bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on insulation performance of EPR cable terminal containing metal particles
Authors: Jisheng Huang , Enxin Xiang , Lini Li 
Published: February 2020

Abstract
The 35kV EPR cable terminal is widely used in the distribution network. During the production process, metal particles are easily introduced due to environmental and technological reasons, resulting in frequent breakdown of the terminal breakdown accident. In order to study the influence of metal particles on the insulation performance of EPR cable terminals, a model of metal particles defect in cable terminals on the extension line of the main insulation and the control tube is built. The electric field distribution of cable terminals under power frequency voltage is calculated by COMSOL simulation software. At the same time, a sample of cable terminals containing metal particles is made, and local discharge is used. The partial discharge information of the cable terminal sample is tested by the electric test platform. The results show that the introduction of metal particles will increase the electric field distortion inside the cable terminal, strengthen the discharge activity of the cable terminal, and increase the discharge amount significantly, which seriously affects the insulation performance of the EPDM cable terminal.
Energy management for isolated microgrid to mitigate “demand & abandon” phenomenon with two types of subsidy policies
Authors: Liming Li , Weidong Chen , Xueqi Shi 
Published: February 2020

Abstract
This paper presents a game model about the microgrids energy management problem and its implementation in the centralized energy management system for isolated microgrids. The model mainly provides power management strategies based on the problem that power is imbalance, and analyses the impact of two types of subsidy policies on “Demand & Abandon” in the operation of microgrid. By analysing the experiment results, we conclude that: 1) energy storage device improves the flexibility of power usage strategy; 2) the implement of infrastructure subsidy policies can solve “Demand & Abandon” in a better way while the electricity subsidy policies are invalid.
Stability analysis of DC microgrid considering the action characteristics of relay protection
Authors: Huang Lu , Qun YU 
Published: February 2020

Abstract
The stability of microgrid is the key issue of microgrid operation control. This paper focuses on the transient stability after the correct operation of relay protection. In this paper, 400V DC microgrid with photovoltaic and energy storage system is taken as the research object. Research on the fault characteristics of voltage and current after the system is subjected to short-circuit, it is proposed to introduce current differential protection. With bus voltage as the only indicator, whether the transient stability is improved after the protection system operates correctly. The DC microgrid is modeled and simulated based on MATLAB/Simulink to confirm the validity of the proposed statement. The simulation results show that the fault can be correctly located, accurately isolated and timely removed by the protection system after the short-circuit fault occurs, bus voltage is restored to maintain stable operation of the system.
Optimal design of energy sstorage capacity of distributed photovoltaic microgrid based on random error model
Authors: Jin Longfei , Ju Zhenhe , Duan Desheng , Kong Fanju 
Published: February 2020

Abstract
The allocation of capacity of distributed photovoltaic energy storage System has always been an urgent problem to be solved, and reasonable capacity allocation plays an important role in stabilizing the power fluctuation of PCC node and smoothing the load output. In order to reasonably configure energy storage, this paper establishes an energy storage model based on the analysis of random error, which combines load prediction error and the randomness of photovoltaic output prediction error to meet the characteristics of normal distribution, and estimates the random error not considered by the original model, so that the results calculated by the model are more accurate. Combining with the example of the Liaoning branch of China Tower, and the capacity configuration of the photovoltaic energy storage system is verified by combining its load power and photovoltaic power curve.
Research on protection configuration of AC/DC hybrid distribution network in industrial park
Authors: Wenjing XIE , Feng Kangheng , Jianzong HE , Zheng Fenglei , Zhong Rongfu 
Published: February 2020

Abstract
Under the rapid development of power electronics technology, AC/DC hybrid power supply can be used to comprehensively solve the demand for source and supply.The article takes the first comprehensive demonstration project of the dual-stage AC-DC hybrid system based on multi-function power electronic transformer cluster in China as the research object.A distributed renewable energy system simulation platform with AC/DC hybrid is established in the hardware RTDS to simulate and analyze the fault characteristics under different conditions.Based on the fault characteristics and the principle of protection division, in order to ensure that the ranges between the protection zones overlap each other and cover the entire AC-DC distribution network,This paper studies the specific protection zones and configurations for the industrial park system, and has developed a comprehensive protection configuration plan.
Research on key technologies of highly reliable flexible distribution facing tidal load
Authors: Qiang LIU , Shen Peifeng , Di WU , Zhuofei YU , Jian LUO , Zhao Chen 
Published: February 2020

