bluuebunny/crossref_metadata_2025 huggingface dataset:
Vehicle re-identification method based on global and local feature fusion
Authors: Bing Zhou , Wei Wei , Huaihong Wu
Published: August 2021

Vehicle re-identification is still an issue worth discussing due to change of view, light and angle changes. At present, the key of vehicle reidentification research is to solve the problems that the difference between the same class is big and the difference between different classes is small. For the study, a vehicle re-identification method ground on view classification is proposed.The vehicle images are divided into four views, namely, front, rear, top and side, and local features are extracted by the segmented view information. Using the CNN feature extractor, the global feature representation with car ID attribute is learned. We have done experiments with the VERI-776 data sets. The mean average accuracy of 78.13% is obtained, which proves the effectiveness of the method.
A service caching method for mobile edge computing
Authors: Wu Xiaojun , Wang Yong , Yuan Sheng , Xie Peiru
Published: August 2021

Mobile Edge Computing (MEC) is considered as a key technology to support 5G networks. It can push cloud computing functions to the edge of the network, and achieve the purpose of reducing latency and reducing energy consumption through computing offloading and edge caching. In the MEC system, by caching computing services from the cloud center to the network edge, MEC can provide users with more services, and also be able to make greater use of network resources and improve system performance. However, which services to cache at edge nodes and how to cache these services have become an important challenge of the research. In order to solve the aforementioned problems, in this paper, we analyze the popularity of each cached object firstly, and propose a novel service caching algorithm, which aims to reduce system delay and improve resource utilization. In addition, we design a novel cache replacement algorithm that successfully predict future requests by analyzing historical data, thereby greatly improves the cache hit rate. Finally, experiments prove that our algorithms have greatly improved system performance and hit rate.
Application of Improved S-Curve Flexible Acceleration and Deceleration Algorithm in Smart Live Working Robot
Authors: Wu Han , Huang Jianye , Lin Shuang , Liu Bingqian , Fan Yuanliang , Wu Binyu , Huang Zhifan
Published: August 2021

Smart live working robot incorporates the merits of security and reliability, which can greatly improve automation rate of living working, suitable for power distribution network live working applications. Due to flexible strike and shake in automatic stripping wire module of smart live working robot start and end period, an improved S-curve flexible acceleration and deceleration control method is proposed. Based on analyzing disadvantage of conventional linear and exponential acceleration and deceleration algorithm, formula math model of improved cubic polynomial S-curve acceleration and deceleration algorithm is derived. Five-paragraph format motion planning is adopted the proposed S-curve control method, which can realize appointed acceleration and deceleration time moving. Meanwhile, the acceleration is continuous during moving period, and according to different working condition, different Scurve type can be chose. The simulation and practical operating results showed that proposed control strategy can effectively reduce flexible strike, thus improving stationarity and accuracy of the control system.
Research on optimization of improved ant colony algorithm in the temperature control process of cold creep forming
Authors: Xu Yiming , Liu Naijia , Xue Peng
Published: August 2021

In the process of cold creep forming, the temperature control has problems such as low accuracy and slow response speed. Moreover, the conventional PID temperature controller has poor anti-interference ability and low control accuracy.This paper designs a PID control strategy based on improved ant colony algorithm which is applied to the temperature control of cold creep forming. With the help of Matlab simulation software, a temperature controller simulation model is established, and certain improvements are made to the model on the basis of the traditional ant colony algorithm, applying to search for the optimal parameter combination in PID control. The simulation results show that the designed control strategy can find a better parameter combination than the PID control of the ant colony algorithm. Therefore, the application of this control method to the cold creep forming temperature control system can effectively improve the product quality and production efficiency of the cold creep forming process.
Detection of Abnormal Hot Spots Infrared Images of Power Equipment Based on YOLOv4
Authors: Qi Xiao , Shi Lei , Li Lei , Chai Fangsen , Han Dongxu , Zhang Chong
Published: August 2021

The stable operation of power equipment is very important to ensure the stability of power grid. In this paper, an object detection model is designed for detection of the abnormal hot spots of electrical equipment. In order to improve the performance of the object detection model, data augmentation of image is applied to extending the training set. The test results show that the model based on YOLOv4 can identify and locate the abnormal heating fault point in the infrared image with high accuracy. The precision and recall rate of the object detection model on test set can reach 88.51% and 91.66% respectively.
Energy and economic evaluation of Gas-electric hybrid energy system based on improved genetic algorithm
Authors: Ce Liang , Yinke Dou , Yuchen Wang
Published: August 2021

