PURPOSE: To increase a charging current for a storage battery within the range of a current for a charger so as to correspond to a fluctuation in a current which is supplied to a load by an uninterruptible power-supply apparatus.
CONSTITUTION: On the basis of a command from a charging-current control circuit, a charger 3 is controlled in such a way that the sum of a current detected by an inverter-current detector 21 and a current detected by a storage- battery-current detector 12 does not exceed a rated current for the charger 3. Alternatively, a value obtained by subtracting, by using a subtracter 32., the-current detected by the inverter-current detector 21 from the rated current, for the charger 3, which is set by a chargercurrent setter 31 is used as a charging-current command value, and a deviation operation device 13 operates a deviation between a charging-current detection value detected by the storage- battery-current detector 12 and the charging-current command value. A current controller 14 to which the deviation is input gives to the charger 3 a control signal which reduces the input deviation to zero, and a large charging current can be given to a storage battery 5 within the range of the rated current for the charger 3.
FUJIKURA MASANOBU
YAMAMOTO SHUNICHI
