| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric construction machine that executes automatic idling control by a simple configuration, while reducing the load of control adjustment. <P>SOLUTION: An inverter device 29 reads in a threshold corresponding to a target rotational frequency indicated by a rotational-frequency indicator 28 during normal mode. In a state where a primary current of a permanent-magnet synchronous motor 30 becomes smaller than the threshold, the inverter device determines whether a prescribed period of time elapses to determine whether it is in a low-load state, such that all hydraulic actuators are not operated. When it is determined that the prescribed period of time elapses, in a state where the primary current of the permanent-magnet synchronous motor 30 becomes less than the threshold, it is switched to an idling mode from the normal mode to become a low-idling rotational frequency by controlling an applied voltage of the permanent-magnet synchronous motor 30. <P>COPYRIGHT: (C)2011,JPO&INPIT |
