What factors are related to the service life of electrolytic capacitors? According to the long-term practical experience, it is concluded that the service life of capacitor is directly related to the temperature of working environment.
The common electrolytic capacitor has been damaged when the ambient temperature is 90 ℃. But now there are many kinds of electrolytic capacitors with high working environment temperature. When the ambient temperature is 90 ℃, the ratio of AC current passing through the electrolytic capacitor to rated pulse current is 0.5, the service life is still 10000h. However, if the temperature rises to 95 ℃, the electrolytic capacitor will be damaged.
When selecting capacitors, the specific environmental temperature and other parameters should be selected. If the influence of environmental temperature on capacitor life is ignored, the reliability and stability of power supply will be greatly reduced, and even the equipment and instruments will be damaged. Generally speaking, the electrolytic capacitor can reach the life requirement of 10000 h when the ambient temperature is 80 ℃.
The higher the temperature, the shorter the life of the capacitor. Therefore, in the selection of electrolytic capacitor model, we must pay attention to the working temperature it can bear, and the appropriate working temperature, and work under the appropriate temperature, in order to better extend the use time of electrolytic capacitor.
The service life of electrolytic capacitor is also related to the AC current and rated pulse current of capacitor working for a long time, which generally refers to the test value under the ambient temperature of 85 ℃. However, some electrolytic capacitors with high temperature resistance are related to the ratio of test data at 125 ℃. Generally speaking, the higher the ratio, the shorter the life of electrolytic capacitor. When the current flowing through the electrolytic capacitor is 3.8 times of the rated current, the electrolytic capacitor is generally damaged. Therefore, the electrolytic capacitor has its safe working area. For general applications, when the ratio of AC current to rated pulse current is less than 3.0 times, the requirements for service life have been met.
It can be seen that the service life of electrolytic capacitor mainly depends on the working temperature and AC current and rated pulse current. After these two working factors are determined, the appropriate electrolytic capacitor can effectively promote the follow-up work.