Effect of creeping distance on High Voltage Capacitor

Example: a high-voltage ceramic capacitor bare sheet, after the bipolar treatment in a vacuum environment, high voltage ceramic chip height is 5MM. So the distance between the two poles is 5MM. What is the safe working voltage? Through experiments, it is found that there is no problem with the vacuum itself and that there should be no discharge phenomenon in the insulation strength of the vacuum. Because there are no air molecules, but when the electricity is turned on to 3KV, the discharge will begin to appear abnormal when it approaches 5KV.

Why is this problem? Is the vacuum not good enough to have gas? Or the quality of high-voltage ceramic capacitors? Perhaps this will be the focus of controversy. The reason is simple: vacuum is fine, high voltage capacitors are fine. The thickness of the 5MM is already greater than the voltage intensity of the 10KV, so why do sparks still occur?

This is the problem of creeping distance. Capacitance and vacuum are all right, but at high voltage around 5KV, the two poles of the high-voltage capacitor discharge because of the short distance. The distance of high voltage capacitor is not related to the quality of the product itself, so the design should be adjusted. Or technical processing to make a protection between the two poles, so that the distance between the poles increased. If you want to boost to about 6KV, it is recommended that the capacitor height or distance between the poles should not be less than 8MM.