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Rotational Deformation of Neutron Stars

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Chinese Physics Letters 2005年第7期22卷 1604-1607页

作者：文德华陈伟刘良钢 DepartmentofPhysics SouthChinaUniversityofTechnologyGuangzhou510641 DepartmentofPhysics JinanUniversityGuangzhou510632_ DepartmentofPhysics ZhongshanUniversityGuangzhou510275

The rotational deformations of two kinds of neutron stars are calculated by using Hartle's slow-rotation formulism. The results show that only the faster rotating neutron star gives an obvious deformation. For the slo... 详细信息

关键词： tov TNS HS

Suitable resolution of EOS tables for neutron star investigations

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Chinese Physics C 2019年第5期43卷 93-98页

作者： Houyuan Chen Dehua Wen Na Zhang School of Physics and Optoelectronics South China University of Technology

Inasmuch as the hydrostatic structure of the interior of neutron stars uniquely depends on the equation of state(EOS), the inverse constraints on EOS from astrophysical observations have been an important method for revealing the properties of high density matter. Currently, most EOS for neutron star matter are given in tabular form,but these numerical tables can have quite different resolution. To guarantee both the accuracy and efficiency in computing the Tolman-Oppenheimer-Volkoff equations, a concise standard for generating EOS tables with suitable resolution is investigated. It is shown that EOS tables with 50 points logarithmic-uniformly distributed in the supra-nuclear density segment [ρ_0, 10_(ρ0)], where ρ_0 is the nuclear saturation density, correspond to the interpolation induced errors of ～0.02% for the gravitational mass M and ～0.2% for the tidal deformability ∧.

关键词： neutron star equation of state tov equations

风电场电缆集电网操作过电压的模拟试验和暂态分析

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高电压技术 2014年第1期40卷 61-66页

作者：刘学忠王贤宗 Li Yishan Abdul Saboor 尚雨辰张天龙西安交通大学电力设备电气绝缘国家重点实验室西安710049 维斯塔斯技术研究中心(新加坡)有限公司新加坡138632

为了解决大型风力发电场中压电缆集电网系统的暂态过电压防护及绝缘配合问题以提高风电场运行的安全可靠性,搭建了风力发电场中压电缆集电网系统的实验室模拟试验平台,并建立了相应的电磁暂态分析模型,研究了真空断路器的操作在风电场... 详细信息

为了解决大型风力发电场中压电缆集电网系统的暂态过电压防护及绝缘配合问题以提高风电场运行的安全可靠性,搭建了风力发电场中压电缆集电网系统的实验室模拟试验平台,并建立了相应的电磁暂态分析模型,研究了真空断路器的操作在风电场中压电缆集电网系统中产生的暂态过电压的特性。采用永磁操作真空断路器的选相位技术来测量最大操作过电压水平,得到了操作过电压水平与电缆长度、感性负载和断路器动作相角的密切关系。模拟试验结果表明,短电缆和大感性负载时开断断路器会产生最高的过电压,真空断路器发生重燃现象时过电压标幺值可达5。模拟200 MW风电场的暂态仿真分析表明,重合闸操作可产生最高2.4的过电压标幺值。

关键词：电缆集电网操作过电压暂态过电压 tov 风力发电场 WPP 真空断路器 VCB 暂态分析

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交流特高压避雷器用监测器动作特性研究

高电压技术 2008年第11期34卷 2295-2299页

作者：王保山陈国强汤霖张志伟熊易张曦左中秋陈立贾锦朝国网电力科学研究院武汉430074 国家电网公司北京100031 郑州祥和集团电气设备有限公司郑州450016

为了判断特高压避雷器的运行工况,针对国家电网公司特高压交流试验基地的情况,在4次1000kV变压器投合的背景下,对6相特高压避雷器用监测器的动作次数和电流进行了分析。分析表明,晋东南—荆门1000kV特高压交流试验示范工程1000kV瓷外套... 详细信息

为了判断特高压避雷器的运行工况,针对国家电网公司特高压交流试验基地的情况,在4次1000kV变压器投合的背景下,对6相特高压避雷器用监测器的动作次数和电流进行了分析。分析表明,晋东南—荆门1000kV特高压交流试验示范工程1000kV瓷外套式金属氧化物避雷器技术协议中提出的监测器的下限动作电流难以正确反应避雷器实际运行工况,为此提出了监测器门槛动作电流的新概念并明确了门槛动作电流的区间范围,按此原理调整监测器将能更准确的动作,更利于特高压避雷器的运行工况判断。

关键词：特高压 MOA 监测器 tov 动作特性门槛动作电流

Mass Limit of Neutron Star

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International Journal of Astronomy and Astrophysics 2014年第2期4卷 414-418页

作者： Jehangir Ahmad Dar Inventor at Department of USIC/EDC University of Kashmir Hazratbal Srinagar India

The mass limit of neutron star has still remained a mystery. The existing Tolman-Oppenheimer-Volkoff (tov) equation for calculating the limit always gives different values, by introducing different assumptions and having been predicted like 0.7 Mo, 3.2 Mo, 3.6 Mo, where Mo = 1.98 × 1030 Kg. There is a need of some better technique to adopt other than tov relation to seek out the value. In this paper, a new relation between the mass of the collapsing star and its average density ρ′ has been derived and used to calculate the limit of neutron star. The conditions in radii between Schwarz Child’s radius and the actual radius of the collapsing star have been introduced to calculate the mass of star above which it will transform into a black hole and below it to a neutron star. A new constant, JN = 8.53707554 × 1039 N-3/2s-3Kg3 has been proposed with which if we introduce the average density of the collapsing neutron star, its mass limit can be calculated very easily. By putting the most possible mass density, which is the minimum required density for a collapsing star to transform into the black hole, it has been found that the mass limit of neutron star is quite higher than it has been assumed. The definition for black hole has also been re-defined on the basis of said radii conditions.

关键词： Black Hole Neutron Star Schwarz Child’s Radius Relation Degeneracy Pressure Event Horizon FCC and HCP Lattices and tov Equation