| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve such problem that there is possibility that a zero-phase current might flow from a system 109 via a diode built in a converter 102 while the gate of one converter 101 deblocks and the gate of the other converter 102 blocks, which might cause the malfunction of a ground detecting relay 116 or the erroneous break of a breaker 118, in power conversion equipment 100 which has voltage type PWM converters 101 and 102, which interconnect with AC systems 108 and 109 connected with a common transformer 123 without a transformer and share a DC part, and electromagnetic contactors 106 and 107 which are installed between these AC terminals and the above AC systems. <P>SOLUTION: At start of the power conversion equipment, one PWM converter 101 is started, and when starting residual PWM converter 102 after that, the time until deblocking the gate of the converter after turning on an electromagnetic contactor 107 connected with the converter 102 is set shorter than the working time of the ground detecting relay 116 of the connected AC system 109. <P>COPYRIGHT: (C)2008,JPO&INPIT |
