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Period–Luminosity Relationship forδScuti Stars Revisited
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作者 Atila Poro S.Javad Jafarzadeh +7 位作者 Roghaye Harzandjadidi Mohammad Madani Elnaz Bozorgzadeh Esfandiar Jahangiri Ahmad Sarostad Ailar Alizadehsabegh Maryam Hadizadeh Mohammad EsmaeiliVakilabadi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期138-143,共6页
The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375δScuti stars from the ASAS catalog.The selected stars have a variety of observational characteristics,with a higher than 80%probabili... The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375δScuti stars from the ASAS catalog.The selected stars have a variety of observational characteristics,with a higher than 80%probability of beingδScuti stars.We have displayed all the stars in the Hertzsprung-Russell diagram along with theδScuti instability strip,the Zero Age Main Sequence and the Terminal Age Main Sequence.Then,we determined which fundamental and overtone modes each star belongs to using pulsation constant(Q)calculations.In addition,we evaluated the parameters in the Q calculation equation using three machine learning methods,which showed that surface gravity and temperature have the greatest effect on its calculation.The Period-Luminosity(P-L)relationship of theδScuti stars was also revisited.Eventually,using least squares linear regression,we made four linear fits for fundamental and overtone modes and updated their relationships. 展开更多
关键词 starS VARIABLES delta Scuti--stars fundamental parameters-methods data analysis
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Pulsation Analysis of High-AmplitudeδScuti Stars with TESS
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作者 薛王俊婷 牛家树 +1 位作者 薛会芳 银思静 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第7期15-24,共10页
In this work,the pulsation analysis is performed on 83 high-amplitudeδScuti stars(HADS),which have been observed by the Transiting Exoplanet Survey Satellite.The results show that 49 of these HADS show single-mode pu... In this work,the pulsation analysis is performed on 83 high-amplitudeδScuti stars(HADS),which have been observed by the Transiting Exoplanet Survey Satellite.The results show that 49 of these HADS show single-mode pulsation,27 of them show radial double-modes pulsation(in which 22 of them pulsate with the fundamental and first overtone modes and five of them pulsate with the first and second overtone modes),and seven of them show radial triple-modes pulsation(three of which are newly confirmed triple-mode HADS).The histogram of the fundamental periods and the ratios between the fundamental and first overtone periods show bimodal structures,which might be caused by the stellar evolution in this specific phase.Most of the radial triple-mode HADS have a fundamental amplitude of 41-54 mmag,and 50%of them have similar amplitudes of the fundamental and first overtone pulsation modes.All these hints require further confirmation not only in observations with more HADS samples,but also in theoretical models with suitable treatments of stellar evolution and pulsation. 展开更多
关键词 stars:variables:delta Scuti stars:oscillations(including pulsations) stars:evolution
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星-三角接法的分数槽永磁电机匝间短路故障分析 被引量:1
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作者 陈浈斐 凌志豪 +2 位作者 范晨阳 李志新 万向民 《电力自动化设备》 EI CSCD 北大核心 2024年第1期181-187,共7页
