controllable speed crane driver motor and crane driver rotation speed control method

摘要

A method according to the invention of controlling a rotation speed of a motor of a speed-controllable hoist drive comprises receiving a lift speed instruction; forming a final speed instruction by using initial information containing the lift speed instruction; and using the final speed instruction as a speed instruction for the rotation speed of the motor of the speed-controllable hoist drive. The method further comprises monitoring a position derivative of an actual value of a cable force. The initial information for forming the final speed instruction comprises the position derivative of the actual value of the cable force.