In the future when there are more and more new energy sources in the grid, the Power-to-Gas(P2G) interconnected operation network will be affected by new external energy sources, resulting in an imbalance between the generated power and the actual power required for the normal operation of the grid. On the one hand, the application of P2G technology can guide the further integration of the power system and the natural gas system. The power-to-gas balance grid based on water electrolysis is a promising solution, which can effectively reduce the uncertainty of the system dispatching plan. On the other hand, the physical properties of natural gas determine that it can provide a method for the consumption of excess electricity. This paper proposes a peak load shifting calculation model based on an improved genetic algorithm, which smoothes the net load curve of the Gas-electric hybrid energy system through the coordination of P2G and gas-fired generators. The test example used in the algorithm adopts the modified IEEE39-node power network and the coupling system of the Belgian 20-node natural gas system to analyze the static load fluctuations of the system operation under various conditions. It is verified that the power-to-gas conversion and the algorithm researched in this paper can effectively smooth the net load fluctuation and improve the system's new energy absorption capacity.
The capacitance tomography image reconstruction algorithm based on sensitivity field sensitivity matrix
Authors: Xinxin JIA , Xu CHAI , Lei WANG , Hao ZHANG , Xiangchun LI , Liya DUAN , Xiaoling SUN
Published: August 2021

Successful applications of ECT technology depend on the speed and precision of the image reconstruction algorithms. The image reconstruction for electrical capacitance tomography (ECT) is an inherently nonlinear and ill-posed inverse problem. To solve the problems, in this paper 12-electrode ECT system was set up to acquire real measurement capacitances under capacitance tomography that based on sensitivity field sensitivity matrix, which is T-LBP. In this paper four typical flow patterns are simulated, such as laminar flow, core flow, annular flow and bubbly flow, which in a circular section pipe. The simulation data indicate that the quality and the error, which was obtained in this paper, of the reconstructed images were better than the corresponding images obtained by the LBP and the Landweber algorithm. This new algorithm presents a feasible and effective way to research on image reconstruction algorithm for the industrial applications of Electrical Capacitance Tomography System.
Construction of 3D Scene of Transmission Line Corridor Based on GIM and 3D GIS
Authors: Zhao Ping , Yang Wanyun , Feng Yuwei , Li Fangfang , Huang Xueqiang
Published: August 2021

Transmission lines have the characteristics of strip distribution, wide coverage, and close connection with the actual geographical environment. The traditional transmission line modeling method has the defects of insufficient spatial positioning ability and weak information expression ability. Therefore, in this paper, three-dimensional geographic information system (3D GIS) and grid information model (GIM) are coordinated to make the two complementary advantages and construct the three-dimensional scene of transmission line corridor. First, The visible light images and high-precision laser point cloud data of transmission line corridor are collected by helicopter, and extract power lines and towers from the laser point cloud data. Then, the oblique photogrammetric model of large-scale scene is made from visible light images and modified. Finally, according to the point cloud of power line and tower, the improved template matching method is used to realize the rapid modeling of transmission line GIM model, and the transmission line model is obtained. A complete 3D digital twin scene model of transmission line corridor is formed by fusing scene model and transmission line model. The research results show that the 3D scene construction method of transmission line corridor based on 3D GIS and GIM not only improves the efficiency of transmission line modeling, but also has a good visual effect. The abundant line information is helpful for the visual operation and maintenance management of existing transmission lines from macro to micro, which provides data support for the construction of digital power grid.
Design of Three-Dimensional Gesture Recognition and Motion Tracking Human-Computer Intelligent Interaction System based on PAJ7620
Authors: Jian-liang WANG , Ye WEI , Yang LI , Yuan MENG , Ming-yu LI , Jiang-yan XU , Wan-ming JIAO , Lan BAN , Jun-pei LIU , Hong-feng ZHANG , Wei ZHANG , Li-na WANG , Fu-chen LUO , Yu-duo WANG
Published: August 2021

With the increasing degree of informatization and intelligence in modern society, human-computer interaction technology has become one of the commonly used scientific and technological achievements. “Gesture” can be used as inputing image information, and make more intuitive and convenient for perception of user interface. To a certain extent, it can complete the intelligent interaction function between human and computer. The design is a human-computer intelligent interaction system for 3D gesture recognition and motion tracking based on gesture sensor PAJ7620. STM32 chip is used as the main control unit to recognize accurately, analyze and process different gestures collected by the gesture sensor, and control the OLED screen to display the gesture information. It can further drive the carrier to take corresponding actions and realize the intelligent human-computer interaction recognition of gestures. The experimental test results show that the recognition rate is lose to 100% when the distance is within 10cm.
Simulation of multiple unmanned aerial vehicles for compensatory pollination in facility agriculture
Authors: Fan Hao , Yang Minsheng , Wang Ruyi , Wang Xiujuan , Yue Xun
Published: August 2021