为了分析永磁电机绕组采用星-三角(Y-△)接法时发生匝间短路故障后对电机的影响,建立了绕组在Y-△接法下分别在星形(Y)接法部分和角形(△)接法部分发生匝间短路故障的电路模型,推导得到故障发生后电机三相电流。以10极12槽永磁电机为例... 为了分析永磁电机绕组采用星-三角(Y-△)接法时发生匝间短路故障后对电机的影响,建立了绕组在Y-△接法下分别在星形(Y)接法部分和角形(△)接法部分发生匝间短路故障的电路模型,推导得到故障发生后电机三相电流。以10极12槽永磁电机为例进行二维有限元仿真,对传统的Y接法双层绕组永磁电机和Y-△接法4层绕组永磁电机发生匝间短路故障的情况进行对比分析。仿真结果表明:在Y-△接法下匝间短路故障位置的不同对电流会有很大影响;在发生匝间短路故障后Y-△接法能降低电机的转矩脉动,降低故障发生后故障相电流中的3次谐波幅值。 展开更多
关键词 永磁电机 匝间短路 短路电流 星-三角接法 4层绕组
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Y-Δ接法分数槽永磁电机断相故障电流特征分析与诊断方法研究
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作者 陈浈斐 王枫 +2 位作者 李志新 万向民 凌志豪 《中国电机工程学报》 EI CSCD 北大核心 2024年第21期8653-8662,I0027,共11页
星-三角(Y-△)接法的分数槽永磁电机(fractional-slot permanent magnet machine,FS-PMM)因其谐波分量低、转矩脉动小等优点在电动汽车领域具有较好的应用前景。但由于该电机中的△接绕组位于电机内部,其电流无法直接测量,故障时难以被... 星-三角(Y-△)接法的分数槽永磁电机(fractional-slot permanent magnet machine,FS-PMM)因其谐波分量低、转矩脉动小等优点在电动汽车领域具有较好的应用前景。但由于该电机中的△接绕组位于电机内部,其电流无法直接测量,故障时难以被及时发现。该文针对Y-△接法的FS-PMM内层△接绕组单相断相故障,提出一种基于电流三次谐波幅值的故障诊断方法。首先,建立△接绕组单相断相故障下的数学模x相故障的检测与故障相定位。经实验验证,所提方法能够实时准确地实现△接绕组单相断相故障诊断,且具有良好的鲁棒性。 展开更多
关键词 星-三角接法 分数槽永磁电机 断相故障 电流特征 故障诊断方法
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基于星三角启动电路的测控课程教学思考
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作者 姚建南 《教育教学论坛》 2024年第15期141-144,共4页
基于传统的星三角降压启动电路,分析了星三角降压启动电路的原理、使用条件,针对75 kW电机的星三角降压启动电路的选型计算案例,详细计算了三相绕组星形连接和三角形连接时的相电压、线电压、相电流和线电流,得出了主接触器、星接触器... 基于传统的星三角降压启动电路,分析了星三角降压启动电路的原理、使用条件,针对75 kW电机的星三角降压启动电路的选型计算案例,详细计算了三相绕组星形连接和三角形连接时的相电压、线电压、相电流和线电流,得出了主接触器、星接触器和角接触器的选型依据,并对比分析确定了星三角降压启动的最优电路图。进一步结合案例分析,在“工程专业认证”视域下,讨论了有关知识传授、问题分析、提出方案、职业规范和成本控制等一系列测控课程教学思考,以期提高学生解决复杂工程问题的能力。 展开更多
关键词 星三角启动电路 选型计算 测控课程 教学思考
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基于参数优化VMD和多尺度模糊熵的星-三角接法FS-PMM匝间短路故障诊断方法
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作者 陈浈斐 凌志豪 +1 位作者 李志新 包淼 《电机与控制应用》 2024年第6期31-43,共13页
星-三角(Y-Δ)接法多层绕组结构可以抑制分数槽永磁电机电枢磁场的低次谐波磁动势,提高电机运行效率。但其结构较常规Y接法双层绕组结构更为复杂,发生匝间短路的风险更高。首先,建立Y-Δ接法分数槽永磁电机(FS-PMM)发生匝间短路的电路模... 星-三角(Y-Δ)接法多层绕组结构可以抑制分数槽永磁电机电枢磁场的低次谐波磁动势,提高电机运行效率。但其结构较常规Y接法双层绕组结构更为复杂,发生匝间短路的风险更高。首先,建立Y-Δ接法分数槽永磁电机(FS-PMM)发生匝间短路的电路模型,推导出故障发生后电机三相电流,分析出三相故障电流会受匝间短路位置的影响。其次,利用自适应权重和柯西-高斯变异策略对鲸鱼捕食优化算法进行改进,用于优化变分模态分解参数,提出一种参数优化的变分模态分解算法对电流信号进行处理。最后,通过计算电流和电磁转矩的多尺度模糊熵,提出Y-Δ接法FS-PMM匝间短路故障诊断方法。该方法故障诊断准确率达到95%以上,并可以对Y接法部分和Δ接法部分的匝间短路故障进行有效区分。 展开更多
关键词 星-三角接法 分数槽永磁电机 匝间短路 改进鲸鱼捕食算法 多尺度模糊熵 故障诊断
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变频启动切换工频运行的控制原理解析
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作者 林志刚 《变频器世界》 2024年第9期76-78,共3页
本文分析了变频启动切换至工频运行的应用背景,例举了中央空调压缩机电机的变频启动后工频运行的方案,通过计算、仿真的手段对变频启动切换工频运行的切换电流数据进行分析,最后总结得出用变频器启动后切换至工频运行控制原理特点以及... 本文分析了变频启动切换至工频运行的应用背景,例举了中央空调压缩机电机的变频启动后工频运行的方案,通过计算、仿真的手段对变频启动切换工频运行的切换电流数据进行分析,最后总结得出用变频器启动后切换至工频运行控制原理特点以及注意事项。 展开更多
关键词 软启动器 星-三角 变频器 工频 切换电流
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V2551 Cyg:a pulsating star with enigmatic peculiarities
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作者 Diana P.Kjurkchieva Velimir A.Popov +2 位作者 Dragomir V.Marchev Kenneth T.Menzies Nikola I.Petrov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第7期57-66,共10页
