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Protection and Control of Modern Power Systems 2024年第4期9卷 110-125页

作者： Hao Wang Li Zhang youliang sun Liang Zou the School of Electrical Engineering Shandong Uni-versityJinan 250061China the School of Electrical Engineering Shandong UniversityJinan 250061China Shandong Power Equipment Co. Ltd.Jinan 250101China

To clarify the electromagnetic,vibration,and loss characteristics of the internal components of a converter transformer under DC bias conditions and their influencing mechanisms,a series of studies are conducted using the finite element method and model *** paper quantifies the influence of different DC contents on the magnetic flux density,force,and displacement distribution characteristics of the iron core and winding and analyzes the internal relationship between various *** inflection point of the DC bias coefficient on the vibration is obtained and the contribution mechanism of the different responses of the iron core and winding to this inflection point is *** value of the DC bias coefficient for changing the main vibration frequency is *** the DC bias coefficient is 1.0 and 1.5,the main frequency of vibration moves to the right to 250 Hz and 350 *** on the principle of similarity,a DC bias vibration experimental platform for converter transformers is developed,and DC bias magnetic experiments are conducted to verify the reliability of the simulation results.

关键词： DC bias converter transformer finite element and experimental analysis

Skull bone tumor:a review of clinicopathological and neuroimaging characteristics of 426 cases at a single center

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Cancer Communications 2019年第1期39卷 67-71页

作者： Hailong Liu Xueying Zhang Mingshan Zhang Junping Zhang Weihai Ning Angela Yue Rugang Zhao youliang sun Chunjiang Yu Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityNo.50 Yikesong RoadXiangshan AveBeijing 100093P.R.China Department of Neurosurgery Chinese People’s Liberation Army General HospitalBeijing 100853P.R.China School of Public Health Peking UniversityBeijing 100191P.R.China Tate Cancer Center Baltimore Washington Medical CenterUniversity of MarylandGlen BurnieMD 21061USA Department of Orthopedics Beijing Ditan HospitalCapital Medical UniversityBeijing 10015P.R.China School of Basic Medical Science Capital Medical UniversityBeijing 10069P.R.China

Dear Editor,Among the wide array of human neoplasms,bone and soft tissue tumors originating from the skull bone are extremely rare,making up<2%of all the musculoskeletal tumors[1].Skull bone tumors exist as a distinct entity because they include multiple subtypes,have complex regional anatomical structure,and require interdiscipli-nary *** to the 2002 world health organi-zation(WHO)histological typing[2],skull bone tumors can be divided into benign,malignant,and undefined neoplastic nature tumors(UNNTs).Given the lack of literatures systematically reporting this uncommon dis-order and the small-scale sample size published studies on these tumor entities[3,4],a deeper understanding of the clinicopathological features across skull bone tumor is ***,therefore,conducted this retrospective analysis on bony tumor spectrum involving the primary and secondary lesions arising from the skull to document the various types of tumors encountered,and to analyze their epidemiological characteristics,clinicopathogical features and neuroradiographic parameters.

关键词： neoplasms clinic pathological

Inhibition of gasdermin D-dependent pyroptosis attenuates the progression of silica-induced pulmonary inflammation and fibrosis

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Acta Pharmaceutica Sinica B 2022年第3期12卷 1213-1224页

作者： Meiyue Song Jiaxin Wang youliang sun Junling Pang Xiaona Li Yuan Liu Yitian Zhou Peiran Yang Tianhui Fan Ying Liu Zhaoguo Li Xianmei Qi Baicun Li Xinri Zhang Jing Wang Chen Wang State Key Laboratory of Medical Molecular Biology Department of PhysiologyInstitute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100730China Tsinghua-Peking Center for Life Sciences Department of BiologyCollege of MedicineTsinghua UniversityBeijing 100084China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship HospitalBeijing 100029China National Clinical Research Center for Respiratory Diseases Beijing 100029China Peking Union Medical College Chinese Academy of Medical SciencesBeijing 100730China Peking Union Medical College MD ProgramBeijing 100730China Department of Respiratory the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China Department of Pulmonary and Critical Care Medicine the First Hospital of Shanxi Medical UniversityTaiyuan 030001China