In order to enhance the economic benefits of fruit and vegetable cash crop facilities for agriculture, precise stereotactic of compensatory pollination technology in effective pollination period, is the effectively improve the fruit setting rate and the economic benefits of crop. The effects of honeybee pollination on the flowering can provide theoretical support for crop yield and ecological security. However, manual spraying of compensatory pollination technology is high, the working efficiency is low, and the control strategies based on single multiple UAV faces great challenges, which are the effects of flight heights on the droplet deposition and distribution. In this paper, firstly, flow chart of multiple unmanned aerial vehicles in facility agriculture for precise stereotactic of compensatory pollination method is given. Then, the thermogenesis and precise detection of the flower tissues is studied. Last, simulation of 16 UAVs and the effectiveness of the theoretical results is given in Matlab environment. Time varying formation control, formation tracking control of UAVs in facility agriculture, which based on precise stereotactic of compensatory pollination technology, provides a feasible solution scheme for ecological unmanned farm.
Study on Intelligent Meteorological Service of Facility Agriculture Based on Cloud Edge
Authors: Zhangyan Le , Wu Ren , Minghua Shi , Xueying Geng , Qucheng Wei
Published: August 2021

Facility agriculture is an important means of controlling agricultural production environment through engineering technology. However its development cannot be separated from the influence of meteorological elements inside and outside the facilities. This study will improve the level of intelligent meteorological service in facility agriculture and promote rural revitalization. We investigated the current situation of intelligent meteorological service of facility agriculture in Hebei Province and the meteorological observation data in shed. We proposed an application model of cloud edge intelligent weather service based on the digitization, standardization and intelligence of facility agriculture. We independently designed low-cost intelligent nodes. They collect data automatically. The data can be transferred to the cloud for storage and analysis. The cloud displays data in real time. We can stereoscopic monitoring of the distribution points according to the actual situation of the facility greenhouses. These enable accurate data on greenhouse and crop management and planting management. We can model and analyze data at different scales in the cloud. These build the data cube. We can build platforms with different costs through cloud edge synergy. Its advantages are controllable cost and flexible customization. They also allow devices to connect through the cloud. These ultimately achieve intelligent meteorological services for agriculture facilities. We have already carried out preliminary application of the strawberry shed and mochella shed in the Zhaofeng Agricultural Park in Langfang City. Farmers' economic benefits have increased significantly. The economic income per shed increases by $1,600. The results of this study were recognized by the farmers in Hebei province.
Construction and Application of Intelligent Agricultural Greenhouse Irrigation System
Authors: Liu Hong , Li Qing
Published: August 2021

In the environment of scientific and technological progress and the wide application of intelligent agriculture, the project designs and implements an intelligent agricultural greenhouse irrigation system based on MCU, which makes the greenhouse planting of crops more convenient and reasonable The main modules of the irrigation system are soil moisture detection module, liquid crystal display module, timer module, MCU control module and watering module. The system detects the soil humidity through the humidity sensor, displays the humidity on the LCD, and drives the watering module to work through the single chip microcomputer control module. The function of timer is to control the watering time and water consumption, and intelligently complete the automatic work of agricultural greenhouse irrigation system. Through this system design, the application of SCM in various fields can be expanded. It makes the irrigation of agricultural greenhouse intelligent. It provides a solid foundation for the construction of green agriculture.
Design and development of locust monitoring system
Authors: Tan Minghao , Zheng Yubin , Chen Mingtao , Ji Jing , Li Weihua
Published: August 2021

Effective monitoring and early warning of locusts which are one of the main harmful insects in agriculture are the key to protecting farmland ecology. However, due to the large area of farmland, sparsely populated population, inconvenient transportation, network connectivity and other factors, coupled with the locust's own characteristics such as outbreak, migration, and occurrence uncertainty, the task of locust control is very difficult. Traditional survey techniques are far from being able to meet the requirements for real-time monitoring and precise forecasting of the occurrence of locusts. Therefore, this article provides a set of IoT solutions for locust situation monitoring in the context of the Internet of Everything.
Development of the Real-Time Monitoring System for Analysing the Aquatic Epidemics Tendency
Authors: Li Ning , Hu Jing , Cheng JinXiang , Sun YingZe
Published: August 2021

Under the rapid development of globalization, the prevention and treatment of aquatic epidemics has caused widespread concern due to international trade exchanges frequently. Although the epidemic disease information is gathered and published by World Organization for Animal Health (OIE) in regular, some vital characteristics of such disease are not able to obtain directly. Therefore, this technical paper designs a real-time monitoring system jointed Geographic Information System (GIS) and view tables, which aims to help managers or scholars to analyse the aquatic epidemics tendency between the different species and districts. There are mainly three contributions in this paper: (i) the real-time monitoring system of aquatic epidemics researches is first developed from the worldwide perspective; (ii) system provides the superior visual results of statistical analysis on user interface based on the technical processing on data association and light or colour intensities presentations; (iii) Furthermore, the web service is constructed and extended on the separation framework contained web frontend and backend the purpose of which is to reach efficiency of exploitation and failure process.
Design of autonomous navigation system for electric patrol Unmanned Aerial Vehicle Based on Beidou Positioning and satellite based enhancement
Authors: Yang Libo , Yang Jiani , Yao Wencan , Liu Hao
Published: August 2021

