摘要 |
<P>PROBLEM TO BE SOLVED: To provide a bidirectional power conversion device with a reverse power flow prevention function, capable of suppressing time lag at switching of reverse power flow prevention operation and voltage transition fluctuation to an AC power distribution network, and capable of reducing energy loss. <P>SOLUTION: A reverse power flow prevention output control circuit 13, if a commercial output current detected by a commercial output current detection circuit 14 underruns a reverse power flow set current value Ism (A), lowers an AC output voltage by controlling switching pattern of a converter 27 of a bidirectional power conversion unit 11 so that the commercial output current does not underrun Ism (A). Thus, power conversion amount from a DC power distribution network 18 to an AC power distribution network 19 is reduced, to prevent reverse power flow. An excessive power in the DC power distribution network 18 is stored in a DC voltage stabilizing battery 12 connected to the DC power distribution network 18, being parallel to the bidirectional conversion unit 11. <P>COPYRIGHT: (C)2007,JPO&INPIT |