| 摘要 |
PROBLEM TO BE SOLVED: To suppress the occurrence of overcurrent by the phase-difference between a system and a load at AC link. SOLUTION: The AC-DC conversion apparatus 1 is operated linking with a system 5 and a load 7 through the medium of an AC switch 6. When load current occurs during the off state of the AC switch 6, the phase-difference between system voltage Es2 and load voltage Es1 is caused by a system interconnection reactor XLs and an AC filter 13. Therefore, the phase-difference between the system voltage Es2 and the load voltage Es1 is detected with a phase detector 25 so that the phase-difference is controlled by a phase control circuit 22 to be reduced to zero. The AC switch 6 is turned on to execute the AC link when the phase-difference is 0. |
