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A Quantitative Characterization of the Crack driving Force of the Popcorn-type Failure in Mold-Underfilled Package under Hygro-thermo-vapor Loads by Finite Element Based Fracture Mechanics 26

A Quantitative Characterization of the Crack Driving Force o...

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26th Electronics Packaging technology Conference, EPTC 2024

作者： Lyu, Guang-Chao Luo, Ming-Sheng Zhang, Xin-Ping School of Materials Science and Engineering Guangdong Provincial Engineering Technology R&D Center of Electronic Packaging Materials and Reliability South China University of Technology Guangzhou510640 China

ISBN: (纸本)9798331522001

This study investigates the combined effects of hygroscopic expansion, thermal expansion and vapor pressure on the reliability of molded underfill flip-chip (MUF FC) packages using finite element analysis. The moisture concentration distributions during MSL 1 preconditioning and the reflow process were first determined. Moisture diffusion under varying temperature conditions during reflow was simulated using the internal source approach. Fracture behavior at the MUF/die interface, specifically at the interface crack tip and the die corner, was analyzed for different crack lengths based on fracture mechanics. It has been found that vapor pressure loading becomes the dominant driving force for interfacial crack propagation and deflection at the die corner when the crack extends to a certain extent. Under vapor pressure loading, the Mode I driving force is predominant at the interface crack tip, while under moisture and thermal loads, the crack driving force is influenced by both Mode I and Mode II components. In addition, the direction of crack deflection at the die corner, which is predicted using the maximum tangential stress (MTS) criterion under the vapor pressure loading condition, is significantly different from that under moisture and thermal loads. In practical engineering, the cracking angle can serve as a key factor in analyzing the primary types of loads that lead to structural damage and device failure. The conclusions derived from the study enhance the understanding of popcorn failure mechanisms in electronic packages and provide valuable insights for research related to integrated circuit (IC) reliability. © 2024 IEEE.

关键词： Crack tips

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Vibration condition analysis based on surface-underground engineering measurement parameters 7

Vibration condition analysis based on surface-underground en...

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7th International Conference on downhole Measurement and Control, ICdMC 2024

作者： Fan, Jinchao Fang, Chao Xu, Zhaohui Lin, Zili CNPC Engineering Technology R&D Company Limited Beijing102206 China National Engineering Research Center of Oil & Gas Drilling and Completion Technology Beijing102206 China

Accurate identification of abnormal vibration conditions is an important guarantee for drilling safety. In the process of deep oil and gas and unconventional oil and gas production, only the surface parameters can not effectively identify the abnormal vibration conditions in the drilling process. It is an important method to accurately identify abnormal vibration conditions to obtain the engineering parameters near the bit by using downhole parameter measurement tools and analyze the data combined with the surface logging data. To solve the above problems, this paper firstly studies the storage downhole parameter measurement tool, which can obtain the parameters of weight on bit, speed, torque, temperature, pressure and acceleration near the bit position. Finally, field tests are carried out, and the experimental results show that the tool can effectively obtain engineering parameters near the bit position, and can effectively identify abnormal downhole vibration conditions based on surface-downhole parameters, which can provide strong support for drilling operations. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Infill drilling

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design and Experiment of Turbine Generator Applied to Gas drilling 13th

Design and Experiment of Turbine Generator Applied to Gas Dr...

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13th International Field Exploration and development Conference, IFEdC 2023

作者： Wang, Lei Guo, Xian-Wei Shi, Hong-Jiang Cao, Chong ding, Hua-Hua CNPC Engineering Technology R&D Company Limited Beijing102206 China National Engineering Research Center of Oil and Gas Drilling and Completion Technology Beijing102206 China