Intensive photometric and spectral observations of the variable star V2551 Cyg are presented.The light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing b... Intensive photometric and spectral observations of the variable star V2551 Cyg are presented.The light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing binary. The period and amplitude of the light curve, the amplitudes of color changes and the radial velocity curve of V2551 Cyg are similar to those of a high-amplitude δ Scuti variable. The target seems to pulsate with the fundamental mode. However, V2551 Cyg exhibits several important peculiarities:(i) the decreasing branch of its light curve is steeper than the increasing one;(ii) the radial velocity curve has a flat section in the phase range 0.7-1.2 and short increase of the negative radial velocity at phase 0.7;(iii) the rotational velocity is quite big for a HADS star;(iv) the Fourier coefficients of V2551 Cyg are quite different from those of HADS stars. The target classification is difficult due to these peculiarities. 展开更多
关键词 starS VARIABLES delta Scuti - stars VARIABLES RR Lyrae - stars individual (V2551 Cyg)
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Precise Evolutionary Asteroseismology of High-AmplitudeδScuti Star AE Ursae Majoris
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作者 Hui-Fang Xue Jia-Shu Niu Jian-Ning Fu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第10期61-76,共16页
Stellar structure and evolution theory is one of the bases in modern astronomy.Stellar inner structures and their evolutionary states can be precisely tested by asteroseismology,since the inner information is brought ... Stellar structure and evolution theory is one of the bases in modern astronomy.Stellar inner structures and their evolutionary states can be precisely tested by asteroseismology,since the inner information is brought to the stellar surface by the global oscillating waves and becomes observable.For stellar evolutionary speed(i.e.,how long timescale does a star stay at a special evolution phase?),because of the insurmountable gap between the timescales of the evolutionary history of human civilization and a star,it can only be roughly tested by ensemble of stars in different evolutionary stages in most cases,and all the snapshots of these stars make up our global view of stellar evolution.The effect of stellar evolution on the structure and the corresponding global size of a pulsating star will lead to tiny period variations of its pulsation modes,which are the most valuable indicators of its evolutionary state and can be used to test the stellar evolution theory by a single star rather than ensemble of stars.Here,we report a High-AmplitudeδScuti star AE Ursae Majoris,which is located in the post main-sequence(MS)evolutionary stage and its observed linear period variation rate can be practically ascribed to its evolutionary effect.The result tests the stellar evolution theory from the pre-MS to post-MS with an unprecedented precision by a single star,and the framework can be extended to other type of pulsating stars to perform precise evolutionary asteroseismology,which aims to test the current stellar evolution theory in different evolutionary stages,discover the discrepancies between the theory and observations,and ultimately build a complete and precise stellar evolution theory to backtrack the history of each of these stars. 展开更多
关键词 starS VARIABLES delta Scuti-stars evolution-stars oscillations(including pulsations)
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■ Condensation in Neutron Star Matter with △ Quartet
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作者 丁文波 刘广洲 +3 位作者 朱明枫 喻孜 许妍 赵恩广 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期500-508,共9页
