Guangdong Menlo Electric Power CO.,LTD is a High-tech enterprise integrating research and development, the production, the sale and the post-sale service.
Guangdong Menlo Electric Power CO.,LTD is a High-tech enterprise integrating research and development, the production, the sale and the post-sale service.
Guangdong Menlo Electric Power CO.,LTD is a High-tech enterprise integrating research and development, the production, the sale and the post-sale service.
Guangdong Menlo Electric Power CO.,LTD is a High-tech enterprise integrating research and development, the production, the sale and the post-sale service.
Guangdong Menlo Electric Power CO.,LTD is a High-tech enterprise integrating research and development, the production, the sale and the post-sale service.
薄膜电容器的自愈原理主要涉及两个方面:放电自愈和自动降低电场强度。
放电自愈:
当薄膜电容器中的薄膜介质受到超过其承受能力的电场强度时,会在薄膜内部发生击穿。
如果击穿点是一个金属性瑕疵点,低电压下电容器就已经发生放电自愈。对于半导体或劣质绝缘性瑕疵点,则需出现高压放电自愈。
放电自愈过程中,瑕疵点周围的电流密度急剧上升,产生焦尔热,导致金属化层的熔化,并引发飞弧。电弧很快蒸发和抛散掉该处熔融金属,形成无金属层的绝缘隔离区,电弧熄灭,实现自愈。
自动降低电场强度:
当薄膜电容器介质受到超过其承受能力的电场强度时,介质内部会发生击穿,导致电荷在介质的断点上聚集。
这会产生强电场并在此强电场的作用下产生大量电子和空穴,这些电子和空穴会使介质分解成一些气体或离子,并产生热量。
最终,介质在其周边形成一层较厚的绝缘皮,这层绝缘皮会自动降低电场的强度,从而进一步阻止电流的流动。同时,在介质的表面或周围形成的电荷云也会逐渐减弱电场强度,使电容器的绝缘状态自动恢复。