ISBN: (纸本)9789819702558

With the maturity of electromagnetic wave transmission measurement while drilling technology, em wave transmission tools have been applied to the measurement and control of gas drilling well trajectory. However, due to the dry shaft wall and poor conductivity of gas drilling, especially the electromagnetic wave signal attenuates obviously in the formation, the transmission distance is affected. Enhance the emission power of electromagnetic waves could decrease the impact of signal attenuation, At present, measurement while drilling system is powered by battery in gas drilling, but the output of battery power is limited. The downhole generator technology can effectively improve the emission power of the signal source, However, due to the low gas density and compressibility, the conventional turbine components cannot drive the rotor shaft of the downhole generator as normal. This paper use the classical formula to determine the performance parameters of the gas drilling downhole generator body, Based on the study of the velocity vector triangle of the turbine blade in the two-dimensional flow field, analyzed the relationship between turbine output speed and torque in gas drilling conditions, then proposed to increase the torsional characteristics of turbine output by using planetary gear mechanism, through the above research, the air-drive turbine suitable for gas drilling is developed. CFd software is used to simulate the full three-dimensional flow field of the turbine, and the simulation results meet the design expectations. The test verifies that the steady-state output of the gas-driven turbine generator can reach 500 W, which meets the high-power emission requirements of electromagnetic wave transmission in gas drilling. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Electromagnetic waves

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A novel reprocessable chloroprene rubber based on dynamic disulfide metathesis

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International Journal of Smart and Nano Materials 2024年第1期15卷 42-61页

作者： Jianliang Jiang Junxue Zhai Yanqing Chen dongqi Zhao Yakai Feng School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and Chemical Engineering(Tianjin)Tianjin UniversityTianjinChina R&D Department of China(Yangzhou) Material Handling Tech-Engineering LtdYangzhouChina Key Laboratory of Rubber Plastics of Ministry of Education/Shandong Province (QUsT)School of Polymer Science&EngineeringQingdao University of Science&TechnologyQingdaoChina R&D Department of Tianjin Joaboa Technology Co.Ltd TianjinP.R.China Frontiers Science Center for Synthetic Biology Tianjin UniversityTianjinChina Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjinChina

For sustainable application of chloroprene rubber(Cr),a new technology is developed by the vulcanization of Cr using 2,2'-dithiodipyridine(dPd)as a cross-linking agent with the repro-cessing performance owing to disulfde *** dPd was incorporated into Cr vulcanization,the Menschutkin reac-tion between allyl chloride group and pyridine group occurred with a maximum exothermic peak at 184°*** number of effective cross-linking bond at o.5 phr dPd vulcanizate was higher than that at high dPd *** vulcanizate showed high tensile strength(11.12 MPa)and elongation at break(1253±120%)owing to the exchangeable disulfide bond in the *** the catalysis of triphenylphosphine,the metathesis of disulfide compound was improved obviously,which endowed Cr/dPd vulcanizates with good recyclability *** cross-linkage maintains its stability at low temperature,thus ensuring the mechanical stability of Cr/dPd vulcanizate under the ambient *** and reprocessing of Cr/dPd vulcanizate can be conducted with common industrial rubber processing *** reprocessable chloroprene rubber could have potential appli-cation in Cr industry,also serve to significantly improve envir-onmental sustainability.

关键词： Chloroprene rubber reprocessable Menschutkin reaction disulfide

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Evaluation of the combined influence of geological layer property and in-situ stresses on fracture height growth for layered formations

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Petroleum Science 2024年第5期21卷 3222-3236页

作者： Peng Tan Zhao-Wei Chen Liu-Ke Huang Qing Zhao Sha-rui Shao CNPC Engineering Technology R&D Company Limited Beijing102206China National Engineering Research Center for Oil&Gas Drilling and Completion Technology Beijing102206China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu610500SichuanChina Shale Gas Research Institute Southwest Oil&Gas Field CompanyChengdu610500SichuanChina

Fracture geometry is important when stimulating low-permeability reservoirs for natural gas or oil production. The geological layer(GL) properties and contrasts in in-situ stress are the two most important parameters for determination of the vertical fracture growth extent and containment in layered rocks. However, the method for assessing the cumulative impact on growth in height remains ambiguous. In this research, a 3d model based on the cohesive zone method is used to simulate the evolution of hydraulic fracture(HF) height in layered reservoirs. The model incorporates fluid flow and elastic deformation, considering the friction between the contacting fracture surfaces and the interaction between fracture components. First, an analytical solution that was readily available was used to validate the model. Afterwards, a quantitative analysis was performed on the combined impacts of the layer interface strength, coefficient of interlayer stress difference, and coefficient of vertical stress *** results indicate that the observed fracture height geometries can be categorized into three distinct regions within the parametric space: blunted fracture, crossed fracture, and T-shaped ***, the results explained the formation mechanism of the low fracture height in the deep shale reservoir of the Sichuan Basin, China, as well as the distinction between fracture network patterns in mid-depth and deep shale reservoirs.

