Battery system

Abstract

Provided is a battery system including: a solar panel that generates power using solar light; a power conditioning system (PCS) for solar light that converts a direct-current power which is output from the solar panel into an alternating-current power and supplies the converted power to a power system; a secondary battery; a PCS for the secondary battery that converts direct-current power charged and discharged from the secondary battery into alternating-current power and charges and discharges the converted power to and from the power system; and a smoothing unit that calculates a target value with respect to a composite value of power which is supplied to the power system by the solar panel and the secondary battery and gives a charge and discharge command to the PCS for the secondary battery in accordance with the target value. The smoothing unit includes a sample number calculation unit, a moving average calculation unit, and data of an amount of solar radiation, a moving average of an amount of power generation of the solar panel is calculated using a predetermined number of samples in the sample number calculation unit, and the number of samples is increased and decreased corresponding to an increase or decrease in the data of an amount of solar radiation.