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14th IEEE International Symposium on Power Electronics for distributed Generation Systems, PEdG 2023

作者： Hu, Sideng Tahir, Mustafa Niu, Jianfeng Fujishima, Naoto Lei, Yun He, Xiangning Zhejiang University College of Electrical Engineering Hangzhou China Fuji Electric Co. Ltd. Semiconductors Business Group Matsumoto Japan Fuji Electric Co. Ltd. Technology Strategy & Planning Office Corporate R&d Headquarters Japan

ISBN: (纸本)9798350328233

Multiple power modules are interfaced in parallel via laminated busbar in high-capacity active neutral-point clamped (ANPC) converters. consequently, the complex mutual coupling among parallel branches profoundly affects their equivalent stray inductance. This study analyzes mutual coupling between parallel branches on the same plane of the busbar and how it affects the equivalent stray inductance, which has not been thoroughly reported. A mutual inductance experimental extraction method is proposed and a mathematical model of stray inductance is established. Then, using the proposed method, stray inductance and mutual inductance of two parallel branches for an ANPC busbar are calculated. Experimental tests verify the accuracy of the proposed method. © 2023 IEEE.

关键词： Busbars

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Vegetation Shading Fault diagnosis in Photovoltaic Power Stations Based on SVM 2

Vegetation Shading Fault Diagnosis in Photovoltaic Power Sta...

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2nd IEEE International Power Electronics and Application Symposium, PEAS 2023

作者： Wang, Zeao Ma, Mingyao Ma, Wenting Xu, Qian Zhang, rui Hefei University of Technology National and Local Joint Engineering Laboratory for Renewable Energy Access to Grid Technology Hefei China National and Local Joint Engineering Laboratory for Renewable Energy Access to Grid Technology Hefei China Sungrow Smart Maintenance Technology Co. Ltd. R&d Center Hefei China

ISBN: (纸本)9798350313765

Aiming at vegetation shading faults in photovoltaic (PV) power stations, a fault diagnosis model based on support vector machine (SVM) is proposed. According to the seasonal variation characteristics of PV string currents, the characteristics of vegetation shadings are extracted, and the characteristic matrix is established. Through the field operation data, the model was established for training and verification. The diagnostic results of SVM with different kernel functions are compared through experiments, and the diagnostic results of different machine learning are compared. The results show that the SVM algorithm can effectively identify shading faults of PV power stations, and the fault diagnosis accuracy is high. © 2023 IEEE.

关键词： fault diagnosis PV power stations SVM vegetation shading

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research on construction and operation parameters of an underground oil storage in depleted salt caverns in the east of China 82

Research on construction and operation parameters of an unde...

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SPE Europec featured at 82nd EAGE conference and Exhibition, EUrO 2021

作者： Jin, Fu Xi, Wang Mingming, ding Guobin, Yang Shunyuan, Zhang Bingshan, Liu Chen, Chen CNPC Engineering Technology R&D Company Ltd. China China National Oil and Gas Exploration and Development Company Ltd. China

ISBN: (纸本)9781613997918

The crude oil price has been keeping at a low level in recent years, which made China's government put more efforts in the development of underground oil storages in depleted salt caverns. Under the initiative of "the Belt and road", a more concrete concept which is "the Silk road Economic Belt and the 21st-Century Maritime Silk road"successfully connects Jiangsu Province in the east of China. consisting of 20 depleted caverns, Huai'an project that is still under planning is one of the most successful examples that turn depleted salt caverns into underground crude oil storages in China. Each cavern takes up 24×104m3, while the project totally takes up 480×104m3. TdMA algorithm was adopted to solve the heat exchange model of oil, brine and surrounding rocks, revealing the relationship between temperature and cavern pressure. Salt rock safety factor, salt cavern shrinkage ratio, axial stress and ground subsidence were taken into consideration to establish a 3- dimension salt rock creep model for 19 depleted salt caverns, so that the caverns' shapes were optimized. Hydrodynamics models were used to determine the oil's flow rate into and out of a 1000m deep cavern whose thermal field was simulated by software to reveal the temperature limit of oil and brine. due to geothermal gradient and continuous heat transmission, the average temperature of oil and brine goes up from 35°C to 44.3°C within 7 years, while the inner pressure goes up from 12.96MPa to 21.93MPa in a depleted salt cavern. Salt creep ratio decreases as oil is stored in underground caverns for a longer period. Salt is hardly penetrated by oil, while the temperature change has a strong influence on caverns' internal pressure. The thermal expansion factor and compressibility coefficient of crude oil and brine are both crucial to the temperature's effect on internal pressure. Caverns that have larger segments in their uppermiddle or middle parts are more stable and resistant to salt creep than those that have l

关键词： Crude oil

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3d Point Cloud Classification Based on convolutional Neural Network 4th

3D Point Cloud Classification Based on Convolutional Neural ...

