bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of Half-bridge Bidirectional DC-DC Converter Control Loop
Authors: Cheng Huan , Guo Yingna , Ma Zhao , Bai Sisi 
Published: May 2021

Abstract
In recent years, the direct current (DC) microgrid system has received extensive attention from industrial and academic circles worldwide. As an essential part of the DC microgrid, the bidirectional DC-DC converter can realize the bidirectional flow of energy according to the needs of the DC microgrid. In this paper, the half-bridge bidirectional DC-DC converter is taken as the research object, and the double closed-loop feedback control loop of the converter in the charging and discharging mode is designed based on the intermittent and fluctuating characteristics of distributed generation. Besides, a simulation model is built using MATLAB to analyze the operation of the converter in different modes and the control effect of the double closed-loop feedback control loop. The results verify the effectiveness and feasibility of the proposed control method.
Exploration and application of small well spacing development management mode in oilfield
Authors: Zhuo Wang 
Published: May 2021

Abstract
The oil field enters the stage of ultra-high water cut development, especially after the third infilling, the well spacing is small. The water injection advances quickly, the water cut rises quickly, the control of natural decline becomes more and more difficult. According to the traditional oil field development management method, the oil field steady production difficulty will increase continuously. Therefore, we must constantly explore new methods of oilfield development to improve the quality and benefit of oilfield development.
Study on the law of Ultrasonic Wave Plugging
Authors: Yuzhen Liu 
Published: May 2021

Abstract
In the Chang Yuan area of Daqing oilfield, the field test of ultrasonic oil layer removal is carried out in the oil layer with different physical properties, different dynamic conditions and different water quality conditions. We evaluated the overall effect of ultrasonic remove near wellbore plugging, the system of technology parameters and reservoir static parameters, the dynamic parameters and quality of production of ultrasonic lift effect of near wellbore blockage, and ultrasonic, chemical plugging effect comparison. The test results show that the field parameters, static parameters of the reservoir and the dynamic parameters of production all affect the effect of ultrasonic plugging. The total processing time is longer, the better; layer selection priority Portuguese group two and senior group; under the same conditions, priority maximum permeability and small coefficient of variation, a small number of small, high strength injection layers; reservoir pollution, ultrasonic plugging treatment sooner the better. The initial injection efficiency of the two ways of chemical agent and ultrasonic wave is close, and the effective period of the plugging well is longer than that of acidizing well. Under the condition that the production cost of oil field is more and more precise, ultrasonic plugging and unmoving string, short construction time and long effective period can be used as a conventional plug removal method in oilfield application.
Research on calibration test technology of Multi-component force sensor
Authors: Liu SIbo , Qin Haifeng , Liu Yonglu , Chen Wei 
Published: May 2021

Abstract
Multi-component force sensor is a common force measurement instrument that can perceive all six force values and torque values in space. It is mainly used in aerospace, equipment manufacturing and other fields. At present, the calibration of multi-component force sensor is mainly carried out in professional measurement laboratory with special measuring equipment. In the field of measurement and control, the stress condition of multi-component force sensor is very complex, and the sensitivity obtained by calibration test often has certain deviation from the sensitivity of multi-component force sensor under actual load condition. This paper analyzes and tests the common problems of the multi-component force sensor in the actual measurement, control and calibration test. The test proves that the combined loading and loading order and loading position of the multi-component force sensor will affect its sensitivity output. It is necessary to pay attention to the related influence in the use of multi-component force sensor and design the calibration scheme according to the specific loading situation.
Application of Frequency Domain Dielectric Response Method in Intelligent Location of Oil Paper Insulation Bushing Damp Fault
Authors: Wu Jing , Zhang Shaoming 
Published: May 2021

Abstract
Oil paper insulating bushing is widely used in 500 kV and above power transformers. In order to quantitatively study the influence of water content on the dielectric spectrum of oil paper insulated bushing, HN model was used to fit and analyze the dielectric spectrum parameters of oil paper insulated bushing with different water content. The experimental results show that HN model can be used to evaluate the wettability of oil paper insulation, but the evaluation range of wettability of oil paper bushing with complex insulation structure is not clear. The results show that the relaxation time constant decreases with the increase of water content, and has a linear relationship with the change of water content; the difference between high frequency dielectric constant and static dielectric constant increases with the increase of water content.
Procedures for Identifying Mutual Inductance of Three-Coil Structure for Wireless Power Transfer in Electric Vehicles
Authors: Liu Peizhou , Gao Tiande , Mao Zhaoyong , Liang Bo 
Published: May 2021