In the framework of relativistic mean field theory, the condensations of K^- and K^0 in neutron star matter including baryon octet and △ quartet are studied. We find that in this case K^- and K^0 condensations can oc... In the framework of relativistic mean field theory, the condensations of K^- and K^0 in neutron star matter including baryon octet and △ quartet are studied. We find that in this case K^- and K^0 condensations can occur at relative shallow optical potential depth of K^ from -80 MeV to -160 MeV. Both K^- and K^0 condensations favor the appearances of △ resonances. With K^- condensations all the △ quartet can appear well inside the maximum mass stars. The appearances of △ resonances change the composition and distribution of particles at high densities. The populations of △ resonances can enhance K^- condensation. It is found that in the core of massive neutron stars, neutron star matter includes rich particle species, such as antikaons, baryon octet, and △ quartet. In the presence of △ resonances and K^- condensation, the EOS becomes softer and results in smaller maximum mass stars. Furthermore the impact of antikaon condensations, hyperons, and △ resonances on direct Urca process with nucleons is also discussed briefly. 展开更多
关键词 antikaon condensation neutron stars delta resonances
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Candidate Eclipsing Binary Systems with aδScuti Star in Northern TESS Field
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作者 F.Kahraman Aliçavuş D.Gümüş +4 位作者 Ö.Kırmızıtaş Ö.Ekinci S.Çavuş Y.T.Kaya F.Aliçavuş 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第8期34-48,共15页
The existence of pulsating stars in eclipsing binaries has been known for decades.These types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation variations.Th... The existence of pulsating stars in eclipsing binaries has been known for decades.These types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation variations.The eclipsing binaries are the only way to directly measure the mass and radius of stars with a good accuracy(≤1%),while the pulsations are a unique way to probe the stellar interior via oscillation frequencies.There are different types of pulsating stars existing in eclipsing binaries.One of them is theδScuti variables.Currently,the known number ofδScuti stars in eclipsing binaries is around 90 according to the latest catalog of these variables.An increasing number of these kinds of variables is important to understand the stellar structure,evolution and the effect of binarity on the pulsations.Therefore,in this study,we focus on discovering new eclipsing binaries withδScuti component(s).We searched within the northern Transiting Exoplanet Survey Satellite(TESS)field with a visual inspection by following some criteria such as light curve shape,the existence of pulsation like variations in the out-of-eclipse light curve and the T_(eff) values of the targets.As a result of these criteria,we discovered some targets.The orbital variations were first removed from the TESS light curves and frequency analysis was performed on the residuals.The luminosity,and absolute and bolometric magnitudes of the targets were calculated as well.To find how much of these parameters represent the primary(more luminous)binary component,we also computed the flux density ratio of the systems by utilizing the area of the eclipses.In addition,the positions of the systems in the H-R diagram were examined considering the flux density ratios.As a consequence of the investigation,we defined 38 candidateδScuti stars and also one Maia variable in eclipsing binary systems. 展开更多
