| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power unit capable of being used for a parking lot system and can supply electric power even in a power failure.SOLUTION: An electric power unit includes: a first and a second electric power sources to which an electric power is input from a commercial power source; a battery electric power source; and an inverter. The first electric power source supplies an electric power to the inverter. The second electric power source supplies an electric power to the battery electric power source which in turn supplies the electric power to the inverter. The inverter supplies the electric power to a device connected to an output part thereof. Although the electric powers from a first electric power source and the battery electric power source are input into the inverter in parallel, the voltage of the electric power from the first electric power source is set higher than that from the battery electric power source, and the inverter uses the electric power from the first electric power source if the commercial electric power source is not out of service. If the commercial electric power source becomes out of service which causes the voltage of the first electric power source to drop, the inverter uses the electric power from the battery electric power source. |
