High energy storage density capacitors in pulsed power application

This paper studies the main performance parameters and measurements of metallized polypropylene film capacitors， such as energy density， voltage maintaining performance and insulation resistance. Through current and insulation resistance tests are carried out for metallized film capacitor windings， and parameter optimization of the windings is discussed. According to the requirement of high current， long lifetime and vacuum applications， a 50 kV/20 F metallized film capacitor with 120 kA/80s discharge current is developed， which can work at -50 to 60 ℃. After impregnation techniques optimization， the lifetime of the capacitor can be increased up to 2 to 3 times that of the dry metallized film capacitor. An impregnated metallized film capacitor with energy storage density of 2.0 kJ/L is designed and tested with a lifetime over 1 000 shots. It can achieve a lifetime of over 10 000 shots with energy storage density of 1.3 kJ/L. Another capacitor with 1.4 kJ/L energy storage density is designed and tested with discharge current storage up to 100 kA in vacuum applications (pressure lower than 10-3 Pa).