Lao He is very busy today. What are you busy? Busy to answer everyone's doubts about high-voltage ceramic capacitors! Someone asked: I want 35KV high-voltage ceramic capacitors, the size is so big, can't fit it! Why is it so big? Can be smaller ?
35KV2000PF high-voltage ceramic capacitors, if the conventional design, the size is not large. The so-called conventional, refers to DC products. In general, DC high-voltage ceramic capacitors of the same capacity and voltage will be much larger than the size of AC high-voltage ceramic capacitors. Explain:
额定工作电压 | 标称容量 | 测试电压 | 雷击电压 | 直径 | 高度 |
35KV AC | 2000PF +-5% | 75 KVAC | 大于 185 KV | 80 +-1MM | 120+-1 MM |
40KV DC | 2000PF +-10% | 75 KVDC | 大于110 KV | 60+-1 MM | 34+-1 MM |
It is not difficult to see from the above table that the two capacitors are AC, one DC, and all are good ceramic media, but the difference can be seen in the appearance, the performance difference is even greater! 35KVAC of this high voltage capacitor, with 75KVAC The test is completely ok for two minutes. If the 40KV is tested with KVAC, it may break down after 50KVAC!
Not only the voltage, partial discharge is not the same. 35KVAC this high-voltage capacitor, placed in the 50KVAC test station is zero. The partial discharge of 40KV high-voltage ceramic capacitor is qualified within 15KVAC, the partial discharge is less than 5PC.
Of course, the difference is not limited to these. For example, the temperature change rate of these two high-voltage ceramic capacitors is 35KV. In the range of -40 degrees to +85 degrees, the capacity change is about 1%, and the capacity change of 40KV is about 15%. %.
So, don't complain that the 35KVAC high-voltage capacitor is too large in size. The performance is different, designed according to the power standard!