In order to reduce the deviation of automatic inspection of transmission tower UAV and improve the efficiency of inspection work, the design of autonomous navigation system of electric power inspection UAV Based on Beidou Positioning and satellite based enhancement is proposed. On the basis of Beidou Positioning and satellite based enhancement, the automatic inspection projector and automatic inspection navigator of transmission tower UAV are designed, and the hardware design of the system is completed. This paper analyzes the endurance of UAV, calculates the coordinates of the best shooting point of UAV, and completes the planning of automatic inspection path of transmission tower UAV according to the horizontal offset coordinates of UAV in the process of transmission tower inspection. Combined with the automatic inspection algorithm of transmission tower UAV, the system software design is completed to realize the automatic inspection of transmission tower UAV. The simulation results show that compared with the traditional inspection system, the deviation of the designed UAV automatic inspection system for transmission tower is significantly reduced.
Design and implementation of code obfuscator based on random opcode
Authors: Si Dan
Published: August 2021

Software obfuscation is a common way of software protection. Source obfuscation and binary obfuscation are unable to achieve universal obfuscation algorithms, while existing compile-time obfuscation algorithms can be effectively restored by symbolic execution. In this paper, an innovative code obfuscation algorithm based on random opcode is proposed. The random number generator is a linear congruence generator written recursively. The algorithm can be used for code obfuscation across languages, platforms and architectures, and has application value for general-purpose software protection. The results of our experiments show this algorithm proposed in this paper can significantly increase the time complexity and space complexity of symbol execution and greatly increase the cost of reverse engineering, which can effectively resist the restore by symbolic execution and has a good confusion effect.
Research on an intelligent electric inspection robot
Authors: Ye Baisong , Song Xiwen
Published: August 2021

Due to the bad environment of electric power inspection, it is easy to cause physical injury to the inspectors. Besides, the heavy workload of inspection is easy to cause the omission of the wireman that leading to major accidents. In order to avoid the mistakes in the process of electric inspection, an intelligent robot for independent inspection instead of manual operation is proposed in this paper. Firstly, the overall configuration of the robot is designed, a four-wheel active driving wheeled mobile mechanism is adopted and the dual parallel camera with three degrees of freedom is carried to inspect the faults existing in the power equipment. Secondly, based on the nonholonomic constraints, the kinematics analysis of the robot is carried out, and the variation laws of the velocity and angular velocity are obtained. In addition, based on the theory of finite element analysis, the modal analysis of the key parts of the robot is carried out to avoid resonance when working to affect the inspection accuracy. Finally, the motion process of the robot in various environments is simulated to verify the correctness of the robot kinematics model and the rationality of the structure design. According to the simulation results, the robot can run stably in typical environments.
Design of intelligent seeding fault monitoring and alarm system for fine seeding machine
Authors: Meng Weiyun , Su Yunlong , Wang Changhu , Qin Lei , Wang Jianxiang , Yan Xinsheng , Pan Yingyue
Published: August 2021

Due to the influence of the operating environment and the design of the corn seeder, the seed will be missed and the quality of seeding will be seriously affected. Based on STM32 single-side machine technology, an operation system for real-time monitoring and remote monitoring of corn seeding operation, which is also a compensation system for the phenomenon of missing seeding during the operation of corn precision seeding machine. The monitoring system is based on the STM32 MCU as the core of the controller combined with human-computer interaction module, reflection type photoelectric sensor, Hall sensor and other principle. The compensation system is composed of self-compensation system and auxiliary compensation system. The monitoring system and compensation system together can effectively solve the phenomenon of maize precision seeding machine in operation, it improves the economy and efficiency of seeding.
Reliability Analysis of Structure Strength based on Spacer Installation Robot
Authors: Liang Liang , Wu Zhengqing , Qian Zhengyang , Liang Wei , Chen Haigen
Published: August 2021

During the construction of high-altitude 10kV power lines, manual installation for spacers has considerably numerous limitations and problems, for example, safety issues, efficiency etc. A new-type spacer installation robot has been introduced to assist the worker to install spacer in air. Prior to put it into usage or production, the reliability of structure strength needs to be tested and verified. This paper verifies the reliability through mathematical calculation and Solidworks/Simulation in which generates stress and displacement plots to determine whether the stresses and elongations in the structure are in a reasonably safe range for both under working conditions and without load.
Intelligent Energy Services Based on Energy Blockchain
Authors: Ling Yunpeng , Xu Nan , Zhou Bo , Yao Suhang , Han Xu , Zhao Zihao , Wang Yongli
Published: August 2021

