| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a monitoring device of an AC motor which hardly receives an influence of a current amplitude, and is high in detection accuracy. <P>SOLUTION: The monitoring device monitors abnormalities of a plurality of the AC motors 3 which are connected to a common power supply 1 in parallel, and is constituted of a voltage detection means 6, an individual current detection means 5, a full-current detection means 4, a power operation means 74 which operates individual power and the whole power from outputs of the voltage detection means 6, the individual current detection means 5, and the full-current detection means 4 respectively, an effective value operation means 75 which operates the respective effective values from the outputs of the voltage detection means 6, the individual current detection means 5, and the full-current detection means 4, and a phase difference operation means 77 which operates phase differences of a full current and an individual current from outputs of the power operation means 74 and the effective value operation means 75. When the phase differences exceed an abnormality determination level which is specified by the AC motor 3, it is determined that the AC motor 3 is abnormal. <P>COPYRIGHT: (C)2011,JPO&INPIT |
