Abstract: A method and a control device for identifying the angle and polarity of the rotor of a permanent magnet synchronous motor (PMSM), the motor including a stator, including windings and a rotor including at least two permanent magnets. The method includes the steps of determining the rotor d-axis direction by supplying a stator voltage vector pulses to the motor terminals at at least two different stator angles, measuring the phase current at each angle, and determining rotor d-axis position based on motor inductance value in each stator angles calculated from the measured values and determining the rotor d-axis polarity by supplying a current vector to the motor terminals at the q-axis direction, and determining the magnet polarity by observing the direction of the rotor rotation during the test pulses.

Abstract: A method and a control device for identifying the angle and polarity of the rotor of a permanent magnet synchronous motor (PMSM), the motor including a stator, including windings and a rotor including at least two permanent magnets. The method includes the steps of determining the rotor d-axis direction by supplying a stator voltage vector pulses to the motor terminals at at least two different stator angles, measuring the phase current at each angle, and determining rotor d-axis position based on motor inductance value in each stator angles calculated from the measured values and determining the rotor d-axis polarity by supplying a current vector to the motor terminals at the q-axis direction, and determining the magnet polarity by observing the direction of the rotor rotation during the test pulses.

Abstract: A method for controlling a crane includes controlling a rope part connected to a hook of the crane with a friction-operated driving wheel, extra rope being coiled into a plurality of layers onto a storage reel. In the method, two machineries are used, of which the first is intended for the driving wheel and the other for the storage reel, one machinery being controlled with a speed instruction and the other machinery with a torque instruction.