With the acceleration of Internet information technology, renewable energy technology and electricity reform, the development of integrated energy services has become an important development direction to improve energy efficiency, reduce energy costs, and promote competition and cooperation. Blockchain, as the core technology of industrial innovation and development, has a natural match with the integrated energy service model. The comprehensive energy service mode is analyzed, and the comprehensive energy service model based on block chain master-slave multi-chain structure is constructed. Finally, the operation mode of comprehensive energy service supported by block chain is explored, which provides reference for the application of block chain technology in the comprehensive energy service.
Research on Flexible Interaction Mechanism of Source-Grid-Load-Storage Based on Customer Ubiquitous Electricity Internet of Things Technology
Authors: Rongqing Yi , Xuefei Chang , Zhixin Wang
Published: August 2021

The use of customer-side flexible and controllable load resources to respond to the consumption of clean energy dispatch can significantly reduce the amount of wind abandoning. In this paper, based on Load Segmentation technology, intelligent energy gateway technology, intelligent matching technology, and customer-side flexible load management platform technology, effective practices have been implemented in the aspects of the interaction mechanism, electricity market transaction mechanism and intelligent dispatch response mechanism. It has a good effect on the consumption of clean energy in Jilin Province.
Mine Seismic Exploration Instrument Development and Application Based on £-Δ 24-Bit A/D Converter
Authors: Kun Chen
Published: August 2021

In order to solve the problems of low resolution and poor detection accuracy of current mine seismic exploration instruments, this paper used the data acquisition station of the 24-bit £-ΔA/D converter and the NetBEUI LAN signal transmission protocol to design and develop a synchronization based on the principle of electromagnetic induction. The instrument is a new generation of high-speed, high-resolution mine seismic equipment, and may be applied to geological structure exploration of coal underground channel wave seismic, underground two-dimensional seismic, transient multi-point Rayleigh wave and other seismic work methods. This paper used this instrument to carry out a joint exploration test of channel wave transmission and reflection on a mining face, and through analysis of the collected data, a total of 8 faults and 1 collapse column were delineated, which were confirmed in the later mining face and further verify the accuracy and practicability of the instrument in the safe and efficient mining of coal mines.
Influence of undersea vehicle shafting offset on contact stress and temperature of spherical stern shaft seal
Authors: xuhui Zhou , haoqiang Zhu , jinying Xiong
Published: August 2021

In order to solve the problem that the sealing surface can not adapt itself due to the change of the stern shaft seal of the stern shaft of undersea vehicle. A spherical stern shaft seal structure was proposed in this paper. In order to lay a foundation for the analysis of the sealing performance of the spherical stern shaft seal, a three-dimensional thermal-structural coupling finite element model of the spherical stern shaft seal and the Stern Shaft was established by using ANSYS software. The distribution of contact stress and temperature on the surface of the spherical stern shaft seal was simulated when the Stern Shaft was moving in a series of 0,1,2mm in the vertical direction. The influence of shaft motion on contact stress and temperature on surface of spherical stern shaft seal is analyzed.
Research on the Differential Protection of the SFC Output Transformer for Pumped Storage Hydro Unit
Authors: Long Feng , Wan Luofei , Pan Shuyan , Liu Xiaobao , Wang Zhonglang , Zhao Ruichen
Published: August 2021

Pumped storage power stations play an great role in promoting new energy consumption, ensuring the safety of power grid, building clean, low-carbon, safe and efficient energy system, and has a broad development prospect. SFC is the most important start-up mode of pumped storage unit, and the output transformer is an important equipment of SFC system, which needs to be equipped with reliable and fast differential protection to ensure its safe and reliable operation. The current frequency varies from 0 to 50Hz during SFC start-up, so the conventional transformer differential protection can not adapt. In this paper, the output transformer differential protection technology is studied according to the electrical characteristics and short circuit fault characteristics of SFC start-up process, the high precision frequency algorithm and the RMS integration algorithm with compensation are proposed to realize the precise measurement of frequency and amplitude, and the ultra-low frequency CT saturation identification technology is proposed to realize the whole process protection of the output transformer from start-up to grid-connection.
Triboelectric nanogenerator with deceleration strip for harvesting vibration energy
Authors: Yang Yanfei , Liu Shiming , Li Yikang , Meng Lixia , Li Xiang
Published: August 2021

To achieve the peaking of carbon emission and carbon neutrality, optimizing the energy structure and accelerating the energy transformation has become an inevitable choice to tackle global climate change and promote sustainable development. The search for sustainable clean energy is urgently needed. In this paper, a triboelectric nanogenerator with deceleration strip (DS-TENG) is proposed to harvest the vibration energy in the environment. The DS-TENG comprises a displacement platform, a base plate, and six springs. The experimental data show that the output performance of DS-TENG: the open-circuit voltage 309 V, short-circuit current 16.6 μA, and transferred charge is 96.6 nC. Meanwhile, the DS-TENG can power the LED board with “20” pattern by harvesting energy from human movement. It can be seen the DS-TENG can harvest energy from low-frequency mechanical energy in the environment. Simultaneously the DS-TENG shows its potential application value in the field of energy collection and expands the application space of TENG in the human living environment.
A Sympathetic Inrush Identification Method Using Substation-Area Currents
Authors: Peng Fang , Zhang Yaotian , Li Chong , Zong Xiju
Published: August 2021

