Vacon Oyj

Vacon Oy

Tero Halkosaari

Jarno Hoffren

Jukka-Pekka Makinen

Pekka Haapamäki

Jukka-Pekka Mäkinen

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.

PMSM rotor angle identification

A method and a system for controlling parallel-connected frequency converters or inverter units feeding an alternating-current motor (MOTOR) provided with parallel windings or separate parallel motors having their shafts mechanically coupled together via a load, in which method the current supplied to the motor is measured. The frequency converters/inverter units are connected to each other via a data bus, e.g. a fast serial bus, and one of the frequency converters/inverter units (FCONor INU) functions as a master device in such manner that it sends to the other device/devices (FCONor INU) information over the data bus regarding the instantaneous value of the current (I) fed by it to the motor, said other devices functioning as follower devices so that they adjust their own current (I) on the basis of the current of the master device.

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Lempäälä, Finland

Tero Halkosaari