Abstract
Under the background of steady development of DC transmission and distribution technology, a series of pilot projects and demonstrations have been carried out gradually in the Engineering application of DC distribution network. In this paper, the typical mode of low voltage DC distribution network- flexible distribution system, is taken as the main research object. The interface between low voltage DC distribution and AC distribution, the distributed energy resource and electric vehicle, and the characteristics of electrical load is considered synthetically. The DC voltage level, power supply radius and capacity, the mode of grounding and connection, and topology structure are analyzed and studied. The typical DC distribution structure is analyzed by simulation. And the DC network load mutual supply experiment system suitable for different scenarios is constructed.
Advanced design and optimization of wind turbines based on turbine theories
Authors: Zhang Zh 
Published: February 2020

Abstract
A review of wind turbine technology showed that many flaws in both the flow models and computations are involved in the traditional fundamentals. While traditional methods for design and computation are all based on the airfoil theory, a new method based on turbine theories has been developed and is shown to be ideally applicable. Against the traditional method, the new method also considers non-uniform pressure distribution in flows downstream of the rotor plane and is thus highly accurate. The blade efficiency or tip swirl number has been introduced. It enables computation of the power coefficient to be very reasonable. Its optimum can be directly applied to the geometrical design of turbine blades. Between the tip speed ratio X, blade efficiency e, and power coefficient cp, a closed solution of both the optimum design and the operation of wind turbines exists. It is demonstrated that the maximum achievable power coefficient can be 10% larger than that predicted by all previous theories.
Research on case management technology of power market simulation
Authors: Gaoqin Wang , Ailin Chen , Jianhu Lü , Hong Zhang , Yaxian Zheng 
Published: February 2020

Abstract
The construction of electric power spot market in China is gradually advancing. Since the operation of electric power spot market is affected by various factors such as grid structure, supply and demand situation and external environment, and is closely related to grid operation, it is difficult to predict through theoretical analysis and estimate the operational effect of the market, so before the formal operation of the power spot market, it is necessary to verify and analyze the operational process and operational effects of the market. In order to facilitate the recording of market operation process and result data under various simulation scenarios and to carry out data comparison and to analyze the causes and influencing factors of market operation effects, this paper proposes case management and case data comparison of the electricity market operation simulation. The case management is used to manage the process and result data of the market operation simulation, and support the data comparison and analysis of different simulation scenarios, it provides technical support to the verification analysis of the operation effect of the power market and the effective factors.
Analysis of DC inter-electrode fault overvoltage in AC/DC hybrid power system
Authors: Zhong Rongfu , Siwei WAN , Yunfeng XIA , Dongliang WEI , Wenzhi HE 
Published: February 2020

Abstract
AC/DC hybrid power system has become an important distribution system for high-proportion distributed renewable energy consumption and multi-energy supply. Among the DC-side fault overvoltage, the inter-electrode fault overvoltage is the most harmful to the system. In order to analyze the principle of overvoltage generation, this paper establishes a mathematical model for AC/DC hybrid power system, and researches the mechanism of inter-electrode fault overvoltage generation on the DC side of the system, and builds a Matlab/Simulink simulation model so that gets the simulation analysis results of lOkV DC and ±375V DC side in the system. The research shows that the system high-frequency mathematical model relation which obtained according to the mathematical mode is belongs to the coupled nonlinear time-varying system. The DC-side overvoltage development can be divided into three stages: after happening of the fault until the converter station is locked, after the converter station is locked until the fault is removed, after removal of the fault until the converter station is unlocked. Through modeling and simulation, it is verified that the development process of overvoltage is consistent with the theoretical analysis. According to the research conclusion, the method of ‘arrester + parallel resistance + grounding device’ is proposed to protect the DC side overvoltage of the system.
Optimization of the slotted liners parameters during dual tubing steam injection process
Authors: Li Peng , Zhang Yanyu , Hu Hang , Liu Yunlong , Liu Yang , Chen Huijuan 
Published: February 2020

Abstract
To study the distribution of steam parameters along the wellbore and the influence of slotted liners parameters on the effect of reservoir uniform preheating during the dual tubing steam injection process. Based on the structural characteristics of screen pipe completion and the simultaneous steam injection technology of long and short tubing, a coupled numerical model of fluid flow and heat transfer in reservoir and wellbore was established, and the model was solved by full implicit finite difference method and iterative technique. The results show that when the density, width and length of the slotted liners increase from 350 to 550/m, 0.20 to 0.40 mm and 35 to 75 mm, respectively, the difference of steam quality at the two ends of steam convergence position in the annuli increases by 0.41%, 2.26% and 1.71%, and the reservoir heating uniformity decreases by 1.49%, 2.68% and 2.08%, respectively. Optimizing the slotted liners parameters and reducing the steam quality difference at the convergence position of annuli can improve the uniform heating degree of reservoir along the horizontal wellbore.
Equivalence analysis of multiple monitoring methods for partial discharge
Authors: Fan Lu , Shao Zhenhua , Shen Hanxin , Li Zezhong , Sun Lijie 
Published: February 2020