Transformers in power system usually take current differential protection as the main protection, but the protection is easy to be affected by inrush currents and then maloperates. Sympathetic inrush is one kind of inrush currents, which is caused by energization of an adjacent transformer. There were many transformer differential protection maloperation cases caused by sympathetic inrush in the field, while the conventional second harmonic restraint method did not work effectively. In this paper, a method based on substation-area currents and curve fitting is proposed to identify sympathetic inrush. The method is presented using the characteristic that sympathetic inrush and initial inrush alternatively appear in reverse polarities. The characteristic exists continuously during sympathetic inrush. In order to verify effectiveness of the proposed method, PSCAD/EMTDC software is used in this paper to build sympathetic inrush model and obtain simulation data. Simulation results prove that the proposed method can effectively identify sympathetic inrush.
Research on Static Potential Distribution Characteristics of Thyristor Valve of UHV Controllable Arrester
Authors: Chen Zhe , Shen Lin , Fang Chonghao , Wang Zhiyuan , Li Pengfei , Deng Zhanfeng , Guo Xianshan
Published: August 2021

The ultra-high voltage(UHV) AC thyristor valve-type controllable arrester can realize the access and exit of the controllable unit through the action characteristics of the thyristor, dynamically change the volt-ampere characteristics of the arrester connected to the system, to reliably and deeply suppress the operating overvoltage. Under continuous operating voltage, stray capacitance will cause the uneven distribution of axial potential at the high-voltage end of the thyristor valve. In severe cases, the thyristor with higher voltage may be triggered by mistake, which endangers the system security. Due to the more changeable potential distribution of thyristor valve under different ambient temperatures and charge rates, higher requirements are put forward for the design and application of the thyristor valve. Therefore, based on the test data, this paper simulates and analyzes the influence of the voltage and temperature changes of the thyristor and resistor on the potential distribution of the thyristor valve under the continuous operating voltage, analyzes and compares the configuration modes of various voltage equalizng capacitors, and obtains the voltage equalizng measures with better optimization effect, which provides a reference for the voltage equalizng optimization of the thyristor valve.
The Method and Practice of Container Electronic Tag Performance Test
Authors: Xu Shibo , Shi Shuquan , Li Jichun , Zhang Shuhui
Published: August 2021

With the rapid development of container transportation, container transportation has become the main mode of transportation that promotes social development and accelerates the process of globalization. The container RFID electronic tag is expected to improve the transportation efficiency of the container. This article describes the testing methods of container electronic tags. At the same time, through the actual application test of container RFID tags, it summarizes and proposes how to optimize the reading efficiency of container electronic tags, so as to achieve the best performance of container RFID tag system.
Estimating the Energy Consumption and Driving Range of Electric Vehicles with Machine Learning
Authors: Wang Yong , Chenlong Wei , Hongwen He
Published: August 2021

The Data-driven methods have been widely used in the SOC, SOH and energy estimation of electric vehicles, and they are recognized as the most promising approaches. However, the popular machine learning methods used for electric vehicles are often “black boxes” which result in the poor interpretation of the model. In this paper, a highly efficient gradient boosting decision tree (LGBM) is proposed to accurately estimate the driving range of electric vehicle. In this model, the feature importance scores are provided to discover the relationship. In addition, the proposed LGBM-T model is capable of generalizing the abstractions by taking into account the key features of time and temperature. Experimental results illustrate that the proposed LGBM-T algorithm is able to reproduce the driving mileage trajectory, with a low mean absolute error (MAE) bounded by 1.681% on real-world vehicles under complex operating conditions. The availability of this algorithm is further corroborated by comparing to the support vector machines (SVM) based estimator.
Numerical Simulation of Temperature Field and Temperature Control of DC Arc Plasma Torch
Authors: Xu Chengjie , Ye Zhihao , Xiao Han , Li Le , Zhang Jiafan
Published: August 2021

In order to study and analyze the internal heat transfer process of DC arc plasma torch, a two-dimensional axisymmetric model of DC arc plasma torch was established based on magnetohydrodynamics and heat transfer theory. The finite element analysis software COMSOL was used to simulate the temperature field under different conditions. The results show that when the terminal current is constant, the DC plasma arc voltage and the average temperature of the torch outlet increase with the increase of nitrogen standard flow rate, and the maximum temperature in the plasma torch decreases with the increase of nitrogen standard flow rate. When the standard flow rate of nitrogen is constant, the arc voltage decreases with the increase of arc current, and the average temperature of plasma torch exit and the maximum temperature in the torch increase with the increase of arc current. The analysis of simulation data provides theoretical guidance for the temperature control of experimental DC plasma torch.
Multi-Objective Optimization Based Joint Dispatch Model of Wind-Solar-Hydro-Thermal Pumped Storage
Authors: Fugang LI , Shijun CHEN , Weibin HUANG , Guangwen MA
Published: August 2021

