of load clustering, an adaptive integrated fuzzy clustering algorithm was proposed in this paper. Firstly, the initial clustering centroids were obtained by the improved DPC algorithm; then, under the dual guarantee of Euclidean distance and membership, FCM algorithm was used to cluster load curves; finally, the optimal number of clusters was obtained by the improved adaptive method in the iterative process; thus, the autonomous and accurate clustering of power load curve was realized. The proposed algorithm, DPC algorithm and FCM algorithm were applied to the load clustering experiment of power system respectively. The comparative analysis shows that this algorithm is effective and superior for load curve clustering.
A two-tier game model based scheduling strategy for Virtual Power Plants
Authors: Zuo Juan , Wang WenBo , Hou XiangMin
Published: December 2022

Recently, there has been a lot of attention on how to enhance the management capabilities of distributed electricity production and demand aggregation by Virtual Power Plants (VPPs), which poses the challenge of leveraging their ability to participate in electricity markets to maximize operating profits. This paper analyzes the scheduling problem in fully distributed controlled VPP and proposes a two-level game model. In this model, the Stackelberg game is used to describe the interaction between Distributed Energy Resources (DER) and Energy Management System (EMS). On the other hand, the competition between DERs is formulated by the Cournot game. EMS sets its electric rate as single-leader, and DERs generate the optimal generation capacity accordingly as multi-follower. Then, we analyze and obtain the relationship between the demand and the resource supply to achieve market equilibrium on maximizing the utility of EMS and DERs. Simulation results show the analysis’s correctness and the proposed strategies’ performance improvement.
Intelligent Orchestration Algorithm for Power Backbone Optical Network with Service QoS Awareness
Authors: Liang Wenjuan , Liang Yutu , Zhu Wenhong , Deng Xiaozhi
Published: December 2022

The power backbone optical network has the shortcomings of low spectrum utilization, and high service blocking rate, which cannot satisfy the differentiated quality of service (QoS) demands of the power services. This paper proposed a power backbone optical network architecture that uses elastic optical networks (EONs) to improve frequency utilization, and proposes an upper confidence bound (UCB)-based intelligent orchestration algorithm for power backbone optical network. Simulation verified that the proposed intelligent orchestration algorithm can improve the performance of the intelligent bandwidth allocation and meet the requirements of differentiated QoS demands.
Study of the effect of treatment with non-equilibrium low-temperature plasma on the hygienic properties of lining leathers for shoe with genuine leather upper
Authors: Tikhonova N V , Zhukovskaya T V
Published: December 2022

the shoe grade is determined by the quality of the materials that make up the product package. Natural lining leathers for shoe with genuine leather upper should differ primarily by high moisture and vapor exchange properties to ensure an optimal microclimate of the inside of the shoe space. In the paper the application possibility of treatment of lining leathers for shoe with genuine leather upper with non-equilibrium low-temperature plasma to obtain a material with improved hygienic characteristics is justified. Because the operating conditions of lining materials for shoe with genuine leather upper are more determined by the process of contact with the surface of the foot than by environmental effect. Thus, the quality of lining materials for shoe with genuine leather upper is determined primarily by compliance with hygienic requirements, among which vapor and air permeability, hygroscopicity; resistance to sweat. In the study it was revealed that because of the treatment with NLTP HFC discharge of pigskin leathers, there is an increase in the parameter values of hygroscopicity by 34%, moisture-yielding capacity by 36%, vapor permeability by 38%, air permeability by 27%, the capacity to absorb sweat vapor by 33% and the capacity to exude sweat vapor by 42%. Consequently, the treatment with NLTP HFC discharge of pigskin leathers for shoe lining with genuine leather upper makes it possible to improve their quality by sequencing their structure, which in turn acts to increase the efficiency and intensity of moisture interchange processes between the material and the environment of the inside of the shoe space, increases the comfort of the latter and prevents potential adverse effect on human well-being.
Effect of Low-Temperature Plasma Treatment on The Properties of a Complex Wool-Containing Material
Authors: Fatkullina R R , Yarullin R M , Abutalipova L N , Khadysov B A
Published: December 2022