Silicosis is a leading cause of occupational disease-related morbidity and mortality worldwide,but the molecular basis underlying its development remains *** accumulating body of evidence supports gasdermin D(GSDMD)-mediated pyroptosis as a key component in the development of various pulmonary ***,there is little experimental evidence connecting silicosis and GSDMD-driven *** this work,we investigated the role of GSDMD-mediated pyroptosis in ***-cell RNA sequencing of healthy and silicosis human and murine lung tissues indicated that GSDMD-induced pyroptosis in macrophages was relevant to silicosis *** microscopy we then observed morphological alterations of pyroptosis in macrophages treated with *** of interleukin-1βrelease,lactic dehydrogenase activity,and real-time propidium iodide staining further revealed that silica induced pyroptosis of ***,we verified that both canonical(caspase-1-mediated)and non-canonical(caspase-4/5/11-mediated)signaling pathways mediated silica-induced pyroptosis activation,in vivo and in ***,Gsdmd knockout mice exhibited dramatically alleviated silicosis phenotypes,which highlighted the pivotal role of pyroptosis in this *** together,our results demonstrated that macrophages underwent GSDMD-dependent pyroptosis in silicosis and inhibition of this process could serve as a viable clinical strategy for mitigating silicosis.

关键词： Silicosis Gasdermin D Pyroptosis Macrophage Pulmonary fibrosis

Analysis of Non-Sinusoidal Steady Electric Field of ±500 kV Converter Transformer

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Energy and Power Engineering 2017年第4期9卷 53-62页

作者： Gang Liu Cheng Chi Yanjiao Jin Yongqiang Ma Lipeng sun Lin Li youliang sun Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power Universi-ty Baoding China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing China Shandong Power Equipment Co. Ltd. Jinan China

The line side winding is under the fundamental frequency AC voltage, while the valve side winding contains not only fundamental AC voltage component, but also the DC voltage component, fundamental AC voltage component, and higher harmonic voltage components when the converter transformer is at its normal operating condition, and the electric field of converter transformer is a non-sinusoidal steady one. To analyze the non-sinusoidal steady electric field containing the DC component, fundamental AC and higher harmonic components, the voltage spectrum of the valve winding in a ±500 kV converter transformer is firstly analyzed, and the non-sinusoidal periodic steady electric field is obtained by the fast discrete Fourier transform. Different resistivity of the oil and oil-immersed paper is adopted to simulate the aging of oil paper insulation at operation, and get the non-sinusoidal steady electric field.

关键词： Converter Transformer AC-DC Hybrid Non-Sinusoidal Periodic Electric Field

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直流GIL中线形金属微粒电动力学行为研究

电工技术学报 2021年第24期36卷 5283-5293页

作者：程涵魏威 Bilal lqbal Ayubi 孙优良张黎山东大学电气工程学院济南250061

直流GIL中线形金属微粒受力运动极易引发气体间隙击穿或者绝缘子沿面闪络,降低GIL的绝缘性能,严重影响直流输电系统的安全可靠运行。为研究直流GIL中线形金属导电微粒电动力学行为机理,搭建自由微粒实验装置和观测平台,并建立直流下微... 详细信息

直流GIL中线形金属微粒受力运动极易引发气体间隙击穿或者绝缘子沿面闪络,降低GIL的绝缘性能,严重影响直流输电系统的安全可靠运行。为研究直流GIL中线形金属导电微粒电动力学行为机理,搭建自由微粒实验装置和观测平台,并建立直流下微粒电动力学模型。通过实验与仿真相结合的方法,获得线形金属微粒荷电特性、启举与运动特性以及微粒运动导致的气隙击穿特性,并从微观角度解释了微粒启举与运动现象形成的原因。研究结果表明,线形启举电压只与半径有关,与长度和电压极性无关,随着半径增大,启举电压升高,直流电压极性不影响金属微粒启举电压幅值;线形微粒的运动及导致的气隙击穿与微粒半径、长度和电压极性有关,线形金属微粒半径小、长度增加时容易导致气隙击穿;线形金属微粒形状的不规则使得电场畸变作用加强,极性效应更明显。电晕极性效应导致正负极性下线形微粒的启举与运动及运动致气隙击穿特性呈现出明显的规律,当达到启举电压时,正极性下,线形金属微粒一端抬起后,在下极板小幅跳跃、旋转或者直立,难以贯穿气隙;负极性下,线形金属微粒贯穿气隙运动,极易出现飞萤现象,为直流GIL中线形金属微粒污染防治提供了理论指导。

