Power supply device having hierarchical structure

Abstract

Provided is a power supply device for supplying power to load elements. The power supply device includes a main power module including a main battery, a main power controller configured to control charging and discharging of the main power module, a sub-power module including sub-batteries respectively corresponding to the load elements, and a sub-power controller configured to control charging and discharging of the sub-power module, Based on a remaining capacity of the main battery and a remaining capacity of the sub-batteries, the power supply device is selectively operated in a first mode in which charging and discharging are possible for both the main power module and the sub-power module, a second mode in which charging and discharging are possible only for the sub-power module, or a third mode in which charging and discharging are possible only for the main power module.

Dependencies are inferred from the claim text.