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4th EAI International conference on 6G for Future Wireless Networks, 6GN 2021

作者： Lu, Jianrui Kang, Wenjing Ma, ruofei Qin, Zhiliang Department of Communication Engineering Harbin Institute of Technology Weihai Weihai China Technology R&D Center Weihai Beiyang Electric Group Co. Ltd Weihai China

ISBN: (纸本)9783031042447

With the development of science and technology, the requirements for 3d point cloud classification are increasing. Methods that can directly process point cloud has the advantages of small calculation amount and high real-time performance. Hence, we proposed a novel convolutional neural network(CNN) method to directly extract features from point cloud for 3d object classification. We firstly train a pre-training model with ModelNet40 dataset. Then, we freeze the first five layers of our CNN model and adjust the learning rate to fine tune our CNN model. Finally, we evaluate our methods by ModelNet40 and the classification accuracy of our model can achieve 87.8% which is better than other traditional approaches. We also design some experiments to research the effect of T-Net proposed by Charles r. Qi et al. on 3d object classification. In the end, we find that T-Net has little effect on classification task and it is not necessary to apply in our CNN. © 2022, ICST Institute for computer Sciences, Social Informatics and Telecommunications engineering.

关键词： convolutional neural networks

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research on reactive Voltage Optimization in distribution Networks Using Graph Neural Network-Based reinforcement Learning

Research on Reactive Voltage Optimization in Distribution Ne...

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Smart Grid and Artificial Intelligence (SGAI), International conference on

作者： Hui Liu Lucheng Hong Ying Lu Xingrui Zhang School of eletrical engineering Southeast University Nanjing China Technology R&D Center ASWEI Technology Co. Ltd. Suzhou China

ISBN: (数字)9798331518806

ISBN: (纸本)9798331518813

With the increasing integration of distributed renewable energy, distribution networks are facing increasingly severe issues such as voltage violations and increased network losses. Although there has been considerable research on reactive power voltage control using reinforcement learning, few studies have successfully maintained good performance when distribution network topology changes or data is missing. In this paper, a reactive voltage control strategy for distribution networks is proposed, which integrates Graph Neural Networks (GNNs) and the Twin delayed deep deterministic Policy Gradient (Td3) algorithm. This method effectively addresses the shortcomings mentioned above. First, the reactive voltage control problem in the distribution network is modeled as a Markov decision Process (MdP). The GNN is used to extract topological features of the distribution network, thereby enhancing the agent's perception of the system state and robustness, enabling the optimization of reactive power output for photovoltaic inverters and Static Var compensators (SVCs). Finally, simulations are conducted on the improved IEEE 33-node system, and the results demonstrate that the proposed method performs excellently in reactive voltage control for distribution networks.

关键词： Training reactive power Adaptation models Markov decision processes distribution networks Feature extraction Graph neural networks Topology Smart grids Voltage control

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Improving the Performance of a Polyamine Shale Inhibitor by Introducing a Hydrophobic Group in Oil and Gas development

SSRN

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SSrN 2023年

作者： Huang, Xianbin dai, Zhiwen Zhang, Chao Lv, Kaihe Meng, Xu Wang, ren Lalji, Shaine Muhammadali Khan, Muhammad Arqam Ministry of Education Qingdao266580 China Qingdao266580 China CNPC Engineering Technology R&D Co. Ltd. Beijing102206 China NED University of Engineering & Technology Karachi75270 Pakistan

Wellbore instability in complex shale formations is a major technical problem that restricts drilling safety and efficiency. In this paper, a hydrophobic cationic polyamine shale inhibitor (HCPA) was prepared by introducing a hydrophobic group into the molecular structure of an amine-based shale inhibitor having a branched structure. The shale inhibition performance of HCPA and the amine-based shale inhibitor without the hydrophobic group (CPA) was investigated. The hydration inhibition mechanism of HCPA was studied by experiments of zeta potential, particle size, contact angle, thermogravimetric analysis (TGA), X-ray diffraction (Xrd), Fourier-transform infrared spectroscopy (FTIr), et al. The evaluation results show that HCPA had a better performance than CPA in terms of inhibition of hydration swelling, hydration dispersion and mud making, which indicates that the hydrophobic group is beneficial to improve the inhibition ability of the amine-based shale inhibitor. Mechanism study show that there is no hydrogen bond between HCPA and clay. The adsorption on the clay surface is mainly driven by electrostatic interaction, which reduces the repulsion of the electric double layer and thus inhibits the osmotic hydration of clay. HCPA could greatly increase the water contact angle of the rock and the mud cake. The contact angle of the rock and mud cake could reach 133° and 69.5°, respectively, when the concentration of HCPA is 0.5%. TGA and Xrd tests proved the bentonite modified by HCPA had a lower weight loss of at 200 °C than bentonite modified by CPA, and interlayer spacing of HCPA-modified bentonite was reduced compared with that of unmodified bentonite, indicating that the ability of bentonite to adsorb water molecules is reduced after the introduction of hydrophobic groups. This can effectively inhibit the surface hydration of clays. In addition, HCPA can reduce the imbibition capacity of rocks by reducing the surface tension of water. This paper can provide theor

