面向超导电力设备的液氮开断电弧特性研究

Superconducting power technology is the frontier and hotspot of domestic and foreign research. It is the key direction of development of China's "Thirteenth Five-Year Plan" and the United States "Grid 2030". Superconducting power equipment is widely used. The superconducting power devices such as cables, current limiters and transformers have been put into operation. The high-temperature superconducting power equipment adopts liquid nitrogen (LN2) as the cooling and insulating medium. Applicant’s preliminary research results shows that the LN2 medium has a strong ability to break the arc. LN2 has excellent insulation characteristics. The future superconducting power equipment directly uses LN2 breaking current, which makes the equipment environment friendly, compact in structure, and low in on-state losses. LN2 switching is expected to become a promising switching technology. The objective of this project is to obtain the characteristics of LN2 switching arc for superconducting power equipment. Research contents include studying the generation, development, extinction process of LN2 arc; measuring parameters of current zero area of LN2 arc; analyzing the influence of contact materials, contact structures, contact gaps, magnetic fields, applied pressures and other factors on LN2 switching capacity; exploring the dielectric recovery characteristics of LN2 arcs; establishing an LN2 arc model to reveal the influence of key factors on the characteristics of LN2 switching arc. The results of the project are expected to provide basis for the establishment of LN2 arc theory, design of LN2 switches and promote the research and development of the superconducting power technology.

超导电力技术是国内外研究的前沿和热点，是我国“十三五”计划和美国“Grid 2030”计划的重点发展研究方向。超导电力设备应用广泛，电缆、限流器、变压器等超导电力设备已投入运行。高温超导电力设备采用液氮作为冷却、绝缘介质，申请人初步研究结果表明，液氮介质具有较强的开断电弧能力。未来的超导电力设备，直接采用具有优异绝缘特性的液氮开断电流，使设备具有环境友好、结构紧凑、通态损耗低等特点，有望成为一种有前景的开关技术。本项目旨在获得面向超导电力设备的液氮开断电弧特性，研究液氮电弧的产生、发展、熄灭过程及演变规律；测量液氮电弧零区参数；分析触头材料、触头结构、触头间隙、磁场、气压等因素对液氮开断能力的影响规律；探索液氮弧后介质恢复特性，建立液氮电弧模型，揭示关键因素对液氮开断电弧特性的影响规律。项目研究成果可为建立液氮电弧理论提供支撑，为液氮开关的设计提供理论依据，促进超导电力技术的发展。