| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric hoisting machine reducing a loss of an inverter.SOLUTION: In an electric hoisting machine, an inverter device controlling a hoisting induction motor includes: an inverter for hoisting having a current measuring part for measuring an inverter energization current; and an inverter control part for calculating a slip value of the hoisting induction motor on the basis of a motor rotation speed calculated by means of a pulse generated by an encoder during operation and a rotation speed at which the inverter device instructs the operation, determining a load on the basis of a current value of the inverter energization current measured by the current measuring part and the calculated slip value of the hoisting induction motor, and performing the adjustment to a boost value in conformity with the determined load division. The operation is performed by changing the boost value set to a load division of [heavy load] upon the operation start to a boost value of the [heavy load], [medium load], or [light load] in conformity with the load division of the load determination result in an operation action. |
