Back to results
US 6,650,081 B2Granted
Synchronous motor driving system
AssigneeHitachi, Ltd.
InventorsYoshitaka Iwaji, Tsunehiro Endo, Kiyoshi Sakamoto, Yuhachi Takakura
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeHitachi, Ltd.
InventorsYoshitaka Iwaji, Tsunehiro Endo, Kiyoshi Sakamoto, Yuhachi Takakura
Estimating the term…
Axial error calculation unit is provided for estimating an axial error Δθ between a d-q axis and a dc-qc axis by using Ld, Lq, Ke, Id*, Iq*, Idc and Iqc in a range of all rotational speeds except zero of a rotational speed command of a synchronous motor, Ld denoting an inductance on a magnetic pole axis d of the synchronous motor, Lq an inductance on a q axis orthogonal to the magnetic pole axis d, Ke a generated power constant of the motor, Id* a current command of the d axis, Iq* a current command on a q axis, Idc a detected current value on an assumed dc axis on control, and Iqc a detected current value on an assumed qc axis orthogonal to the assumed dc axis. Irrespective of presence of saliency, position sensorless control can be achieved in a wide range a low to high speed zone.
A synchronous motor driving system which comprises a synchronous motor, an inverter for driving the synchronous motor, a rotational speed command generator for supplying a rotational speed command to the synchronous motor, and a control unit for calculating a voltage applied to the synchronous motor,
A synchronous motor driving system which comprises a synchronous motor, an inverter for driving the synchronous motor, a rotational speed command generator for supplying a rotational speed command to the synchronous motor, and a control unit for calculating a voltage applied to the synchronous motor, said synchronous motor driving system comprising:
Dependencies are inferred from the claim text.