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

摘要

An apparatus comprises a processing system (201) configured to produce voltage control signals for controlling an electrical machine (202) 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.

主权项

1. A method for controlling an electrical machine comprising two multiphase stator windings, the method comprising:
controlling power stages connected to the multiphase stator windings on the basis of four 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 two multiphase stator windings and mutual inductances between the two multiphase stator windings, converting stator phase currents of the two multiphase stator windings into the four rotation-converted stator currents with a conversion rule corresponding to a form of the model of the electrical machine where each of stator flux-linkages of the model is dependent on only one of the rotation-converted stator currents when inductance parameters of the model are unaltered, and obtaining a position angle of the rotor and using the obtained position angle of the rotor in the conversion of the stator phase currents of the two multiphase stator windings into the four rotation-converted stator currents,wherein inductance coefficients between the stator flux-linkages of the model and the rotation-converted stator currents are proportional to: Ld+Md, Lq+Mq, Ld−Md, and Lq−Mq, where Ld is a direct-axis inductance, Md is a direct-axis mutual inductance between the two multiphase stator windings, Lq is a quadrature-axis inductance, and Mg is a quadrature-axis mutual inductance between the two multiphase stator windings.