关键词： deep shale Hydraulic fracturing HF propagation Fracture interaction Cohesive zone method

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Ultrathin polyamide nanofiltration membrane prepared by triazine-based porous organic polymer as interlayer for dye removal

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Chinese Journal of Chemical engineering 2023年第5期57卷 193-201页

作者： Yongbo Liu Zhihao Si Cong ren Hanzhu Wu Peng Zhan Yuqing Peng Peiyong Qin National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China College of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Membrane Science and Technology College of ChemicalEngineeringBeijing University of Chemical TechnologyBeijing 100029China

Separation membrane with high flux is generally encouraged in industrial application,because of the tremendous needs for decreasing membrane areas,usage costs and space *** most effective and direct method for obtaining the high flux is to decrease membrane ***(PA)nanofiltration membrane is conventionally prepared by the direct interfacial polymerization(IP)on substrate surface,and results in a thick PA *** this work,we proposed a strategy that constructing triazine-based porous organic polymer(TrZ-POP)as the interlayer to prepare the ultrathin PA nanofiltration ***-POP is firstly deposited on the polyethersulfone substrate,and then the formed TrZ-POP provides more adhesion sites towards PA based on its high specific surface *** chemical bonding between terminal amine group of TrZ-POP and the amide group of PA further improves the binding force,and strengthens the stability of PA *** importantly,the high porosity of TrZPOP layer causes the higher polymerization of initial PA owning to the stored sufficient amino monomer;and H-bonding interaction between amine groups of TrZ-POP and piperazine(PIP)can astrict the release of ***,IP process is controlled,and the thinnest thickness of prepared PA layer is only<15 *** expected,PA/TrZ-POP membrane shows a more excellent water flux of 1414 L·m^(-2)·h^(-1)·MPa^(-1)than that of the state-of-the-art nanofiltration membranes,and without sacrificing dye *** build of TrZPOP interlayer develops a new method for obtaining a high-flux nanofiltration membrane.

关键词： Polyamide Nanofiltration Interfacial polymerization Triazine-based porous organic polymer

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Instability and Stabilization Filter of df/dt-Type Virtual Inertia Control Comparing to Synchronous Machines

IEEE Open Journal of Power Electronics

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IEEE Open Journal of Power Electronics 2025年 6卷 849-857页

作者： Ueda, Takumi Sano, Kenichiro Terazono, daisuke Nada, Kaho Institute of Science Tokyo Department of Electrical and Electronic Engineering Meguro Tokyo1528550 Japan Mitsubishi Electric Advanced Technology R&D Center Hyogo Amagasaki6618661 Japan

With the increase of inverter-based resources, the reduction in grid inertia has become an issue. To overcome this problem, various virtual inertia controls have been proposed. df/dt control is a candidate for practical application since it can be integrated into conventional current controlled inverters. However, df/dt control can make the system unstable under certain conditions. A common solution is to use a low-pass filter (LPF), but there is no clear answer to why df/dt control becomes unstable and the LPF can improve stability. As a result, there are no general design criteria of the LPF for various plants. This paper focuses on the stability of a current-controlled inverter with df/dt-type virtual inertia control. The authors analyze the dynamic characteristics of a synchronous generator and demonstrate the existence of a second-order delay between the frequency of the point of common coupling (PCC) voltage and the speed of the rotor. The result demonstrates an equivalence between this delay and LPF for stabilization in df/dt control. Then, this second-order delay is implemented in df/dt control as an LPF. The influence of this LPF for stability is analyzed by EMT simulations and Bode plot of the entire system. These results illustrate that the LPF is indispensable for df/dt control, and parameters corresponding to synchronous generators can be used as a design criterion of the LPF. © 2020 IEEE.

