| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the overcharge of a storage battery in a rescue operation at power failure in an elevator driving device using a matrix converter. <P>SOLUTION: An elevator operation direction at power failure is determined by estimating a charge or discharge status of a storage battery for driving. Also as another means, there is provided means for detecting the voltage of the storage battery which is used to reverse the operation direction of a car when the detected value exceeds a predetermined value. In a rescue operation at power failure, there is no fear that the storage battery is overcharged by regenerative energy, which enabling the continued operation as an elevator system at power failure. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
