加压乙二醇/水混合液耐μs级高电压击穿实验研究

Investigation of high voltage electrical breakdown of pressurized glycol/water mixture with microsecond charging

采用同轴电极实验装置,在μs级充电时进行了加压乙二醇/水混合液正电极击穿实验,并对实验结果进行了分析和解释,得出结论如下:击穿场强随静压以1/8次幂的关系而增加;击穿场强系数随乙二醇浓度的增加而增加;加压和添加乙二醇对于提高水介质耐高电压击穿的能力具有可叠加性,加压比添加乙二醇更有效;在静压12×105Pa下乙二醇浓度80%的混合液击穿场强比常压下纯水击穿场强高112.2%。加压提高乙二醇/水混合液击穿场强的主要机制是加压增加了击穿延迟时间。

By means of coaxial apparatus, a high electrical voltage breakdown experiment for pressurized glycol/water mixture with microsecond charging is carried out. The experimental results are presented and analyzed. The conclusions are shown as follows： the breakdown strength increases with the hydrostatic pressure to the one eighth power; the coefficient in Martin formula increases with increasing glycol concentration; the highest breakdown stress of 235.5 kV/cm observed in the glycol/water mixture of glycol concentration of 80% at a hydrostatic pressure of 12 × 10^5 Pa is 112.2% higher than that in pure water at constant pressure; it is accumulative for the pressurization and glycol addition for the capability to improve electrical breakdown strength of water dielectric, and the pressurization is more effective. The primary mechanism of raising breakdown voltage for pressurized glycol/water mixture is that the time lag to breakdown is increased and the formation of bubbles is inhibited.