Abstract
Mutual inductance identification of the wireless power transfer (WPT) system is of great significance for improving the system performance. In this paper, a novel mutual inductance identification method for WPT in electric vehicles with three-coil structure is proposed based on the information measured from the primary and relay coils. The method deduces the influence of misalignment on mutual inductance of three-coil WPT system in electric vehicle application scenarios from a new perspective. The results show that the mutual inductance between primary and secondary coils, and the mutual inductance between relay and secondary coils can be estimated at one time by way of index according to the relationship between their ratio and themselves. Experimental results show the correctness of the proposed mutual inductance identification method.
Measurement method of adjacent harmonics or interharmonics based on Gaussian radial basis function frequency domain approximation
Authors: Guo Cheng , Duan Ruimin , Zeng Ye 
Published: May 2021

Abstract
Interpolated FFT method based on window function is a common method to measure harmonics or interharmonics in power systems. When the frequency resolution is insufficient or the main lobe of the window function is wide, the spectrum of adjacent harmonics or interharmonics may have aliasing of the main lobe, and it is difficult to accurately measure the parameters of harmonics or interharmonics. This paper proposes a modeling method for adjacent harmonics or adjacent interharmonics. The Fourier transform (FT) of the Gaussian function is still a Gaussian function. According to this feature, after adding a Gaussian window in the time domain and calculating the FFT spectrum, the real and imaginary parts of the aliased spectrum are decomposed into a series of linear superpositions of Gaussian radial basis functions (RBF). The center of the RBF is the frequency of the harmonic or interharmonic, and the amplitude and phase can also be calculated by the superposition coefficient of the RBF. The simulation verifies the effectiveness of the method.
Research on Power Demand Response of A Certain Area Power Grid for New Energy Consumption
Authors: Zhang Yi , Wu Yifeng , Zhang Feng , Cai Jianqiang , Li Yang , Tang Lv 
Published: May 2021

Abstract
With the rapid growth of new energy installation scale, new energy consumption is facing more and more pressure and challenge. Based on the characteristics of a certain provincial power grid, this paper starts from the point of view of promoting clean energy consumption, guiding electric heating load and other adjustable loads to optimize electricity consumption, relieving peak-shaving pressure of power grid, and strengthening the emergency regulation ability of the certain power grid, the power demand response of provincial power grid is designed and realized. This mode and methods have universal application value for provincial power grid with high proportion of new energy installation.
Operation control strategy of load aggregator based on new energy consumption in power grid
Authors: Jiang Mingjun , Wang Xiang , Dai Fengjiao , Xu Lanlan , Wen Xin , Shen Rendong 
Published: May 2021

Abstract
Managing the scattered small and medium-sized load by the existing ternary market model of regenerative electric heating is difficult. In this paper, the load aggregator is introduced on the basis of the traditional ternary market, transforming the existing ternary market model into the quaternary market transaction mode of new energy, power grid, load aggregator and regenerative electric heating users. The coupling relationship of four parties’ interests is studied for the win-win solution limited by the goal of obtaining the maximum income and assuming the minimum risk. A case of Northeast China is carried out and the results show that the maximum profit point is 0.5 yuan/kWh, 0.3 yuan/kWh and 0.1 yuan/kWh respectively.
Digital Twin of Beam Pumping Unit Control and Analysis
Authors: Ren Shuang Shuang , Shen Fei , Zhang Xiang Yang , Feng Chao Min , Luo Hong Wu 
Published: May 2021

Abstract
The software model of beam pumping unit was built through the physical simulation pumping unit lifting system in the Internet of Things laboratory, and the lifting model was updated after mutual verification to form the digital twin system of oil and gas production lifting. Based on the digital twin of beam pumping unit and the real-time data of oil and gas production, the whole process of oil and gas lifting process production is formed, and a flexible closed-loop control method based on the digital twin is obtained. The method is based on the detailed and in-depth analysis of the whole movement, which selecting the load as the monitoring physical quantity, and improving the system efficiency. The method is to change the maximum and minimum load, reduce the input power and improve the system efficiency under the condition of maintaining a certain output. By comparing and analyzing the indicator diagram of oil well production before and after the flexible control, the flexible control method based on digital twin reduces the loss of mechanical operation and saves the consumption of electric energy, so that the efficiency of the pumping unit’s lifting system reaches the maximum. At the same time, the control and analysis method based on digital twinning is a self-diagnosis, adjustment and control method of intelligent ecology, which is the inevitable trend of the development of intelligent oilfield.
Design and Test of Downhole Weight on Bit-Based Autodriller System for Horizontal Well
Authors: Wu Zebing , Zhang Wenchao , Zhou Kefei , Zhao Haichao , Huang Hai , Wang Jie 
Published: May 2021