关键词： Bentonite

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A scaffold with zinc-whitlockite nanoparticles accelerates bone reconstruction by promoting bone differentiation and angiogenesis

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Nano research 2023年第1期16卷 757-770页

作者： Mingming Wang Jiaxin Yao Shihong Shen Chunning Heng Yanyi Zhang Tao Yang Xiaoyan Zheng Shaanxi Key Laboratory of Degradable Biomedical Materials Shaanxi R&D Center of Biomaterials and Fermentation EngineeringSchool of Chemical EngineeringNorthwest UniversityXi’an 710069China Biotech.&Biomed.Research Institute Northwest UniversityXi’an 710069China Xi’an Giant Biogene Technology Co. Ltd.Xi’an 710069China Shaanxi Key Laboratory for Theoretical Physics Frontiers Institute of Modern PhysicsNorthwest UniversityXi’an 710127China

The therapy of bone defects based on advanced biological scaffolds offers the most promising therapeutic strategy for bone *** is still challenging to develop scaffolds with the mechanical,osteogenic,angiogenic,and antibacterial properties required for bone defect ***,a novel organic/inorganic composite scaffold(zinc-whitlockite(ZnWH)/G/H)was synthesized using gellan gum(GG),human-like collagen(HLC),and ZnWH *** scaffold had excellent mechanical properties,adjustable swelling ratio,and interconnected pore *** addition to its excellent biocompatibility,it could promote osteogenic differentiation by releasing ZnWH nanoparticles to stimulate human bone marrow mesenchymal stem cells(hBMSCs)to upregulate the levels of alkaline phosphatase(ALP),osteocalcin(OCN),and osteopontin(OPN).In addition,this study showed that ZnWH nanoparticles could also promote angiogenesis by upregulating the paracrine secretion of vascular endothelial growth factor(VEGF)in *** the same time,the scaffold could inhibit the proliferation of *** 12 weeks of treatment in the rabbit femoral defect model,the ZnWH/G/H scaffold significantly accelerated the process of bone ***,these results demonstrate that the prepared novel nanocomposite scaffold,ZnWH/G/H,offers a promising candidate for bone regeneration.

关键词： bone repair nanocomposite scaffold zinc-whitlockite osteogenesis angiogenesis

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Bus Sub-station Lines Optimization Based on Analysis of Main Passenger Flow in the Same direction

Bus Sub-station Lines Optimization Based on Analysis of Main...

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International conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Wei, Qingbo Xuan, Qipeng Su, Kui Sha, Zhiren Su, Yuejiang Guangzhou Public Transport Data Management Center Co. Ltd. Guangzhou510620 China Guangzhou Municipal Transportation Bureau Guangzhou510620 China Guangzhou Fundway Smart Transportations R&D Co. Ltd. Guangzhou510000 China School of Civil Engineering and Transportation South China University of Technology Guangzhou510641 China

ISBN: (纸本)9789819639601

In traditional design of bus sub-station lines, most are based on experience model, which is easy to distribute the same direction lines at different sub-stations, resulting in a decline in passenger travel experience. To solve this problem, this study proposes an automatic calculation method for the optimal bus sub-station lines. Based on the actual travel Od of bus passengers, stopping lines and their departure frequencies, distribution of downstream bus station, and the stopping capacity of each sub-station, a Genetic Algorithm (GA) model is constructed to solve the optimal scheme. In the GA algorithm, the fitness function is "passengers with the same Od board at the same sub-station as much as possible, and travels of the same direction board at the same sub-station as much as possible", and in the process of selection, crossover and mutation, limitation of each sub-station’s stopping capacity is also fully considered. Finally, some sub-stations in Guangzhou is taken as the test object, with "the total number of passengers boarding at the same sub-station" and other indicators are taken as the test index. results show that after optimization, the stopping sub-station of bus lines in the same direction are more concentrated, and the number of passengers who fully enjoy taking the line at the same station increases by 71%. Overall, this study can provide engineering application solutions for automatic design of bus sub-station lines. © Beijing Paike Culture commu. co., ltd. 2025.

关键词： Genetic algorithms

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Field Test of Lithium Extraction in Oilfield Associated Water: A Case Study of YQ Treatment Station

Field Test of Lithium Extraction in Oilfield Associated Wate...

