| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a driving device for a permanent magnet type motor that can improve both efficiencies at low-speed operation and high-speed operation, that is low-cost, and that has a high reliability to temperature rise. <P>SOLUTION: A driving device for a permanent magnet type motor is driven at variable speed using an inverter, and uses a permanent magnet in a rotor. The driving device for the permanent magnet type motor has, in an inverter control device; an induction voltage constant detector that detects an induction voltage constant; a permanent magnet temperature detector that detects a temperature of the permanent magnet based on the induction voltage constant; an overcurrent cutoff level selector that selects an overcurrent cutoff level based on the temperature of the permanent magnet obtained by the permanent magnet temperature detector; and an overcurrent determining part that determines a current abnormality based on the overcurrent cutoff level selected by the overcurrent cutoff level selector. The overcurrent determining part outputs an abnormal signal when the current abnormality occurs to stop an operation of the inverter. <P>COPYRIGHT: (C)2012,JPO&INPIT |