Abstract
During horizontal well drilling, the pressure difference between the downhole weight on bit (DWOB) and the surface weight on bit (SWOB) will affect the service life of the drilling tool and the efficient production of oil and gas fields. An automatic drilling system device based on DWOB is designed. Choose the S7-200 smart PLC with good expansibility, combine the drilling rig automation principle, and use the Smart-700IE-V3 touch screen to design the human-computer interaction interface. Realize the real-time monitoring and prediction of DWOB. A large amount of test data shows that the new system not only has the advantages of the conventional automatic drilling system, but also can reduce or even eliminate the pressure difference between the surface and the bottom of the hole, achieve accurate control of the DWOB, improve bit performance, and reduce drilling costs.
Intelligent recognition of defects in vermicular graphite cast iron engine cylinder head by ultrasonic testing
Authors: Liu Qingyi , Jiang Ailong , Fang Duo , Zhang Chengqiang , Liu Zenghua , Liu Zehua , Guo Yanhong 
Published: May 2021

Abstract
To detect and intelligently identify the defects of the vermicular cast iron cylinder head, defective casting samples were made corresponding to each type of the actual defects. We setup the ultrasonic testing system to examine the defective samples. The detected defect signals were processed to obtain the characteristic spectrograms of the defects, which were further sorted and classified into a sample database. An algorithm based on a convolutional neural network was proposed to identify the defects intelligently. A convolutional neural network model was established. The network structure and parameters were optimized. It shows that a neural network with 3×3 convolution kernel dimension, 3 convolution layers, 20 convolution kernels in each layer and a learning rate of 0.0005 can effectively identify the spectrograms of the defects. The results show that the identification accuracy of the proposed algorithm is 97.14%. The model meets the practical requirements of cylinder head defect detection. The detection efficiency has improved significantly.
Fuzzy Control Strategy of Relief System for Extra-High Pressure Test Equipment
Authors: Xiao-hui Liang , Yu-de Fan 
Published: May 2021

Abstract
To realize accurate super-high hydraulic pressure curve control of relief system for isostatic pressure test equipment, a method of designing fuzzy control strategy, including theoretical analysis, modeling, designing fuzzy controller, optimizing fuzzy rules and simulation, was introduced. Precise mathematic model based on theoretical inferring and experimental computing was developed and used for studying control strategy and optimizing control rules. High-accurate controller based on fuzzy control theory was studied and fuzzy controller rules were optimized. A simulation platform composed of input variable, controller, mathematic model and output variable was obtained and successfully used for studying the control of relief process. Computer simulation and physical test experiments indict that the control precision of relief system reaches ±0.5Mpa during the pressure domain above 30MPa, the fuzzy controller strategy meets the high-accurate pressure control requirements of super-high pressure test equipment.
Research and Application of Knowledge Decision Method for Optimal and Fast Drilling in Emergency Rescue Wells
Authors: Yingzhuo Xu , Mingzhen Li , Yang Zhang , ZiXiang Yin 
Published: May 2021

Abstract
The efficiency of coal mine emergency rescue work is limited by the professionalism of decision-making, the efficiency of rescue team formation and the rate of resource mobilization. Knowledge sharing and inheritance have important reference meanings for improving the efficiency and success of rescue work. In order to improve the efficiency of rescue work, this article builds A knowledge base that meets the needs and research on key content[1]. This article first analyzes the knowledge engineering, knowledge representation and knowledge storage of emergency rescue well drilling; secondly, based on the analysis of the emergency rescue well work flow, it classifies the knowledge of fast drilling, and studies the knowledge expression based on ontology[2]. Construct the ontology model of knowledge and establish the knowledge base; then, in view of the shortcomings in the current knowledge retrieval, apply the full-text search to the retrieval of the fast drill-in knowledge, construct the retrieval model and design the index structure of the knowledge base, on this basis The ranking of knowledge retrieval is optimized. Finally, combine the retrieved knowledge and follow the emergency rescue process to form a set of decision-making plans. Through the application of the case study in this article, it is shown that the standardized management of the knowledge of excellent and fast drilling in emergency rescue wells is realized, the speed and quality of the acquisition of knowledge of excellent and fast drilling are improved, and the efficiency and professionalism of decision-making are improved.
Application of Downhole Camera Technology in Fault Diagnosis of Coalbed Methane Wells
Authors: Yin-hua Liu , Xue-jie Xing , Yu-bin Wang , Wan-yong Xu , Kai Liu , Yuan Lv 
Published: May 2021

Abstract
In the production process of coalbed methane well, due to casing damage, falling objects, sticking and other reasons, the continuous production is affected. In order to accurately identify the complex conditions of the gas well, the underground real-time camera technology can be used to diagnose the complex conditions of the underground, and provide a reliable operational basis for the next step of the overhaul construction measures. Through field application, the downhole camera technology can provide an accurate real-time picture of the gas wellbore, clearly capture the complex situation in the casing from the wellhead to the bottom of the well. It is of great guiding significance to analysis the causes of downhole faults and develop accurate repair measures.
An adaptive magnetization structure and method for low field NMR two-phase flow measurement
Authors: Li-pin LI , Rui-qiang Han , Yan-qun Huang , Huan Chen 
Published: May 2021