In this paper, a joint dispatch model of wind-solar-hydro-thermal pumped storage was proposed, taking into account of the basic requirements of minimum system operation cost, minimum load fluctuation and multiple constraints guarantee. Used NSGA-II multi-objective optimization algorithm to solve the problem, so as to verify the feasibility of the model. The model with good adaptability in multi-objective function can optimize the power of pumped-storage units aiming to improving the peak and valley volatility of the net load with pumped storage, and it can optimize the output of thermal power units with the goal of minimizing system operating costs. The pumped-storage effect can be effectively used to relieve the peak load pressure of thermal power units, which can provide a good reference for comprehensively improving the level of renewable energy utilization and increasing comprehensive benefits.
Research on DPCC Control Strategy of PMSM Based on LESO
Authors: Wu Shaonan , Ping Zengliang , Ma Yuhua
Published: August 2021

In permanent magnet synchronous motor control system, the excellent current control effect is very important to the control performance of the system. In order to eliminate the sampling delay in digital control, the deadbeat predictive current control strategy considering sampling delay is proposed. In order to solve the problem that the predictive current control has low robustness to model parameters, especially motor inductance parameters, combined with ctive disturbance rejection control technology, the linear extended state observer is introduced into deadbeat predictive current control to observe and compensate the internal and external disturbances of the system. The introduction of linear extended state observer improves the robustness of system parameters and the ability of anti load disturbance. The final designed system has the advantages of good speed tracking performance, strong anti-interference ability and greatly improved parameter robustness. Finally, the feasibility and correctness of the proposed control strategy are verified by simulation.
Research on Emergency Power Support Method after Distributed Energy Storage System Blocking UHV DC
Authors: Wang Qiang , Meng Zhen , Zhang Zhi
Published: August 2021

In order to explore the emergency support effect of distributed energy storage on reducing the peak power flow of AC transmission lines and improving the operating power of DC transmission lines after UHV DC locking fault, based on the analysis of UHV DC locking fault, the active power is provided according to the distributed energy storage system. A mathematical model is established to reduce the peak power flow of AC transmission lines by distributed energy storage after DC locking. According to the relationship between power gap and frequency variation, a mathematical model of distributed energy storage to improve UHV DC operating power is established. Based on frequency variation and inertial response time, a mathematical model of dynamic response time of energy storage output on system support effect was established. Taking Henan Power Grid of UHV AC/DC hybrid operation as an example, the simulation analysis of distributed energy storage system response in two ways is carried out, which verifies the effectiveness of distributed energy storage system for emergency power support method after UHV DC locking.
Research on pricing model of uninterrupted maintenance for distribution network project of power grid enterprise
Authors: Chen Tianqiong , Ji Kailin
Published: August 2021

Uninterrupted operation of distribution network engineering is an important means to ensure the safe and reliable operation of power supply equipment and improve the level of power supply reliability and quality service. In recent years, with the vigorous promotion of the power grid company, the uninterrupted operation of distribution network has a more rapid and standardized development. At present, the pricing basis of distribution network engineering has not included the content of uninterrupted power operation, which leads to the problems of unable to find the corresponding quota and unclear charging standard in the actual construction charging process. Therefore, it is urgent to study the pricing method of uninterrupted power operation, guide the uninterrupted power operation, standardize the charging, and promote the healthy development of power construction.
Numerical Simulation of Turbine Expander in Natural Gas Pressure Energy Power Generation System
Authors: Zhixing Zhan , Yanqin Mao , Xiaoyue Wang , Chaojie Li , Liang Cai
Published: August 2021

In this paper, the numerical simulation method is used to study the aerodynamic characteristics of the runoff turbine expander, the key equipment in the natural gas pressure energy recovery power generation system. The geometric structure of the turbine expander under the condition of sub-high pressure natural gas expansion was designed and the flow characteristics of the internal flow field during its operation were obtained by numerical simulation. It is found that the expansion process of fluid in the runoff turbine expander mainly occurs in the guide vane channel and the inlet section of the rotor channel. The turbine expander designed in this paper can well meet the working requirements under design conditions, and the flow in the whole channel is good. When the flow channel in the moving impeller changes from radial to axial, the flow field is complex and there is a poor flow. The research results of this paper provide a reference for the design and optimization of runoff turbine expander in natural gas pressure energy power generation system.
Design and Research of Electric Energy Router Based on Double Sliding Mode Control
Authors: Dong Chong , Zuo Qian , Chen WenGuang , Wei Caiyi
Published: August 2021

