六氟化硫断路器灭弧室压力测量导管结构研究

Research on the Tube Structure for Pressure Measurement in SF_6 Circuit Breakers

六氟化硫断路器灭弧室内的暂态压力测量对于优化灭弧室结构设计、提高开断能力有着重要意义。在强电流开断条件下,灭弧室内的恶劣环境给暂态压力测量带来困难。通常需要用导管将待测压力引出至压力传感器以实现高温隔离,导管对测量结果的影响不可忽略。文中首次针对灭弧室暂态压力测量用的导管测压结构展开特性研究,基于Bergh-Tijdeman公式研究了几种抑制共振的典型导管结构,确认了导管内塞填料或多孔导管是较为方便可行的方法。搭建了激波管装置测试导管结构的动态性能,尝试在导管中填塞毛细管来模拟多孔结构,试验结果与理论分析相符,已能满足多数测点的测量要求。

The dynamic pressure measurement in the SF_6 circuit breaker can provide important help to its structural design, and can improve the breaking capability. The harsh environment inside the nozzle during high current interrupting presents difficulties to the pressure measurement. Tubes, which will cause non-neglected influence on the measurement, are usually needed to insulate the pressure probes from high temperature. This paper conducted the characteristic research of the tube structure and studied several typical structures for resonance suppression based on the Bergh-Tijdeman equation. Tubes with fillings or porous tubes were deemed as the convenient and feasible solutions. The shock tube facility was established to test the dynamic performance of different tube structures. Major tubes filled with capillary tubes to simulate the porous structure were tested, and the results are in consistent with the theoretical analysis, which can satisfy the measuring requirements of most points.