Abstract
In low field NMR multiphase flow measurement, the magnetization time and magnetization length are affected by the two-phase flow velocity and water fraction, so it is difficult to realize the complete magnetization of multiphase flow with fixed length magnet. In this paper, an adaptive magnetization structure for two-phase flow is proposed. The pre-magnetization model of the adaptive structure is established based on the magnetization theory of nuclear magnetic resonance. And parameters of the adaptive magnetization structure are determined by analyzing the influence of two-phase flow parameters such as velocity and water fraction on magnetic susceptibility. Finally, the simulation analysis shows that the adaptive magnetization structure can achieve complete magnetization effect for two-phase flow in the range of water fraction 0-36% and flow rate 0-4.66m/s, which provides the necessary conditions for the accurate measurement of NMR two-phase flow and provides a new idea for the design of NMR two-phase flow measurement sensor.
Seismic Signal Filtering based on Pseudo Wigner-Ville Distribution and Catte Model
Authors: Yanping Liu , Zheng Ma , Huiqin Jia , Jianshen Gao 
Published: May 2021

Abstract
In practice, there are various noises included in the collected seismic data. As a common background noise, random noise may interfere even annihilate valid signals. In view of this, it needs to adopt effective methods to eliminate random noise as much as possible. This paper proposes a filtering method that is based on pseudo Wigner-Ville distribution (PWVD) and Catte model. PWVD is a windowed form of Wigner-Ville distribution (WVD) which can make the nonlinear signal to be locally linearized in addition to weakening the influence of cross item. And the Catte model is a kind of anisotropic diffusion algorithm which can eliminate the noise while protecting the edge of image. The implementation of the proposed method is to do PWVD for the frequency modulation form of noise-containing signal and then to filter the PWVD via Catte model, at last to adopt peak search to obtain the estimation of the valid signal.
Research on a high-precision and high-resolution seismic wave signal acquisition system
Authors: Dan Wu , Hongtao Wu , Guowang Gao , Fei Wang 
Published: May 2021

Abstract
In oil and gas exploration, high-resolution seismic acquisition is an important research content of seismic exploration methods. In order to improve the accuracy and high resolution of the seismic wave acquisition system, a seismic wave signal acquisition system based on the 32-bit high-resolution analog-to-digital converter ADS1282 is designed in cooperation with a high-anti-interference and high-resolution piezoelectric geophone, Improve the resolution of seismic wave signal acquisition from the two aspects of seismic wave pickup and analog-to-digital conversion. The system chooses the high-performance, ultra-low power consumption Microcontroller MSP430F149 as the control core of the acquisition system, which effectively reduces system power consumption. System debugging results show that the collected data of ADS1282 is stable to 24 bits, and the consistency is good.
Image Mosaic in Visual Detection of Wellbore
Authors: Xifeng YI , Yuguo Liu , Feng Zhang , Hengchao Gao , Yugang Tian , Jianfei Wei , Zhengguo Yan , Yinchuan WU 
Published: May 2021

Abstract
Based on the research on the visual detection system, this paper analyzes the characteristics of wellbore video (image), proposes the key techniques of image processing, and designs the methods of image mosaic. The experiment results show that when the image correction, the perspective transform, the image registration, and image fusion are implemented, a panoramic image of wellbore can be obtained. This study provides a new perspective for the visual detection and the technology reserves for further quantitative evaluation of visual detection.
Performance analysis of a wavelet packet transform applied to concrete ultrasonic detection signals
Authors: Hu Tianyu , Zhao Jinhui , Yan Shubin , Zhang Wei 
Published: May 2021

Abstract
In the ultrasonic detection technology of concrete health conditions, it is difficult to identify damage features due to the complex wave synthesis of detection signals. We propose a method of applying wavelet packet transform (WPT) to decompose and reconstruct the ultrasonic detection signal from a C30 class concrete, thereby reducing noise and redundant information. We can obtain the main frequency node coefficients by wavelet packet decomposition, and reconstruct the denoised signal by the node coefficients. For analyzing the performance of this method, the extracted indices of signal-to-noise ratio, root mean square error, Pearson correlation coefficient, and smoothness are utilized and evaluated respectively. Ten simulated signals and ten actual detection signals are employed for evaluating the method. Simultaneously, the comparison with the calculation results of the empirical mode decomposition (EMD) method is created. It is shown from the experimental results that WPT has better denoising performance on the signals. Finally, an experiment of the processed signal quality assessment is constructed. The stochastic configuration network (SCN) is employed as the evaluation model for exploring the influence of the proposed denoising method on identification accuracy. The result shows that the proposed method of reconstructing the main frequency node coefficients by WPT retains useful information more effectively and improves the identification accuracy of the recognition model.