关键词 (stars:)binaries:eclipsing stars:variables:delta Scuti techniques:photometric
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Search for variable stars in the open cluster NGC 1245
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作者 Dong-Xiang Shen Yu Zhang +5 位作者 Chun-Yan Li Xiang-Yun Zeng Guo-Liang Lv Chun-Hua Zhu Qing-Shun Hu Jin-Zhong Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第5期223-234,共12页
We used the Nanshan 1 m telescope of Xinjiang Astronomical Observatory to investigate variable stars in the region of NGC 1245. We detected 55 variable stars in the field of view, 42 of them are newly discovered: six ... We used the Nanshan 1 m telescope of Xinjiang Astronomical Observatory to investigate variable stars in the region of NGC 1245. We detected 55 variable stars in the field of view, 42 of them are newly discovered: six binaries, 22 pulsating stars, 14 unclassified variables. We discussed the physical properties and classifications of the variable stars through their light curves. The cross-matching with the members catalog of NGC 1245 suggests that 10 variable stars are identified as probable cluster members, which including one EW type binary, eight δ Scuti stars, and an unknown type variable star. Since the difference of the members catalog of the cluster and the limitations of the instrument, there are some huge differences in the variable list of NGC 1245 compared with the previous work. 展开更多
关键词 open clusters and associations:individual(NGC 1245) stars:variables:general stars:variables:delta Scuti binaries:eclipsing
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Variability Study of the SX Phoenicis Star BL Camelopardalis
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作者 Jian-Ning Fu Chao Zhang +3 位作者 Kanokwan Marak Chayan Boonyarak PongsakKhokhuntod Shi-Yang Jiang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第2期237-244,共8页
New time-series photometric observations of BL Cam in the V band and white light were made during 2005 to 2007 at the Xinglong Station of China. The frequency analysis confirms two closely separated frequencies, 25.18... New time-series photometric observations of BL Cam in the V band and white light were made during 2005 to 2007 at the Xinglong Station of China. The frequency analysis confirms two closely separated frequencies, 25.181 d^-1 and 25.571 d^-1, but the frequency of 31-32 d^- 1 reported in the literature was not detected in the new data. New times of maximum light were determined from both our light curves and those available on Internet, allowing a more comprehensive study of the O - C diagram, together with the times of maximum light in the literature. A new interpretation, including the period increasing before 1988 and decreasing since 1992 of BL Cam and the light-time effect in a binary system, looks plausible. 展开更多
关键词 techniques: photometric -- stars: variables: delta Scuff -- stars: individual: BL Cam
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不间断式星三角起动的建模与仿真
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作者 谢芳芳 李明飞 +1 位作者 张莱 谭雨祺 《湖南工业职业技术学院学报》 2023年第6期10-14,共5页
对电机起动过程进行建模与仿真是电机及其系统研究的重要基础。本文分析了笼型电机不间断式星三角起动的过程,将起动过程分为四个阶段,利用Matlab/Simscape工具搭建不间断式星三角起动的仿真模型,研究了两种典型电机的星三角起动的动态... 对电机起动过程进行建模与仿真是电机及其系统研究的重要基础。本文分析了笼型电机不间断式星三角起动的过程,将起动过程分为四个阶段,利用Matlab/Simscape工具搭建不间断式星三角起动的仿真模型,研究了两种典型电机的星三角起动的动态过程。结果表明,与普通的间断式星三角起动相比,不间断式星三角起动能有效减小最大冲击电流,转矩与转速的脉动幅度更小,为电机高性能驱动和保护系统的深入研究提供了有效模型和依据。 展开更多
关键词 星三角起动 笼型电机 建模与仿真 Matlab/Simscape
