Energy storage capacitors are a kind of electronic devices which can admit charges at large capacity. In pulse operation, energy storage capacitors can provide ultra-large current as energy storage devices. In electronic systems, pulse current can be filtered into smoother DC current based on the characteristics of charge and discharge of energy storage capacitors, which can reduce the demand on power supply greatly. The application principles and examples in GF-3 satellite of energy storage capacitors in low voltage pulse system are discussed. Through the modeling and simulation of the satellite power supply system, the optimal capacitor parameters are obtained. The design method in this paper can provide a reference to other designs on electronic systems.