Study on Life of High Voltage Ceramic Capacitors under Continuous Charge-Discharge Conditions

In order to improve the service life of pulse power supply devices, this paper investigates the life of high voltage ceramic capacitors based on SrTiO3 under continuous charge-discharge conditions with 10 Ω load and without load. The reason for life reduction of capacitors with the increase of charge voltage was discussed. The charge voltage increase will result i n the increase of electrical stress and temperature of ceramic dielectric under capacitors charge-discharge conditions. This will lead to the development of discharge channel and the leakage current increase. So the life of capacitors was reduced. The reason of capacitor life increase was discussed in detail because of the load in discharge circuit. The load existence in discharge circuit will make the temperature increase slower. This will make the breakdown speed of capacitors slower. In order to make the life of ceramic capacitors increased to 105 times under continuous charge-discharge conditions without load in the discharge circuit, the charge voltage of ceramic capacitors need to be decreased to ~70% rated voltage. In order to make the life of ceramic capacitors increased to 105 times under continuous charge-discharge conditions with 10 Ω load in the discharge circuit, the charge voltage of ceramic capacitors need to be decreased to 80% rated voltage.