Patent ID: 9331521
Filing Date: 2016-05-03
CPC Classification: H02J

Claim Text:
1. An energy storage apparatus, comprising: an input unit configured to receive a DC power from a solar cell; a sensing unit configured to sense and output a voltage level of the solar cell; a signal generating unit configured to generate a periodic signal whose magnitude is periodically changed; a voltage generating unit configured to generate a reference voltage corresponding to the periodic signal; a control signal generating unit configured to generate a duty control signal by using time intervals in which the periodic signal has a magnitude lower than or higher than the reference voltage; a charging unit configured to perform a charging operation by means of an on/off switching operation in response to the duty control signal; a battery unit configured to charge an energy by means of the charging operation of the charging unit; and a main control unit for causing the voltage generating unit to adjust the reference voltage to a lower level when a current solar cell voltage is lower than a previous solar cell voltage and to adjust the reference voltage to a higher level when the current solar cell voltage is higher than the previous solar cell voltage.