电工技术学报2025，Vol.40Issue(10)：3326-3338,13.DOI:10.19595/j.cnki.1000-6753.tces.240786
基于磁流体动力学仿真的低压交流串联故障电弧致火风险研究
Research on Fire Risk of Low Voltage AC Series Fault Arc Based on Magnetohydrodynamics Simulation
摘要
Abstract
The low-voltage power supply and distribution system is directly connected to the user at the end of the power system.Its wide distribution,diverse applications,and complex structure make overhauling difficult and lack safety maintenance.Due to its negative resistance characteristics,the series arc can decrease line current,exhibiting high concealment of fault characteristics.It is a loophole in traditional relay protection methods.The series arc fault can produce high temperatures in a short time,which can cause a fire very quickly.The temperature characteristics of AC fault arcs have not been thoroughly studied,the development process and influencing factors of fault arc temperature are not apparent,and the mechanism of arc ignition and disaster needs to be clarified.This paper builds a real experimental platform for arc ignition,constructs a numerical simulation model of AC arc fault based on magnetohydrodynamics,verifies the temperature characteristics of arc fault through simulation and experiment,clarifies the ignition mechanism of arc fault,and puts forward suggestions for the improvement of relevant standards. Firstly,based on the IEC 62606 standard,combined with a temperature acquisition device,an experimental platform for arc fault ignition risk is built to simulate arc faults.The current,voltage,temperature,and thermal imaging images are collected.Secondly,the physical characteristics of AC fault arc and related test standards are analyzed,and a complete set of fault arc simulation schemes is designed.Thirdly,the control equation,calculation domain,and boundary conditions of the arc fault magnetohydrodynamic simulation model are defined,the material parameters are designed,and the division of the simulation grid is refined.Finally,by analyzing the simulation model's calculation results,the fault arc's temperature characteristics are obtained,and experiments verify the simulation results. The simulation results show that the temperature of the AC fault arc increases periodically,and the maximum temperature of the arc appears near the instantaneous peak value of the current.At this time,the influence range of arc temperature also increases significantly.The arc temperature is a cumulative process but develops rapidly in half an AC cycle.The arc current level and arc gap distance are the main factors influencing the maximum temperature of the arc,and the current level plays a decisive role in directly affecting the severity of the arc fire risk.The maximum temperature of the arc increases linearly with the current level below the 32 A current level,and the maximum temperature growth rate slows down after the 32 A current level. The existing arc fault product standards can effectively limit the maximum temperature of arc fault and the influence range of arc temperature.However,even in the time specified in the standard,the arc center temperature can still reach more than one thousand degrees.Therefore,the standard can be improved by limiting the influence range of arc temperature to reduce the fire risk.Low current arc ignition ability cannot be ignored.The current level range covered by the relevant standards should be expanded,and the maximum removal time of 1 A and 2 A current level arc faults is recommended to be 3 s and 1.5 s,respectively.The standard action characteristic requirements should be refined to prevent arc fault hazards and reduce electrical fires comprehensively.关键词
低压故障电弧/串联电弧/磁流体动力学仿真/电气火灾/电弧致火风险Key words
Low voltage fault arc/series arc/magnetohydrodynamics simulation/electrical fire/arc fire risk分类
动力与电气工程引用本文复制引用
盛德杰,王尧,邢云琪,于敬涛,包志舟..基于磁流体动力学仿真的低压交流串联故障电弧致火风险研究[J].电工技术学报,2025,40(10):3326-3338,13.基金项目
国家自然科学基金面上项目(52277143)、中央引导地方科技发展资金项目(科技创新基地项目)(226Z2102G)、河北省高等学校科学技术研究项目(CXY2023006)和浙江省自然科学基金项目(LTGG23E070001)资助. （52277143）
