| 摘要 |
The present invention is an uninterruptible power supply system (100) provided with multiple uninterruptible power supply devices (10, 20, 30) which are connected in parallel with regard to the load and switch the power sources for supplying power to the load depending on the state of the power sources, a control unit (3) for controlling the power source switching operations of the uninterruptible power supply devices (10, 20, 30), and a storage battery (5) commonly connected to the uninterrupted power supply devices (10, 20, 30). Each uninterrupted power supply device (10, 20, 30) has a converter (15, 25, 35) for converting the alternating-current power of an alternating-current power source to a direct-current power, a connector (41, 42, 43) for switching between the direct-current power converted by means of the converter (15, 25, 35) and the direct-current power inputted from the storage battery (5), and an inverter (17, 27, 37) for converting the direct-current power back to an alternating-current power and for supplying power to a load. The control unit (3) stops the inverter (17, 27, 37) from among the plurality of inverters (17, 27, 37) that does not contribute to supplying the electric energy needed by the load. |
