UNINTERRUPTIBLE POWER SUPPLY APPARATUS

An uninterruptible power supply apparatus includes an operation unit for setting a second reference voltage, a computation unit that calculates a first reference voltage higher than the set second reference voltage and lower than a maximum value of the first reference voltage, a first reference voltage generation unit that generates the first reference voltage calculated by the computation unit, and a second reference voltage generation unit that generates the second reference voltage set by the operation unit. Thus, a voltage of a DC line can be made lower than the maximum value of the first reference voltage for improved efficiency of the uninterruptible power supply apparatus.