多断口真空开关多间隙真空电弧协同作用特性与调控机理研究

Vacuum circuit breakers（VCBs）with multi-break overcome the environmental problems such as greenhouse effect, exhaust emission and high liquefaction temperature which are caused by application of SF6 gas high-voltage circuit breaker. It is the development tendency to replace the SF6 circuit breaker and apply in extra-high and ultra-high voltage. The characteristic of series vacuum arc plasma, dynamic voltage distribution and post-arc dynamic dielectric recovery in VCBs with multi-break are the hot issues. However, The synergy characteristics and regulation mechanism of multi-gap series vacuum arcs are still finite and deficient. In this project, the theoretical modeling and experimental study are investigated to research the influence of the arc memory on the current-zero characteristic and ascertain the synergistic reaction mechanism among the current-zero characteristic, the dynamic voltage distribution and the post-arc dynamic dielectric recovery. The influence of the magnetic field regulation on the dynamic voltage distribution, the post-arc dynamic dielectric recovery and the electrode temperature is comprehensively researched to the proper and effective magnetic field regulation in VCBs with multi-break. Based on the synergy characteristics and regulation mechanism of multi-gap series vacuum arcs, the optimized design on single vacuum interrupters which is exclusively used in series multi-break VCBs and the control strategy is explored. The project sweeps the theoretical and technical barriers in the design process of multi-break VCBs, which will improve the level of the electric power equipment in China.

SF6断路器使用中存在温室效应、废气污染和液化等环境问题。多断口真空断路器是有效解决这些问题并在未来替代SF6断路器的解决途径之一。目前对多断口真空断路器动态均压，弧后介质恢复，开断能力等宏观特性研究较多，但针对多断口真空开关串联电弧协同作用特性及调控机理尚缺乏深入、细致的研究，制约了其在电力系统中的应用。本项目通过理论建模与实验研究，获得燃弧阶段电弧记忆效应对零区特性的差异性分布影响规律，揭示零区微观特性、弧后动态电压分布及弧后介质恢复强度之间的协同作用机理。综合磁场对多断口真空断路器动态电压分布、弧后动态绝缘特性及触头熔融等影响规律，得到适用于多断口真空断路器的有效磁场调控方法。基于串联电弧协同作用特性及调控机理，提出串联用单断口真空断路器的优化设计方法及多断口真空断路器的调控策略。本项目旨在为更高电压等级多断口真空断路器的研制与开发扫除理论和技术障碍，提升我国电力装备水平。

多断口真空开关具有无污染、免维护的优点，同时克服了短间隙击穿电压饱和的问题，是一种极具发展前景的电力设备。本课题主要围绕多断口真空开关多间隙真空电弧协同作用特性与调控机理展开研究。首先，从微观粒子运动特性的角度分析了不同燃弧阶段对弧后等离子初始状态的影响，揭示了不同燃弧情况下，电流过零点时断口的弧后离子初始浓度、离子运动速度不同对弧后介质恢复过程和电压分布的影响，并采用PIC鞘层发展模型仿真分析电弧记忆效应对弧后鞘层发展的作用规律。在上述研究的基础上，设计并搭建了多断口真空开关合成回路试验平台，试验研究了在有较小容量均压电容情况下，外加磁场的磁感应强度和施加时间对弧后动态电压分布的调控规律。考虑商用灭弧室优化需求，建立了多断口真空断路器偏磁场分析模型，对多断口真空断路器磁场分布及偏磁场进行计算，提出磁场优化方案。对3种商用灭弧室组合成的多断口真空开关进行分压试验，验证了合理配置不同结构灭弧室自均压方案的可行性。为推进多断口真空开关在550kV及以上电压等级应用，研究了不同燃弧阶段对多断口真空开关弧后动态电压分布特性的影响。通过调整两个断口的开断速度和燃弧时间，对比不同条件下动态电压分布情况，寻求有利于电压均衡分布的开断方式。课题研究成果为多断口真空开关向高压、超高压电力系统中的推广应用奠定坚实的理论与实验基础。基于本课题，获得辽宁省科技奖2项，发表论文25篇，其中SCI/EI论文21篇，授权专利8项，培养研究生15名。