| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide power conversion equipment which returns to its usual operation state stably and quickly after power recovery by suppressing the decrease of the DC voltage during its power stoppage period. <P>SOLUTION: The power converter is composed of: a power converter 10 which receives AC power 1 and drives an AC motor 5; a controller 6 which controls the inverter part 4 of the power converter; a voltage detecting means 7 which detects the voltage of the AC power; a current detecting means 8 which detects the input current of the AC motor; and a speed detecting means 5 which detects the speed of the AC motor. The controller 6 has a vector control means which converts the current detected by the current detecting means 8 into a torque current component and an exciting current component and controls them each independently. When the quantity of electricity obtained from the voltage detected with the voltage detecting means 7 becomes a first specified value or under, it reduces the command of the torque current component, according to the dropped quantity of electricity, and when the above quantity of electricity becomes a second specified value smaller than the first specified value, it zeros the command of the above torque current components. <P>COPYRIGHT: (C)2007,JPO&INPIT |