The article investigates a layer of felt in a complex material, which we intend as rehabilitation footwear element. The complex material consists of layers of rubber and felt, connected with polyurethane adhesive, and we design it for the manufacture of shoe-product sole. The layer of felt inside is in contact with the foot and serves as an insole. The felt was treated with low-temperature plasma (LTP) from the inside of the complex material. It was experimentally obtained the wettability index: for the complex material, containing a treated layer of felt, and a control untreated felt. The research obtained an increase in the hydrophilicity of the LTP-treated felt, which is explained by degreasing the surface, an increase in the porosity of the non-woven material «felt», as well as structural changes in the wool fiber due to plasma treatment. Plasma treatment of woolen felt layer can be recommended to increase the hydrophilicity of the surface and impart antibacterial properties to the inner («insole») surface of the complex material by applying infusions of medicinal plants, etc.
Simulation of the mixing process in a slot channel with jet injection
Authors: Kurbangaleev A A , Battalov A F , Kh Tazyukov F
Published: December 2022

The article presents the results of modeling in a two-dimensional formulation of the hydrodynamic process of mixing two streams of Newtonian fluids in a channel with jet injection. The mixing process takes place in a turbulent flow mode, without chemical and thermal interaction. The article considers the flow of a mixture in a flat slit channel when mixing two liquids. The first component of the mixture flows through the main wide channel. At a distance of 50 mm from the point of entry into the channel perpendicular to the main channel, there is a radial jet nozzle with a width of 1 mm, through which the second component enters the mixing channel. The article discusses several problems with different initial mixing rates of components. The characteristics corresponding to water and ethyl alcohol were taken as test components for mixing liquids. The simulation was carried out in the ANSYS-Fluent software package. The purpose of this work is to study the process of mixing two liquids in a slit channel. The article presents the results of modelling the mixing process.
Plasma modification physical and mechanical properties of nonwoven materials of medical masks
Authors: Azanova A A , Yu Galimzyanova R , Abutalipova L N , Khisamiyeva L G
Published: December 2022

The paper considers the influence of plasma flow of a high-frequency capacitive discharge at reduced pressure (as a potential sterilization tool) on the main physical and mechanical characteristics of a three-layer medical mask (spunbond-meltblown-spunbond). The treatment was carried out using argon and air as plasma-forming gases. It is shown that the breathability of the mask determines (limits) the breathability of the middle layer (meltblown). Plasma treatment in the modes under consideration does not significantly affect the air permeability and mechanical tensile strength of the composite layers of the mask. There is a slight increase in vapor permeability, an increase in the hygroscopic properties of the middle and inner layers, which indicates an improvement in the hygienic characteristics of the mask, but at the same time, the hydrophobicity of the outer layer is preserved. When plasma is used to sterilize medical masks, bacterial filtration efficiency and microbiological purity will be the main deciding factor.
Modification of the surface of nanostructured Bi0.95La0.05FeO3 ceramic by plasma
Authors: Gadzhimagomedov S. Kh. , Alikhanov N.M.-R. , Rabadanova A.E. , Emirov R.M. , Palchaev D.K. , Murlieva J. Kh. , Gadzhiev M. Kh. , Saypulaev P.M. , Ilyichev M.V.
Published: December 2022

Nanostructured ceramics of the composition Bi0.95La0.05FeO3 were fabricated, and the structure was studied before and after exposure to an argon plasma flow at a temperature of ∼ 600 °C for ∼ 30 minutes. Plasma treatment of the surface, with a positive effect of the formation of a monolithically conjugated structure and an increase in the size of grain crystallites, leads to a decrease in the proportion of the main phase on the surface to ∼70%. It has been established that compaction is up to ∼30% of the sample thickness.