With the continuous popularization of the concept of the energy internet, the electric energy router, as a key device in the energy internet, has become a research hotspot. The research has designed an electric energy router with a DC bus structure, which is under the double sliding mode control of outer loop voltage and inner loop current. It is verified by PLECS simulation and comparative analysis of Buck circuit PID control and sliding mode control. Design the overall circuit, verify the feasibility of its structure through simulation, and analyze its working status in grid-connected and island mode. The results show that the power router of this architecture can automatically switch the operation mode, realize the free conversion of "source-network-charge-storage", and solve congestion and faults. Through the comparative analysis of PID and sliding mode control, it can be seen that the dual sliding mode control is more advantageous in terms of dynamic characteristics and response speed. The use of dual sliding mode control is simple to implement, which has better error adjustment characteristics and strong robustness, and the addition of distributed power generation can reduce environmental pollution.
Strategy optimization for virtual power plant complied with power to gas operation model
Authors: Zhang Tao , Ma Junhua , Yan Xing , Huang Wenrui , Wang Lei , Xu Shuangqing , Zhang Xuan
Published: August 2021

Virtual power plant (VPP) is an integrated class of integrated power plant composed of energy management system and small and micro distributed energy resources controlled by it. Its distributed energy sources can be distributed generator sets, distributed energy storage equipment or demand response resources distributed among many demand-side users. Its concept emphasizes more on the function and effect presented to the outside world, updating the operation concept and produce social and economic benefits, in line with the needs and direction of China's power development. Given the uncertainty in renewable energy output and demand response, the VPP market of gas networks, Power to Gas (P2G) equipment, flexible loads and other resources are introduced. Furthermore, VPP's optimal scheduling strategy includes considering power and gas scheduling for both power and gas flows, and studies the optimization model considering the dual energy market to maximize the profits of VPP. Through example studies, the economics and scheduling strategies of the proposed VPP are analyzed. Simulation results show that the VPP proposed in this paper can effectively reduce the proportion of renewable energy emissions reduction by selling power or P2G equipment. Moreover, it is conducive to maintaining the pressure stability and safe operation of the natural gas power grid. VPP can reduce the cost of unbalanced punishment and reduce the impact of uncertainty.
Multi-objective optimization configuration of wind-solar-storage microgrid based on NSGA-III
Authors: Yu Jinghao , Sun Changhai , Kong Ruixi , Zhao Zhe
Published: August 2021

Reasonable allocation of the capacity of micro power supply such as wind turbine, photovoltaic and battery is the premise to ensure the economic, reliable and environmental protection operation of microgrid. Aiming at the capacity allocation problem of grid connected microgrid, this paper establishes a multi-objective optimal allocation mathematical model of grid connected microgrid considering the economy, reliability and environmental protection of microgrid, and uses the genetic algorithm NSGA-III based on the reference point selection mechanism to obtain the multi-objective Pareto solution set of micro source capacity allocation. The simulation results show that NSGA-III can not only optimize the three objective functions better than NSGA-II, but also improve the distribution uniformity of Pareto solution set and the diversity of population. The simulation results show that NSGA-III algorithm is more suitable for multi-objective optimal configuration of microgrid.
Photovoltaic fault diagnosis model based on dynamic switching
Authors: Chen Nanzhou , Hu Shan , Zhu Wenhao , Wang Fei
Published: August 2021

PV module fault diagnosis is mostly based on the prediction of photovoltaic module's power generation in the short term, and the fault of the module can be judged by comparing the difference between the actual power generation and the predicted power generation. However, the photoelectric conversion efficiency of photovoltaic modules varies significantly with seasons and weather, single prediction model is lack of stability, the season in a significant and a change in the weather forecast results will appear large deviation, this will lead to frequent false alarms of fault diagnosis, make power plant maintenance and repair costs unnecessarily. According to the characteristics that the photoelectric conversion efficiency of photovoltaic modules is greatly affected by weather and season, a fault diagnosis method for photovoltaic power generation based on dynamic model switching is proposed. when meet preset conditions, using the different quarters of historical data, combined with recent data to update the model, improved the fitness of model for the current weather and season. Compared with a single fixed model, the results show that the proposed method has better adaptability to different seasons and different weather.
Analysis of the Influence of Nuclear Power Extraction Steam Heating Reformation on Steam Turbine OPC
Authors: Shao Jiaye , Hao Yuhua , Wu Zhigang
Published: August 2021

This article analyzes the influence of the OPC signal transmission, OPC test and OPC action function of the steam turbine before and after the heating renovation of a nuclear power plant, and compares the simulation test of the relevant simulator. The analysis result shows that after the nuclear power plant's heating reformation, the impact on the original steam turbine OPC is not obvious, and it also provides support for the stable operation of the transformed unit, and also provides a reference for subsequent related projects.