| 摘要 |
Procedure for exact aligning with the storey floor level of a lift cage driven by an alternating current motor, wherein the current in one or several phases of the lift's drive motor (2) is choked with a controllable choke element (22). The control is governed by a control unit (23) which receives information of the lift cage's (8) true velocity, constituting a feedback-connected control loop which imparts to the lift cage in fine adjustment running a low velocity from which the lift cage is able to stop at the storey floor level within a required tolerance range. |
