基于ANSYS的40.5kV真空灭弧室电场分析

建立了电压等级为40.5 k V真空灭弧室的二维模型,利用有限元软件ANSYS计算并分析了该40.5 k V真空灭弧室在不同主屏蔽罩半径下的电场和电位分布,对比了不同主屏蔽罩半径下触头沿面的电场强度分布以及波纹管屏蔽罩与主屏蔽罩弯角之间的电场分布。结果表明:1主屏蔽罩半径越大,其电场强度越小,当半径大到一定程度时,电场强度不再随主屏蔽罩半径的变化而变化;2当主屏蔽罩半径为57 mm时,该40.5 k V真空灭弧室内部场强分布最为均匀。     

高压真空灭弧室内部电场分布的影响因素

为了解高电压真空灭弧室内部的电场分布情况,建立了真空灭弧室的电场数学模型。应用电场数值分析方法和有限元软件详细计算不同屏蔽罩与触头尺寸对真空灭弧室内部电场分布影响的结果表明,因高电压真空灭弧室开距较大,触头间隙不再是场强集中的区域,在高压真空灭弧室小型化设计过程中,除考虑电极间的绝缘外,更需考虑电极与屏蔽罩之间的绝缘。合理设计屏蔽罩的尺寸、位置和触头的形状可有效改善灭弧室内部的电场分布,提高真空灭弧室的耐压能力,从而为国内72.5kV以上电压等级真空灭弧室的研制提供了理论依据。     

高电压等级真空灭弧室绝缘结构的研究

为了解真空灭弧室的绝缘性能,通过对72.5kV真空灭弧室试品的冲击耐压试验以发现规律、分析其影响因素并改进绝缘结构。试验表明,其内部绝缘击穿并非发生在触头间隙,而是触头背部与主屏蔽罩间的间隙放电。增大触头边缘与背部过渡处的圆弧半径后,提高了耐压水平。进一步提出126kV真空灭弧室内部绝缘结构的设计方案,计算了电场分布情况并用真空灭弧室绝缘击穿的统计特性分析其耐压特性。     

高压真空灭弧室电场的计算分析及结构改进

应用有限元法对外屏蔽罩结构真空灭弧室内部电场分布进行了计算和分析,计算中设电位边界条件不对称,且悬浮屏蔽罩的电位为未知量,并计及电极表面带电粒子的影响,得出了灭弧室中电场分布严重不对称影响灭弧室的耐压和开断性能的结果,进而提出了改善电场分布的措施。     

真空灭弧室设置不同屏蔽罩的均压作用

本文阐述了均压屏蔽罩在高电压真空灭弧室中的应用及其重要性,介绍了各种不同屏蔽罩在高电压真空灭弧室内所起的均压作用,触头开距与屏蔽罩之间的配合以及触头和屏蔽罩形状的分析。     

126kV户外真空断路器灭弧室电场仿真计算

采用有限元软件对126kV户外真空断路器的灭弧室内部电场进行了仿真计算，考虑了灭弧室内部各种屏蔽罩对电场分布的影响，得出了一些有益的结论，为户外真空断路器的设计提供了理论基础。     

10 kV户外真空断路器电场数值分析

采用有限元法对10kV户外真空断路器灭弧室内部电场进行计算分析,得出不同外绝缘情况下的电场分布情况。通过对真空灭弧室在不同外绝缘尺寸、厚度等条件下悬浮电位的计算及灭弧室内部电场进行的一系列仿真分析,为户外真空断路器的设计及外绝缘设计提供了理论基础。     

SF6罐式高压断路器三维电场计算与分析

基于开发的三维有限元仿真软件计算了 SF6 罐式高压断路器灭弧室内的三维电场 ,得到灭弧室内的电场强度分布 ,发现喷口对灭弧室中电场分布的影响较大 ,它的存在使触头附近电场及其变化增大 ,触头间电场更不均匀     

影响 35kV 真空灭弧室电性能的因素分析

通过试验与理论分析，研究了灭弧室内部电场分布、触头结构、触头材料及制造工艺等因素对３５ｋＶ真空灭弧室电性能的影响，提出了解决我国３５ｋＶ真空灭弧室存在弧后重燃和耐压水平下降问题的思路     

真空灭弧室的几种主屏蔽罩电场仿真分析

<正>介绍了在电力系统一个重要元件——真空灭弧室的主屏蔽罩结构设计。随着真空灭弧室产品向小型化和低成本发展,主屏蔽罩的结构也发生相应变化。真空灭弧室作为真空断路器的核心元件,其质量性能好坏直接决定了真空断路器的使用性能表现。市场上,真空灭弧室典型结构组成如图1所示。主屏蔽罩作为真空灭弧室的关键零件之一,主要作用是当触头之间产生电弧时有大量金属蒸气和液滴向真空灭弧室四周喷溅,这些电弧生成     

Electric field optimization design of a vacuum interrupter based on the Tabu search algorithm

During interruption in the vacuum interrupter, the re-ignition between the contact and the shield is influenced by the shape of the contact and size of the shield. The design of the contact and the shield is an intricate optimization problem. In this paper, the Tabu search algorithm is applied to optimize the contacts of a 35 kV vacuum interrupter. The optimization design is based on electric field computation using the finite element method. By solving the inverse problem, the optimization of the contacts is achieved, and a reasonable distribution of the electric field is obtained. Based on the combinatorial optimization Tabu search algorithm, an improved universal algorithm for continuous variables global optimization is proposed.     

