电解电容器负极引出部位发生跳火的理论研究

研究了在特大纹波电流下电解电容器发生负极跳火的现象。通过对电容器的充放电过程模型进行分析,指出跳火的根本原因在于电容器负极铆接或冷压焊接的引出部位容量很小,会产生反向的电压并逐渐对引出部位进行电压化成,因此产生负极跳火现象。采用负极引出贴箔或增容处理工艺,可有效避免负极跳火,135℃,2000h试验后电容器的失效率为0。

Study on the theory of sparkover at the cathode lead position of the electrolytic capacitor

The phenomenon and principle of the cathode sparkover were studied by the test applied with extra high ripple current. By analyzing the charge and discharge process of the capacitor, the root cause of cathode sparkover is defined to be quite small capacitance at the stitching or pressing point of the negative polarity of the capacitor, which will result in reverse voltage and gradually form the lead position, consequently the cathode sparkover happens. It is indicated that covering the cathode lead position...