Abstract
In order to study the relationship between the amplitude (mV) and the discharge (pC) of a typical fault of a tip discharge in a partial discharge. Therefore, three different groups of tip electrode models (tip-tip, tip-plate, tip-ball) were simulated. The relationship between magnitude and discharge volume and voltage was obtained by using amplitude detection method (Ultra High Frequency Method, Acoustic Emission Method and Transient Earth Voltage method) and Pulse Current Method respectively. Kendall correlation analysis found that the amplitude and the voltage of the AE Method in the three amplitude detection methods are closest to the variation trend of the discharge quantity and the voltage of the Pulse Current Method. Exploring the equivalence between the amplitude and the discharge of the most accurate detection means, the mathematical model with the best fit is the Sum of Sin Functions.
Research on key technologies of high voltage and large capacity static synchronous series compensator control system
Authors: Yuan Peie , Wang Xiang , Chen Guofu , Jia Xiaoguang , Dai Fengjiao , Yu Zhiyong , Wang Yingpei 
Published: February 2020

Abstract
With the rapid development of economy, the structure of power grid is becoming more and more complex, which has brought about uneven distribution of power flow, limited transmission capacity and the decline of power quality. The application of new static synchronous series compensator can quickly and effectively regulate power flow, suppress sub-synchronous oscillation and enhance system stability on the basis of guaranteeing transmission capacity. In practical engineering application, the design of control system and the realization of control algorithm are very important. In this paper, the control system of 220 kV 30MW self-excited SSSC device is developed based on the control and protection platform of serial RapidIO technology. Firstly, the main topology structure of SSSC is introduced, and the two-stage DC voltage stabilization and upper steady-state operation control strategy of SSSC using fast response control method which simultaneously regulates modulation ratio and trigger angle are expounded. Secondly, the dual redundancy control system architecture is designed, and the control system implementation scheme is designed. Finally, the RTDS power in the loop experimental system is designed, and the control algorithm is verified by RTDS experiments. The experimental results show that the control strategy and control system implementation scheme adopted in this paper can realize smooth start-up and exit of SSSC device and flexible regulation of power flow. The developed control system can satisfy the long-term reliable and stable operation of the system, especially the design of redundancy mechanism, and increase the reliability of the device operation. Follow-up static synchronous series compensator project and even FACTS project provide reference.
Estimating the boundary of the asymptotic stability region of Lotka–Volterra system by using the trajectory reversing method
Authors: Lai Yi-Horng , Fang Liang 
Published: February 2020

Abstract
This paper proposes a topological approach for plotting the boundary of the region of asymptotic stability (RAS) of Lotka–Volterra predator-prey system. First, stability analysis was used to determine the specific saddle point that has eigenvalues with one positive and two negative real parts in a linearized Jacobian matrix. A set of initial states located around the saddle point on the specific eigenplane spanned by the two stable eigenvectors was then selected. Finally, the trajectory reversing method was used and the trajectories that had initial states on the eigenplane delineated the boundary of the asymptotic stability region. The trajectories of the initial states that started from the opposite sides of the RAS exhibited different dynamic behaviour. The numerical simulation are presented to demonstrate the effectiveness of the proposed approach.
Introduction and prospect of integrated energy service platform in industrial parks
Authors: Feng Gu , Kai Xie , Hao Jin , Hengxun Su 
Published: February 2020

Abstract
As a modern industrial division of labor and production area that adapts to market competition and industrial upgrading, the industrial park is a generation model for the country to actively plan and promote development. The integrated energy system of industrial parks is of great significance for improving energy efficiency, promoting large-scale development of renewable energy, improving the utilization of social infrastructure and energy supply, and achieving energy conservation and emission reduction targets. The combination of industrial parks and integrated energy service platform technologies can realize the coordinated operation and resource sharing of various energy systems, meet the individual needs of campus users, and provide diversified services for system maintainers, park managers, enterprises, and households. Based on the summary of the characteristics of the campus-type energy Internet, the paper studies the key technologies of its integrated energy service platform. The key technologies of information collection, source-charge prediction, multi-energy coordination scheduling and advanced application services of the company’s latest integrated energy service platform are introduced, and suggestions for the development of integrated energy service platform in the park are put forward.
Prospect analysis of high temperature air combustion technology for low calorific value coalbed methane in Liupanshui area of Guizhou province
Authors: Zhou Yu , Ji Xiaowei , Tang Jie 
Published: February 2020