A utility optimization method of a high voltage vacuum interrupter design

In this paper, a new method of electric field design of high voltage vacuum interrupters is proposed. According to the multi-gap insulation effect and the vulnerable breakdown spots theory, the symmetrical voltage shields are proved to be effective. So the initial model of a high voltage vacuum interrupter is designed. Next with finite element methods and optimization theory, a mathematical model of electric field intensity in interrupters is given. What's more, by optimizing this model with finite element software, a more symmetrical electric field in vacuum interrupters is obtained and its peak value appear as in the second auxiliary gaps (the two gaps between the center floating shield and the symmetrical voltage shields). The result shows that with this method, the vacuum interrupters can withstand higher static breakdown.     

Compact high-voltage vacuum circuit breaker, a feasibility study

This study focuses on a compact vacuum circuit breaker (CB) for nominal voltage of 72.5 kV, nominal current of 2000 A and short circuit current of 31.5 kA. The dielectric conception of the vacuum interrupter (VI) is based on a multiple floating shield configuration which reduces the risk of total breakdown due to partial breakdown between the contacts and shield. An optimised electrical field distribution on the contact surface with the maximum field pointing towards the floating shield is arranged and hence reducing the breakdown effective area of the contacts facing each. All tests have been performed on a specially designed single-phase circuit breaker pole-unit equipped with a low energy spring type mechanism. Interruption performance was confirmed in direct tests. The circuit-breaker pole was proved to be restrike-free with respect to cable charging class C2. Dielectric tests in new condition and after interruption tests confirmed the announced ratings. These tests confirm the feasibility of this HV-CB with 25% more compact VTs based on the outlined dielectric conception.     

Critical Radius of Axial Magnetic-Field Contacts in Vacuum Interrupters

Vacuum circuit breakers (VCBs) are widely used to protect medium-voltage (MV) power distribution circuits. Since SF$_{6}$ gas is specified as a global warming gas, VCBs are stepping into a higher voltage sector to protect power transmission circuits. Axial magnetic field (AMF) contacts are widely used in vacuum interrupters. In this paper, we propose a concept of critical radius of AMF contacts. When coil width and coil height are fixed, the axial magnetic flux density increases first with increasing contact diameter. Then, it reaches a maximum value. Thereafter, the axial magnetic flux density decreases. The contact radius corresponding to the maximum axial magnetic flux density is critical radius. The concept of critical radius is validated by coil-type AMF contacts and slot-type AMF contacts in MV vacuum interrupters with finite-element analysis. Critical radius is only related to contact geometry parameters and the current has no influence on critical radius. Critical radius increases with increasing contact gap, coil width, coil height, and thickness of the contact plate. In high-voltage AMF vacuum interrupters, axial magnetic flux density per kiloampere increases with increasing contact diameter since the critical radius is typically high with a high contact gap and it is in the rising branch. In an MV AMF vacuum interrupter, interrupting capacity could increase with an increase of the contact diameter with a different rising rate before and after the critical radius. This is expected to be experimentally validated.      

基于面积效应的真空灭弧室触头间隙击穿特性研究

针对一种中压真空灭弧室模型,研究开距变化时触头有效面积对击穿电场强度的影响。通过电场仿真计算得到了开距对触头间隙内有效面积的影响;通过冲击耐压试验得到了开距与击穿电场强度之间的关系。在此基础上发现在不同的开距范围内,触头间隙内的有效面积对击穿电场强度的影响不同:在开距1～2 mm范围内击穿电场强度Ebd随着触头有效面积Se的增大而增加;在开距2～6 mm范围内击穿电场强度Ebd随着触头有效面积Se的增大而减小。     

改善真空灭弧室纵向磁场分布的研究

本文对真空灭弧室触头纵磁场进行了研究,并提出了一种触头结构,以期增强纵磁场效应。由于这种改进结构,使触头的烧蚀减少,并已被实验证明。本文也给出了相应的数学模型和计算机程序。     

40.5kV真空断路器灭弧室内的暂态电场计算

计算了40.5kV真空断路器开断空载变压器时由复燃和截流引起的暂态过电压.通过离散的傅里叶变换获得暂态过电压的三个主要频率分量,以此作为真空断路器的边界条件,首次对真空断路器灭弧室内的暂态电场采用有限元方法进行了计算.给出了灭弧室内的暂态电场分布,电场强度的最大值、发生时间及典型位置的电场强度随时间变化的曲线.讨论了暂态电场的一些特征,为真空断路器的绝缘设计提供参考.