Abb Schweiz Ag

The Switch Drive Systems Oy

Samuli Kallio

Antti Piippo

Riku Pöllänen

Matti Eskola

Mikko Vertanen

Pasi Peltoniemi

Jussi Karttunen

Tomi Knuutila

Erno Pentzin

A method for stabilizing a DC link voltage of an electrical converter, the method including: determining a DC link voltage signal for the DC link voltage of the electrical converter; determining a fluctuation signal of the DC link voltage by applying a high pass filter to the DC link voltage signal; determining a torque offset by multiplying the fluctuation signal with a gain value; and modifying a reference torque with the torque offset for controlling the electrical converter. The gain value is adjusted by: determining a DC link voltage ripple from the DC link voltage signal; and comparing the DC link voltage ripple with a threshold and, when the DC link voltage ripple is higher than the threshold, increasing the gain value.

Stabilizing DC link voltage with adaptive gain

The present disclosure describes a two-stage method for estimating an angle offset of an angle sensor in a system comprising a permanent-magnet synchronous motor. An initial value for the estimated angle offset is first determined with a short circuit test. Next, a torque of the motor may be controlled so that the motor is maintained at a zero speed. Minor adjustments are made to the value of the angle offset to find a minimum magnitude of stator current. A value at which the stator current is at its minimum is used as a final angle offset.

Method and apparatus for estimating an angle offset of an angle sensor

An apparatus comprises a processing system () configured to produce voltage control signals for controlling an electrical machine () comprising two or more multiphase stator windings. The processing system is configured to produce the voltage control signals on the basis of rotation-converted stator currents expressed in a coordinate system bound to a rotor of the electrical machine and on the basis of a model of the electrical machine modeling at least inductances of the multiphase stator windings and mutual inductances between the multiphase stator windings. The processing system is configured to convert phase currents of the multiphase stator windings into the rotation-converted stator currents with a conversion rule corresponding to a form of the model of the electrical machine where each of the stator flux-linkages of the model is dependent on only one of the rotation-converted stator currents in spite of the mutual inductances between the multiphase stator windings.

Method and an apparatus for controlling an electrical machine with two or more multiphase stator windings

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Helsinki, Finland

Samuli Kallio