Abstract
China’s coalbed methane resource is abundant, which ranks third in the world. The total amount of coalbed methane resources in Guizhou Province accounts for about 10% of China, which ranks second in the country. However, the utilization rate of coalbed methane in Guizhou Province is not only low, but also relatively single, especially the low calorific value coalbed methane extracted from underground mines which has a methane concentration of only 10-30%. And the main method to deal with low calorific value coalbed methane is discharging directly, which caused a huge waste of energy. High temperature air combustion technology (HTAC), which expands the utilization range of low calorific value fuels, has attracted wide attention due to its characteristics of extreme recovery of waste heat and ultra-low NOx emission. In this paper, the characteristics of high temperature air combustion of low calorific value coalbed methane are analyzed by theoretical and numerical calculation based on combustion theory and CFD method.
Hour-ahead photovoltaic power forecast using a hybrid GRA-LSTM model based on multivariate meteorological factors and historical power datasets
Authors: Chen Biaowei , Lin Peijie , Lin Yaohai , Lai Yunfeng , Cheng Shuying , Chen Zhicong , Wu Lijun 
Published: February 2020

Abstract
Owing to the clean, inexhaustible and pollution-free, solar energy has become a powerful means to solve energy and environmental problems. However, photovoltaic (PV) power generation varies randomly and intermittently with respect to the weather, which bring the challenge to the dispatching of PV electrical power. Thus, power forecasting for PV power generation has become one of the key basic technologies to overcome this challenge. The paper presents a grey relational analysis (GRA) and long short-term memory recurrent neural network (LSTM RNN) (GRA-LSTM) model-based power short-term forecasting of PV power plants approach. The GRA algorithm is adopted to select the similar hours from history dataset, and then the LSTM NN maps the nonlinear relationship between the multivariate meteorological factors and power data. The proposed model is verified by using the dataset of the PV systems from the Desert Knowledge Australia Solar Center (DKASC). The prediction results of the method are contrasted with those obtained by LSTM, grey relational analysis-back propagation neural network (GRA-BPNN), grey relational analysis-radial basis function neural network (GRA-RBFNN) and grey relational analysis-Elman neural network (GRA-Elman), respectively. Results show an acceptable and robust performance of the proposed model.
Online photovoltaic fault detection method based on data stream clustering
Authors: Cai Yuqiao , Lin Peijie , Lin Yaohai , Zheng Qiao , Cheng Shuying , Chen Zhicong , Wu Lijun 
Published: February 2020

Abstract
As the core component of solar power station, PV array is particularly important for safe and stable operation of the entire system. The existence of PV array faults for a long time can lead to potential danger of the entire PV system. Since the PV data is greatly affected by the environment, the continuous data stream generated during the operation of PV arrays can form clusters of arbitrary shape. When a PV fault occurs, new data streams can form a cluster that is different from the one under normal operation. Accordingly, this paper presents a model for online fault detection of PV arrays faults using data stream clustering approach. The real-time data stream of the PV arrays is transmitted to the diagnostic system through RabbitMQ server for online detection and data storage. The online density-based spatial clustering of applications with noise (DBSCAN) algorithm is used for clustering the data. Then, the faults are detected by judging whether new clusters are formed. The experiment result shows the effectiveness of the proposed method in grid-connected PV system.
Study on carbon emission reduction mechanism of thermal power plants in medium and long term trade
Authors: Zhang Xuefei , Xiong Yi , Xiong Chuanyu , Tang Xuejun , Li Zhiwei 
Published: February 2020

Abstract
Electricity market is gradually tending to be more energy-saving and environmental-friendly. In the context of medium and long-term electricity trading mechanisms, it is important to implement energy-saving and emission reduction with more reasonable and effective mechanism to solve the shortcomings in the overall environment and achieve energy conservation. The author finds that the core idea of energy conservation and emission reduction mechanism abroad to internalize the external cost. After in-depth study, the author summarizes the problems in realizing energy conservation and emission reduction in the medium and long-term electricity trading mechanism in the current market. The core design ideas and main development models of the mechanism are analyzed. Finally, the author analyses the design of market mechanism under the mode of trading volume restriction and power transfer in power plants. In the whole process, the author makes an auxiliary analysis with actual cases for peer exchange.