在轨道交通中,接触式验电器用于接触网停电作业中检测接触网是否停电,以确保作业地线的正确操作和检修工作安全进行。接触电极作为接触式验电器的重要组成部分,直接影响验电信号的采集。为研究接触式验电器的接触电极结构对验电结果的影...在轨道交通中,接触式验电器用于接触网停电作业中检测接触网是否停电,以确保作业地线的正确操作和检修工作安全进行。接触电极作为接触式验电器的重要组成部分,直接影响验电信号的采集。为研究接触式验电器的接触电极结构对验电结果的影响,以GSY-II型27.5 k V交流验电器和ZGD型1 500 V直流验电器为例,分析了其工作原理,并仿真研究了接触电极形状和长度的改变对验电结果的影响。仿真结果表明:对于交流验电器,改变接触电极形状为圆钩型和V型,内部电路的感应信号电压分别变化了3.1%和2.3%,该变化对验电结果影响较小;增加接触电极长度会提高感应信号电压,从而提高验电灵敏度。对于直流验电器,其接触电极形状和长度改变后,内部电路的信号电压保持不变,因此接触电极的形状和长度不影响验电结果。仿真结果为设计和优化验电器结构提供了参考依据。展开更多
The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact ...The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact system.In this paper,an arcing experimental platform that can accurately control the relative speed and distance of electrodes is built,and the influence of different electrode speeds and electrode distances on arc motion characteristics is explored.It is found that there are three different modes of arc root motion:single arc root motion mode,single and double arc roots alternating motion mode,and multiple arc roots motion mode.The physical process and influence mechanism of different arc root motion modes are further studied,and the corresponding relationship between arc root motion modes and electrode speed is revealed.In addition,to further explore the distribution characteristics of arc temperature and its influencing factors,an arc magnetohydrodynamic model under the relative motion of electrodes is established,and the variation law of arc temperature under the effect of different electrode speeds and electrode distances is summarized.Finally,the influence mechanism of electrode speed and electrode distance on arc temperature,arc root distance,and arc root speed is clarified.The research results enrich the research system of arc dynamic characteristics in the field of sliding electrical contact,and provide theoretical support for restraining arc erosion and improving the service life of the sliding electrical contact system.展开更多
To disclose the effect of contact force and electrode gap on the material transfer behavior of Ag-based contact material, arc-erosion tests of the Ag-4wt.%TiB2 contact material were performed for 5000 operations at 24...To disclose the effect of contact force and electrode gap on the material transfer behavior of Ag-based contact material, arc-erosion tests of the Ag-4wt.%TiB2 contact material were performed for 5000 operations at 24 V/16 A under resistive load on an electric contact material testing system. The arc energy and arc duration were investigated, the surface morphologies of eroded anode and cathode were characterized, the mass changes after arc-erosion tests were determined, and the material transfer behavior was discussed as well. The results show that contact force has a significant effect on the arc energy, arc duration and erosion morphology, but has no impact on the material transfer mode. However, electrode gap not only influences the arc energy, arc duration and surface morphology, but also changes the material transfer mode. At 1 mm, the material transfers from anode to cathode. Nevertheless, an opposite mode presents at 4 mm, which is from cathode to anode.展开更多
文摘在轨道交通中,接触式验电器用于接触网停电作业中检测接触网是否停电,以确保作业地线的正确操作和检修工作安全进行。接触电极作为接触式验电器的重要组成部分,直接影响验电信号的采集。为研究接触式验电器的接触电极结构对验电结果的影响,以GSY-II型27.5 k V交流验电器和ZGD型1 500 V直流验电器为例,分析了其工作原理,并仿真研究了接触电极形状和长度的改变对验电结果的影响。仿真结果表明:对于交流验电器,改变接触电极形状为圆钩型和V型,内部电路的感应信号电压分别变化了3.1%和2.3%,该变化对验电结果影响较小;增加接触电极长度会提高感应信号电压,从而提高验电灵敏度。对于直流验电器,其接触电极形状和长度改变后,内部电路的信号电压保持不变,因此接触电极的形状和长度不影响验电结果。仿真结果为设计和优化验电器结构提供了参考依据。
基金supported by National Natural Science Foundation of China(Nos.U19A20105 and 52077182)。
文摘The relative motion of the electrodes is a typical feature of sliding electrical contact systems.The system fault caused by the arc is the key problem that restricts the service life of the sliding electrical contact system.In this paper,an arcing experimental platform that can accurately control the relative speed and distance of electrodes is built,and the influence of different electrode speeds and electrode distances on arc motion characteristics is explored.It is found that there are three different modes of arc root motion:single arc root motion mode,single and double arc roots alternating motion mode,and multiple arc roots motion mode.The physical process and influence mechanism of different arc root motion modes are further studied,and the corresponding relationship between arc root motion modes and electrode speed is revealed.In addition,to further explore the distribution characteristics of arc temperature and its influencing factors,an arc magnetohydrodynamic model under the relative motion of electrodes is established,and the variation law of arc temperature under the effect of different electrode speeds and electrode distances is summarized.Finally,the influence mechanism of electrode speed and electrode distance on arc temperature,arc root distance,and arc root speed is clarified.The research results enrich the research system of arc dynamic characteristics in the field of sliding electrical contact,and provide theoretical support for restraining arc erosion and improving the service life of the sliding electrical contact system.
基金Projects(51274163,51605146) supported by the National Natural Science Foundation of ChinaProject(U1502274) supported by Key Program of the National Natural Science Foundation of China+2 种基金Project(2018M632769) supported by the China Postdoctoral Science FoundationProject(2017SKY-WK010) supported by the Research Fund of Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources,ChinaProject(18JK0722) supported by Special Research Program of Shaanxi Provincial Department of Education,China
文摘To disclose the effect of contact force and electrode gap on the material transfer behavior of Ag-based contact material, arc-erosion tests of the Ag-4wt.%TiB2 contact material were performed for 5000 operations at 24 V/16 A under resistive load on an electric contact material testing system. The arc energy and arc duration were investigated, the surface morphologies of eroded anode and cathode were characterized, the mass changes after arc-erosion tests were determined, and the material transfer behavior was discussed as well. The results show that contact force has a significant effect on the arc energy, arc duration and erosion morphology, but has no impact on the material transfer mode. However, electrode gap not only influences the arc energy, arc duration and surface morphology, but also changes the material transfer mode. At 1 mm, the material transfers from anode to cathode. Nevertheless, an opposite mode presents at 4 mm, which is from cathode to anode.
