Abstract
In this paper, the charge-and-discharge control method which improves the efficiency of the electric power storage equipment using capacitors is proposed by decreasing the variation in inter-terminal voltages of capacitors resulting from the variation in capacitance. That is, the circuit block is constituted with a pair of capacitors, and two or more switches which switch the capacitors in series or in parallel, and the electric power storage part is constituted by connecting the circuit block to n stage series. And in order to always maintain the output voltage of electric power storage part in the allowable input voltage of an electric power converter, connection of the capacitors in each circuit block is switched in series or in parallel. Furthermore, without using parallel monitor, in the case of charge, by parallelizing preferentially the capacitors in the circuit block with high block voltage, for every short predetermined interval time and in the case of discharge, by serializing preferentially the capacitors in the circuit block with high block voltage, for every short predetermined interval time, the variation in inter-terminal voltages of capacitors is controlled, and the charge-and-discharge efficiency of electric power storage equipment is raised.
