In accordance with the increasing frequency fluctuation and complex voltage and current sharing in high-voltage large-capacity energy storage module

a design method of supercapacitor micro source for auxiliary frequency regulation is proposed. The common product combinations are listed by combining the actual super capacitor product data with the voltage and capacity constraints of the energy storage device. The half bridge submodule is adopted to save the device cost because of the weak demand for further increasing output level. The voltage sharing algorithm is added to the carrier stack modulation

and the detailed trigger block diagram of each switching devices is presented. The research results show that the inrush power is less than 0.35%

hysteresis time less than 30 ms

and the difference of the unit value for submodule terminal voltages are limited in 0.07%. During the auxiliary frequency regulation

the ratio of the output energy to the rated energy is about 64.1%. Above research results can provide references for the practical application of supercapacitors.