DC backup power supply device and method for diagnosing the same
View Patent ↗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.
1. A DC backup power supply device comprising:
an AC/DC converter for converting an AC power to a DC power;
a DC/DC converter for receiving the DC output power of the AC/DC converter and controlling a voltage of the received DC output power;
a bi-directional DC/DC converter connected to a DC path of a main circuit between said AC/DC converter and said DC/DC converter via first switching means, said main circuit having a load connected to the DC/DC converter; and
DC power storage means connected to the bi-directional DC/DC converter,
said device further comprising:
means for detecting a current and/or voltage within the DC backup power supply device; and
means for monitoring an abnormality in the DC backup power supply device on the basis of an output of the current/voltage detecting means,
wherein a smoothing capacitor is connected to a side of said bi-directional DC/DC converter having the first switching means, and said monitoring means includes means for charging said smoothing capacitor from said DC power storage means through the operation of said bi-directional DC/DC converter, means for turning ON said first switching means after the charging operation, and means for confirming a change in a voltage across said smoothing capacitor before and after the first switching means is turned ON.
2. A DC backup power supply device comprising:
an AC/DC converter for converting an AC power to a DC power;
a DC/DC converter for receiving the DC output power of the AC/DC converter and controlling a voltage of the received DC output power;
a bi-directional DC/DC converter connected to a DC path of a main circuit between said AC/DC converter and said DC/DC converter via first switching means, said main circuit having a load connected to the DC/DC converter; and
DC power storage means connected to the bi-directional DC/DC converter,
said device further comprising:
means for detecting a current and/or voltage within the DC backup power supply device;
means for monitoring an abnormality in the DC backup power supply device on the basis of an output of the current/voltage detecting means;
second switching means connected between said bi-directional DC/DC converter and said DC power storage means;
means for detecting an abnormality in said bi-directional DC/DC converter; and
means for turning OFF said second switching means on the basis of operation of said abnormality detecting means.
3. A DC backup power supply device comprising:
an AC/DC converter for converting an AC power to a DC power;
a DC/DC converter for receiving the DC output power of the AC/DC converter and controlling a voltage of the received DC output power;
a bi-directional DC/DC converter connected to a DC path of a main circuit between said AC/DC converter and said DC/DC converter via first switching means, said main circuit having a load connected to the DC/DC converter; and
DC power storage means connected to the bi-directional DC/DC converter,
said device further comprising:
means for detecting a current and/or voltage within the DC backup power supply device;
means for monitoring an abnormality in the DC backup power supply device on the basis of an output of the current/voltage detecting means;
second switching means connected between said bi-directional DC/DC converter and said DC power storage means; and
means for detecting an abnormality in said second switching means when detecting a current flowing through said DC power storage means under a condition that the second switching means is turned OFF.
4. A DC backup power supply device comprising:
an AC/DC converter for converting an AC power to a DC power;
a DC/DC converter for receiving the DC output power of the AC/DC converter and controlling a voltage of the received DC output power;
a bi-directional DC/DC converter connected to a DC path of a main circuit between said AC/DC converter and said DC/DC converter via first switching means, said main circuit having a load connected to the DC/DC converter; and
DC Power storage means connected to the bi-directional DC/DC converter,
said device further comprising:
means for detecting a current and/or voltage within the DC backup power supply device;
means for monitoring an abnormality in the DC backup power supply device on the basis of an output of the current/voltage detecting means;
means for performing first abnormality diagnosis over a section including said DC power storage means and said bi-directional DC/DC converter within said DC backup power supply device under a condition that said first switching means is turned OFF; and
means for performing second abnormality diagnosis over a section including said DC power storage means and said bi-directional DC/DC converter within said DC backup power supply device under a condition that said first switching means is turned ON.
5. A method for diagnosing a DC backup power supply device comprising:
an AC/DC converter for converting an AC power to a DC power;
a DC/DC converter for receiving the DC output power of the AC/DC converter and controlling a voltage of the received DC output power;
a bi-directional DC/DC converter connected to a DC path of a main circuit between said AC/DC converter and said DC/DC converter via first switching means, said main circuit having a load connected to the DC/DC converter; and
DC power storage means connected to the bi-directional DC/DC converter,
said method including steps of:
performing first abnormality diagnosis over said DC backup power supply device under a condition that said first switching means is turned OFF; and
when an abnormality is not detected in said first abnormality diagnosis step, turning ON said first switching means to perform second abnormality diagnosis over said DC backup power supply device.