| 摘要 |
PROBLEM TO BE SOLVED: To provide a power converter with an abnormality judging function of an AC motor, in which the generation of dielectric breakdown at an armature winding caused by micro surge is surely detected, and abnormality is judged precisely. SOLUTION: A direct current at a given voltage is fed to an induction motor 2 immediately before the induction motor 2 is started by an inverter system 1. At this time, the primary resistance of the induction motor 1 is calculated from a current and a voltage detected by a voltage detector 6 and a current detector 7. When a change (decrease) from an initial value attains a given limiting value, abnormality occurrence is notified from an indicator 11. Then, since abnormality in dielectric resistance due to micro surge can be detected, a secondary disaster such as burning of the motor 2 can be prevented. |