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笼型电动机闭式星三角启动的仿真研究
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作者 谢芳芳 刘良斌 邹序武 《价值工程》 2023年第19期103-105,共3页
针对笼型电动机的闭式星三角启动,在分析启动过程的基础上,利用MATLAB/Simulink搭建闭式星三角启动的仿真模型,通过仿真深入研究星三角启动的动态过程。仿真结果表明,与普通的开式星三角启动相比,闭式星三角启动的电源线电流冲击幅度降... 针对笼型电动机的闭式星三角启动,在分析启动过程的基础上,利用MATLAB/Simulink搭建闭式星三角启动的仿真模型,通过仿真深入研究星三角启动的动态过程。仿真结果表明,与普通的开式星三角启动相比,闭式星三角启动的电源线电流冲击幅度降低45.71%,电磁转矩脉动幅度降低41.75%,转速脉动幅度降低40%,为电机驱动系统的深入研究提供了有效模型和依据。 展开更多
关键词 星三角启动 笼型电动机 建模与仿真 MATLAB/SIMULINK
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东非裂谷盆地浅水三角洲储层星型丛式水平井网渗流规律及参数优化
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作者 杨莉 刘广为 +1 位作者 杨宝泉 刘钧 《中国海上油气》 CAS CSCD 北大核心 2023年第3期96-102,共7页
东非裂谷盆地Albert湖区X油田为浅层层状砂岩油藏,主力储层为浅水三角洲沉积,综合考虑钻井难度及储层条件,开发方案采用了星型丛式水平井注采井网结构。根据势叠加理论,建立了典型星型井网的渗流模型,分析了星型井网的势分布特征;通过... 东非裂谷盆地Albert湖区X油田为浅层层状砂岩油藏,主力储层为浅水三角洲沉积,综合考虑钻井难度及储层条件,开发方案采用了星型丛式水平井注采井网结构。根据势叠加理论,建立了典型星型井网的渗流模型,分析了星型井网的势分布特征;通过典型模型数值模拟,分析了星型井网水平井段沿程产出特征,并进一步对星型水平井网参数优化进行了分析。结果表明,适当减小注水井射孔段长度、生产井采用智能完井、井网中部加密1口直井,均可以改善星型井网开发效果。X油田所采用的星型丛式水平井注采井网结构设计思路,可以为其他相似油田提供参考。 展开更多
关键词 星型井网 丛式水平井 浅水三角洲 渗流规律 参数优化
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长三角一体化背景下六安市“月牙”形城市团发展构想
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作者 孟祥林 《青岛科技大学学报(社会科学版)》 2023年第2期10-17,共8页
六安市在融入长三角城市体系的过程中,需要通过“月牙”形发展构架将腹地内的县级中心地整合在一起,在每个县域腹地内需要按照“分区+分步”发展秩序整合乡镇中心地构建微中心,并将发展基础好的微中心发展成为县级中心地的副中心。可在... 六安市在融入长三角城市体系的过程中,需要通过“月牙”形发展构架将腹地内的县级中心地整合在一起,在每个县域腹地内需要按照“分区+分步”发展秩序整合乡镇中心地构建微中心,并将发展基础好的微中心发展成为县级中心地的副中心。可在六安市与周边区域中心城市中建立“大”+枣核形的格局,形成安徽省西端构建跨行政区划城市体系的纽带。进一步完善城市链,同时以乡镇中心地为基础构建次级城市团,奠定以六安市主城区为核心构建多层次城市体系的基础。六安市具有与合肥市协同发展的区位优势,要前瞻性地考虑与阜阳市、淮南市、安庆市整合,在安徽省中部西端构建城市化的增长点。 展开更多
关键词 长三角一体化 “月牙”形城市团 “分区+分步” “大”+枣核形 次级城市团
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电动机全压起动的条件验证
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作者 张凯超 罗刚 陈姝君 《电气开关》 2023年第6期58-59,63,共3页
本文探讨了电动机全压起动的条件。通过实际工程分析、计算电动机全压起动时母线电压相对值、调整电动机功率与变压器容量比值,对判定电动机全压起动的常用方法进行验证。结果表明,全压起动接线简单、维护方便,是最安全、快捷的气动方... 本文探讨了电动机全压起动的条件。通过实际工程分析、计算电动机全压起动时母线电压相对值、调整电动机功率与变压器容量比值,对判定电动机全压起动的常用方法进行验证。结果表明,全压起动接线简单、维护方便,是最安全、快捷的气动方式。如无其他条件限制,当电动机功率不大于变压器容量的30%时,电动机理应直接选择全压起动。 展开更多
关键词 电动机 全压起动 星-三角起动 电动机起动 母线电压 电压暂降
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星形和三角形连接的链式H桥STATCOM不平衡补偿分析 被引量:28
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作者 季振东 孙毅超 +2 位作者 李东野 赵剑锋 黄允凯 《高电压技术》 EI CAS CSCD 北大核心 2015年第7期2435-2444,共10页
基于星形和三角形结构的链式H桥STATCOM各具优势,但目前仍没有量化的指标来衡量各自的不平衡补偿能力,限制了其应用以及选型。为了更好地使用两种结构,从三相之间的直流侧平衡问题出发,分析了两种结构各自具有的负序电流补偿特点,从理... 基于星形和三角形结构的链式H桥STATCOM各具优势,但目前仍没有量化的指标来衡量各自的不平衡补偿能力,限制了其应用以及选型。为了更好地使用两种结构,从三相之间的直流侧平衡问题出发,分析了两种结构各自具有的负序电流补偿特点,从理论上确定了各自的应用场合。对于星形结构,选用零序电压注入法进行直流侧相间平衡控制,并提出利用三相中最大输出电压来衡量其负序电流补偿能力;对于三角形结构,证明了分相控制法和零序电流注入法是等效的,并推导出其负序电流补偿范围。通过仿真验证了各自的负序电流补偿特性,进一步明确了星形结构更适合电流不平衡度较小的场合。这些量化分析对两种结构的应用和选型具有指导作用。 展开更多
关键词 直流侧电压平衡 级联STATCOM 星形连接 三角形连接 负序电流补偿 不平衡补偿
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与△/Y_0变压器相联的同步发电机暂态运行时步有限元仿真 被引量:6
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作者 蒙亮 刘晓芳 罗应立 《电网技术》 EI CSCD 北大核心 2004年第13期36-39,64,共5页
结合时步有限元方法,设计了一个通过△/Y0变压器与无穷大系统及负荷相连接的同步发电机暂态运行过程的仿真程序。在该仿真程序中的发电机模型中考虑了铁心的饱和、转速的变化以及自动电压调节系统(AVR)的调节等对仿真结果的影响,并应用... 结合时步有限元方法,设计了一个通过△/Y0变压器与无穷大系统及负荷相连接的同步发电机暂态运行过程的仿真程序。在该仿真程序中的发电机模型中考虑了铁心的饱和、转速的变化以及自动电压调节系统(AVR)的调节等对仿真结果的影响,并应用了麦克斯韦应力法计算电磁力矩。在仿真计算中,通过改变仿真程序中相应的参数来模拟不同线路上开关的断开、闭合过程,能方便地对同步发电机受到多种三相对称干扰后的运行过程进行有限元数字仿真。算例计算结果表明了该仿真程序的正确性。 展开更多
关键词 同步发电机 暂态运行 时步有限元方法 仿真 △/Yo变压器 电力系统 仿真模型
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