针对高压脉冲电容器的稳定性即电容量随贮存时间延长而增大导致产品失效的问题,对其电容量漂移进行了跟踪研究,发现在自然贮存条件下,其电容量的变化存在“保持-激增-再保持”几个特征明显不同的变化阶段。贮存初期,高压脉冲电容器的电容量变化〈0.5×10^-3,贮存中期,电容量激增,贮存后期,电容量逐渐趋于稳定。该结构的理论计算和分析表明:贮存初期电容量的变化主要原因是吸油和溶胀及应力调整等物理变化;贮存中期电容量的激增是由电容器内部的化学反应造成;贮存后期各种反应达到动态平衡状态,电容量缓慢增长。故提出高压脉冲电容器在使用前应进行8-12个月的自然贮存调整,以保证使用时其电容量的稳定性。
In order to obtain the results of the capacitance variability of high voltage pulse capacitors which are stored under normal room condition, the capacitance variability of high voltage pulse capacitors is researched. The experimental results indicate that capacitance varies throughout the storage time obviously. In the beginning of storage, the capacitance is unchangeable in principle, while in the medium storage time, the capacitance increases sharply. Compared to these two different variations, the capacitance of high voltage pulse capacitor increases slowly in the fi- nal storage time. Some conclusions about capacitance variability based on the theoretical computing and hypothesis are drawn. The different capacitance variations of high voltage pulse capacitor boil down to various factors, such as the physical variety, chemical reaction, product of reaction and so on. In the author's view, in the beginning of storage, the capacitance variation results from physical variety, while in the medium storage time, the capacitance variation results from chemical reaction. Accordingly, it is suggested that this kind of high voltage pulse capacitor should be stored for 8-12 months before application.