| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain a backup function in power failure with high reliability over a long period, in an uninterruptible power supply device which in steady operation supplies electric power to a load solely from a commercial AC power supply, while in power failure supplies power from a secondary battery. SOLUTION: The secondary battery is provided with charging modes: a charging mode A, which is regularly conducted at every period set for a week or longer; and a charging mode B, which is conducted at any time whenever the battery capacity is reduced. In the charging mode A, a charge control system which surely attains the full-charge state is employed, while in the charging mode B, a charge control system which prevents deterioration of the secondary battery by suspending charge before full charge is employed.</p> |
