| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit for detecting an output missing phase for detecting the missing phase, if a missing phase occurs at any one of a plurality of load devices connected to a three-phase AC power source output from an inverter device. <P>SOLUTION: The circuit for detecting an output missing phase comprises an absolute value arithmetic circuit 13 for obtaining, as an absolute value datum for each phase, the detecting signal of the inverter output current between phases during operation of a plurality of load devices 8a to 8c connected to the inverter device, difference arithmetic circuits 15a to 15c for obtaining each difference Huv, Hvw, Hwu between absolute value data for each phase obtained by the absolute value arithmetic circuit 13, and a judging circuit 16 for comparing the difference between phases obtained by the difference arithmetic circuit 15 with the preset reference difference value to judge that the missing phase occurs when any one of the differences is larger than the reference difference value. <P>COPYRIGHT: (C)2007,JPO&INPIT |