关键词：直流GIL 线形金属微粒电动力学行为启举运动

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一种改进的柔性直流系统IGBT行为模型

电工技术学报 2021年第S01期36卷 200-208页

作者：宋鹏程张黎邹亮赵彤孙优良山东大学电气工程学院济南250061

在柔性直流换流站中,换流阀中绝缘栅双极型晶体管(IGBT)的开关暂态过程是产生电磁干扰的重要原因之一,这些高频的电磁干扰会对换流站内关键设备的正常运行产生不利的影响。目前,在IGBT开关暂态过程建模中普遍采用行为模型,该模型虽然在... 详细信息

在柔性直流换流站中,换流阀中绝缘栅双极型晶体管(IGBT)的开关暂态过程是产生电磁干扰的重要原因之一,这些高频的电磁干扰会对换流站内关键设备的正常运行产生不利的影响。目前,在IGBT开关暂态过程建模中普遍采用行为模型,该模型虽然在仿真速度、通用性等方面有很大优势,但却存在仿真精度较低等缺点。针对现有行为模型的不足,该文提出一种基于矢量匹配法的改进行为模型,利用矢量匹配法这种高效稳定的有理函数拟合方法对行为模型中仿真精度较低阶段的波形进行拟合,并将拟合后的公式在时域内等效为简单电路的形式,然后与传统行为模型相结合,得到更加精确的IGBT暂态模型。最后,该文在仿真软件中搭建改进的行为模型,并进行仿真波形与实验波形的对比与误差分析,结果证明所提出模型精度较传统模型有较大的提高。

关键词：柔性直流输电绝缘栅双极型晶体管(IGBT) 矢量匹配行为模型

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换流变压器极性反转试验的数值模拟

中国电机工程学报 2011年第18期31卷 107-112页

作者：李琳纪锋李文平孙优良刘刚华北电力大学电气与电子工程学院河北省保定市071003 保定天威保变电气股份有限公司河北省保定市071056

换流变压器绝缘结构中的油浸纸、纸板的电导率呈各向异性、非线性特性。从利用罚函数法获得的有限元状态方程出发,应用龙格库塔法对状态方程进行求解,计算了一个实际换流变压器模型在极性反转试验电压下绝缘结构中瞬态电场的变化。计算... 详细信息

换流变压器绝缘结构中的油浸纸、纸板的电导率呈各向异性、非线性特性。从利用罚函数法获得的有限元状态方程出发,应用龙格库塔法对状态方程进行求解,计算了一个实际换流变压器模型在极性反转试验电压下绝缘结构中瞬态电场的变化。计算结果表明,各向异性非线性媒质中的电场分布与各向同性线形媒质中的电场分布有很大不同。为了准确的进行换流变压器绝缘结构设计,需要考虑媒质的各向异性非线性特性。

关键词：换流变压器各向异性非线性有限元龙格库塔法极性反转试验

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基于响应面法的变压器静电环绝缘优化设计

高电压技术 2022年第10期48卷 4163-4171页

作者：刘刚刘西娅刘尧李琳孙优良雷园园华北电力大学河北省输变电设备安全防御重点实验室保定071003 华北电力大学电力工程系保定071003 山东电力设备有限公司济南250022 南方电网科学研究院有限责任公司广州510663

绝缘裕度是变压器设计中重要指标之一,合适的绝缘裕度值可以保证变压器运行中不会发生主绝缘问题。为此以绝缘裕度为优化目标,首先采用ANSYS参数化建模语言(ANSYS parametric design language,APDL)完成对变压器的建模剖分求解,利用全... 详细信息

绝缘裕度是变压器设计中重要指标之一,合适的绝缘裕度值可以保证变压器运行中不会发生主绝缘问题。为此以绝缘裕度为优化目标,首先采用ANSYS参数化建模语言(ANSYS parametric design language,APDL)完成对变压器的建模剖分求解,利用全域扫描法获得变压器的绝缘裕度值;然后根据中心复合设计法开展试验,采用响应面法构建绝缘裕度系数与其相关变量的响应面函数,最后利用数学规划法,求得此函数在各变量相互配合下的最优解。优化后的绝缘裕度比优化前提高了16.53%。为了验证响应面法的有效性,采用遗传算法对绝缘结构进行优化,结果验证了响应面法的有效性。相比于全局寻优方法,响应面法在保证精度的同时提高了优化效率,可为变压器绝缘设计提供参考。

关键词：绝缘裕度 APDL 响应面法结构优化变压器