| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric power conversion apparatus protection device where reliability of a protection circuit is improved. <P>SOLUTION: Provided is an electric power conversion apparatus protection device that performs overvoltage protection on an electric power conversion apparatus including: a three-level converter 3 whose input is an AC power source and that includes first short-circuit fault detection means; DC capacitors 4P and 4N; and a three-level inverter 6 that includes second short-circuit fault detection means for detecting an internal short-circuit fault. The electric power conversion apparatus protection device includes: a first diode bridge circuit 8 that rectifies an input of the three-level converter; a first thyristor circuit 10 that is provided for a DC output of the first diode bridge circuit 8 and performs thyristor ignition when the first short-circuit fault detection means is actuated; a second diode bridge circuit 9 that rectifies an output of the three-level inverter 6; and a second thyristor circuit 11 that is provided for a DC output of the second diode bridge circuit 9 and performs thyristor ignition when the second short-circuit fault detection means is actuated. The first and second thyristor circuits are each constructed by connecting a plurality of thyristors in series. <P>COPYRIGHT: (C)2012,JPO&INPIT |
