摘要 |
<P>PROBLEM TO BE SOLVED: To provide a control device of an induction motor for making a quick response easily even if a supply voltage of AC power source feeding power to an inverter, which drives the induction motor at variable speeds, drops below a specified fluctuation range or abruptly changes. <P>SOLUTION: A secondary magnetic flux command value Φ<SB>2</SB><SP>*</SP>of an induction motor 3, which is output from a magnetic flux command calculator 14 constituting a control device 7 of the induction motor 3, is limited using a magnetic flux limit value Φ<SB>2lim</SB>derived by a magnetic flux limit calculator 71, based on a detection value V<SB>dc</SB>of output voltage of a rectifier circuit forming a main circuit of the inverter 23, a detection value ω<SB>r</SB>of rotational speed of the induction motor 3, a constant voltage Vm of the induction motor 3, and a constant rotational speed ω<SB>rb</SB>. Even if a voltage of an AC power supply 1 abruptly changes or an operation of the control device 7 is restarted while the induction motor 3 is idling at a high speed, the magnetic flux limit value Φ<SB>2lim</SB>can be quickly derived, so that quick-response control operation is achieved. <P>COPYRIGHT: (C)2010,JPO&INPIT |