关键词： Stabilization

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Low Switching Frequency Motor drive Using All Switching Patterns Search based direct Torque Control 50

Low Switching Frequency Motor Drive Using All Switching Patt...

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50th Annual Conference of the IEEE Industrial Electronics Society, IECON 2024

作者： Hayashi, Haru Yokokura, Yuki Ohishi, Kiyoshi Kobayashi, Yuto Hiwatari, Tenjiro Satake, Akira Department of Electrical Electronics and Information Engineering Nagaoka University of Technology Nagaoka Japan Advanced Technology R&D Center Mitubishi Electric Corporation Amagasaki Japan

ISBN: (纸本)9781665464543

This paper focuses on voltage-integral-based reference tracking modulation (VIrTM) and direct torque control (dTC), proposing the control strategy that minimizes switching frequency while achieving excellent dynamic performance. In the proposed scheme, the optimal voltage integral trajectory calculated by exhaustively searching all switching patterns in an offline process is applied to the dTC. One of the advantages of the proposed scheme is its superior versatility and robustness, as it does not rely on motor parameters. Secondly, it significantly reduces the switching frequency at all operating points while preserving the dynamic characteristics of dTC. The effectiveness of the proposed scheme has been validated through experiments, demonstrating up to a 28% reduction in switching frequency compared to conventional standard dTC. © 2024 IEEE.

关键词： Switching frequency

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Maximum Torque Per Ampere Operation for IPMSM Based on Sliding-Mode Extremum Seeking Control 16

Maximum Torque Per Ampere Operation for IPMSM Based on Slidi...

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16th IEEE PES Asia-Pacific Power and Energy engineering Conference, APPEEC 2024

作者： Wu, Xiang Zhang, Yuyang Ning, Cancan Chen, Shuo Ma, Zhixun School of Electrical Engineering China University of Mining and Technology Xuzhou China National Maglev Transportation Engineering R&d Center Tongji University Shanghai China

ISBN: (纸本)9798350386127

Aiming at the problem of poor robustness of model-based maximum torque per ampere (MTPA) algorithm, a sliding mode extremum search control based MTPA (SMESC-MTPA) method with d-axis current as search variables is proposed. SMESC-MTPA does not require either sinusoidal excitation signal or high-pass and low-pass filters to estimate the function gradient. Based on Lyapunov criterion, the stability of SMESC-MTPA is analyzed, and the convergence speed and control accuracy of the proposed algorithm are studied by analyzing the formation and switching process of sliding mode surface. The effectiveness of the proposed method is verified by simulation and experiment. © 2024 IEEE.

关键词： Low pass filters

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Experimental Verification of Circuit-Losses Analysis-Model of dC-Output Converter developed using Approximated Equations from Measurement data and datasheet data 14

Experimental Verification of Circuit-Losses Analysis-Model o...

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14th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2025

作者： Kondo, ryota Funaki, Tsuyoshi Mitsubishi Electric Corporation Advanced Technology R&d Center Hyogo Japan Osaka Univercity Division of Electric Electronics and Information Engineering Osaka Japan

ISBN: (纸本)9798331516116

This paper proposes a losses-analysis model of a dC-output converter based on the approximated equations from measurements and a datasheet. Target verification circuit consists of a dC-voltage source, a smooth capacitor, two half bridge legs, and a load inductor connected to the midpoints of the half bridge legs, which controls the continuous average dC current of the load inductor. The use of self-measured data, compared with the use of datasheet values, enables expanding the ranges of the considerable target parameters. Hence, lesser order approximated equations can deal with more target parameters with less calculation period than that in a conventional time domain simulation. In this study, calculation flow of losses from power devices losses and inductor losses to circuit losses was developed. Subsequently, a power losses model and inductor losses model were developed via the linear least square method. Finally, a 400 V experimental system was developed to verify the accuracy of the circuit losses at 16 specified operating conditions by varying three verification parameters, switching frequency, gate resistance, and inductance. The result shows that the losses calculated using the proposed model has good accuracy with an error of 1.9 % to 10.6 % to the measured result. © 2025 IEEE.

关键词： Bridge circuits

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