Hitachi, Ltd.

Hitachi Computer Peripherals Co., Ltd.

Hitachi Maxell, Limited

Hitachi Maxwell, Ltd.

Toshikatsu Miyata

Akihiko Kanouda

Masato Isogai

Fumikazu Takahashi

Minehiro Nemoto

Yoshihide Takahashi

Masahiro Hamaogi

Takao Gotou

Takashi Tanabe

A DC backup power supply system having a battery a charge-discharge circuit for charging and discharging a power between the battery and a DC line and a control circuit for controlling the charge-discharge circuit, wherein the battery has a number of battery cells and cylindrical portions of the battery cells are laid on an approximately horizontal plane.

DC backup power supply system

A reliable uninterruptible DC power supply device. The DC backup power supply device includes an AC/DC converter, a DC/DC converter, voltage step-up/down choppers and a battery connected to a DC path of a main circuit connected with a load via a switch, and a microcomputer. In the device, under control of the microcomputer, the voltage step-up/down choppers are first operated under a condition that the MOS FET was turned OFF for self diagnosis of the backup power supply device. Next, the switch is turned ON to execute the remaining self diagnosis. The DC backup power supply device can execute its self diagnosis with a reduced likelihood of danger of exerting an adverse effect on the main circuit and also can exhibit a reliable uninterruptible power supply function.

DC backup power supply device and method for diagnosing the same

Growing community of inventors

Suita, Japan

Toshikatsu Miyata