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2024 Abu dhabi International Petroleum Exhibition and conference, AdIPEC 2024

作者： Miao, Xinyue Wen, Zhang ren, Yongcang Wang, Min Wang, Kelin Zhao, Zhiyong Liu, Zhiming Han, Guoqiang Ma, rui Chen, Xin Zhang, Lei deng, Qianxing Tarim Oilfield Company CNPC Xinjiang Province Korla City China Engineering Research Center for Ultra-deep Complex Reservoir Exploration and Development Xinjiang Uygur Autonomous Region Xinjiang Province Korla City China R&D Center for Ultra Deep Complex Reservior Exploration and Development CNPC Xinjiang Province Korla City China Southwest Petroleum University Sichuan Province Chengdu City China Xinjiang Key Laboratory of Ultra-deep Oil and Gas Xinjiang Province Korla City China Shanghai Huiliyuan Technology Co. Ltd. Shanghai City China BGP CNPC Hebei Province China

ISBN: (纸本)9781959025498

The oilfield associated water is complex in composition and poses significant hazards, necessitating treatment to prevent environmental pollution. Taking the Yingqian Treatment Station as an example, it processes approximately 2,400m3 of water daily. Sampling and testing revealed that the total hardness of the water exceeds 20,000mg/L, with a Mg2+ concentration of about 1,200mg/L. Most importantly, the Li+ concentration reached 150mg/L, meeting the requirements for economic development (≥50mg/L). consequently, related research and experiments were promptly initiated. Owing to the associated water's high total hardness and low lithium content, which significantly differ from saturated brine, traditional lithium extraction techniques cannot be directly applied. In response, research has identified that manganese-based adsorbents offer the advantage of high adsorption capacity, but require concentrated acid for desorption. conversely, bipolar membrane electrodialysis has the merit of producing lithium products with high purity;however, the byproduct concentrated acid is a hazardous chemical that necessitates proper disposal. consequently, a combined technological approach has been proposed to leverage the strengths of both methods. The lithium extraction experiment from oil-gas field associated water at the YQ Treatment Station in China was conducted from May to June 2023, successfully producing 2.05kg of monohydrate lithium hydroxide from 116m3 of associated water. However, the experiment encountered numerous issues. For instance, the LiCl solution after a single desorption with HCl failed to meet the feed concentration requirements for subsequent processes. After extensive argumentation, the solution was adjusted by using a mixture of LiCl and HCl from the first desorption to replace HCl as the desorbent, and adjusting the desorption process from one stage to two, thereby increasing the LiCl concentration. The daily production of associated water in blocks such as Yi

关键词： Gas industry

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research and application of drilling rig optimization model

Research and application of drilling rig optimization model

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2024 8th International conference on Electrical, Mechanical and computer engineering (ICEMCE)

作者： Yue Xiao Tuo Zhou Guojun Liu Xuanren Chen Xiangji Kong Yu Zhang Longlong Liu Shunong diao CNPC Engineering Technology R&D Co. LTD PetroChina International Exploration and Development Co. LTD Overseas Drilling and Completion Technology Center Beijing China PetroChina International Exploration and Development Co. LTD Beijing China Changchun University of Technology Changchun China China University of Petroleum (Beijing) Beijing China

ISBN: (数字)9798331506230

ISBN: (纸本)9798331506247

The optimal selection of drilling rigs is crucial for the rational arrangement of drilling rigs in multi operation teams, the improvement of moving operation management level, and the enhancement of drilling operation quality and efficiency. At present, the optimal selection of drilling rigs only considers whether the drilling meets the needs of the drilling project and the moving distance, and cannot comprehensively and scientifically select drilling rigs, which is not conducive to the rational configuration evaluation of oilfield drilling rig operation. This article comprehensively considers key indicators such as drilling efficiency, time efficiency, moving cycle, moving cost, and moving distance, innovatively forms a pentagonal drilling rig optimization coordinate system, establishes drilling rig optimization rate, comprehensive standard deviation, drilling rig optimization comprehensive standard deviation and other indicators, and forms a drilling rig optimization model for drilling. Taking Block B as an example, the priority of Block B with three drilling rigs to be optimized calculated using the model is ${\mathrm {r}}1\gt {\mathrm {r}}2\gt {\mathrm {r}}3$.The optimal selection rate of drilling r1 is the highest, the comprehensive standard deviation is smaller, and the comprehensive index of the best and more stable drilling performance is the highest, which is 0.0058. Therefore, r1 should be selected for drilling. The drilling rig optimization model proposed in this paper provides a process reference for drilling rig optimization, quantifies various indicators, and provides a theoretical basis for new well drilling rig optimization, project company drilling rig operation plan formulation, and improving project company drilling rig management level.

关键词： drilling costs Uncertainty Optimization models computational modeling Stability criteria companies complexity theory Standards Optimization

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