Method and apparatus for automatically identifying electrical parameters in a sensor-less pmsm
AssigneeRockwell Automation Technologies, Inc.
InventorsJingbo Liu, Mark M. Harbaugh, Thomas A. Nondahl, Peter B. Schmidt, Semyon Royak
Life of this patent
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Abstract
A method and apparatus for determining electrical parameters for commissioning a sensor-less permanent magnet synchronous machine uses knowledge of the rotor position to apply balanced pulses along the rotor magnet axis and perpendicular to the rotor magnet axis allowing measurement of q- and d-inductance at multiple current levels without substantial rotor movement.
Claims23
A motor drive system comprising:
- an electronic computer providing and monitoring electrical signals communicated between the motor drive and stator of a sensor-less PMSM, the sensor-less PMSM having a permanent magnet rotor having a magnet direction and rotatable within the stator,
- a commissioning program executing on the electronic computer to:
- (a) deduce rotor orientation by the application of electrical signals to the stator;
- (b) employ the deduced orientation to apply at least one electrical signal to the stator along a q-axis of the rotor to determine q-axis self-inductance as a function of q-axis current and applying at least one electrical signal to the stator along a d-axis of the rotor to determine d-axis self-inductance;
- and
- (c) operate the sensor-less PMSM using a control algorithm providing electrical signals to the stator and receiving as inputs the q-axis and d-axis inductance, the control algorithm selecting q-axis self-inductance corresponding to an operating q-axis current.
A method of commissioning a sensor-less PMSM having a permanent magnet rotor having a magnet direction and rotatable within stator coils, the automatic commissioning method comprising the steps of:
- (a) deducing rotor orientation by the application of electrical signals to the stator;
- (b) employing the deduced orientation to apply at least one electrical signal to the stator along a q-axis of the rotor to determine q-axis self-inductance as a function of q-axis current and applying at least one electrical signal to the stator along a d-axis of the rotor to determine d-axis self-inductance;
- and
- (c) operating the sensor-less PMSM using a control algorithm providing electrical signals to the stator and receiving as inputs the q-axis and d-axis inductance, the control algorithm selecting q-axis self-inductance corresponding to an operating q-axis current.
In a motor drive system having an electronic computer providing and monitoring electrical signals communicated between the motor drive and stator of a sensor-less PMSM, the sensor-less PMSM having a permanent magnet rotor having a magnet direction and rotatable within the stator, a commissioning program executing on the electronic computer to:
- (a) deduce rotor orientation by the application of electrical signals to the stator;
- (b) employ the deduced orientation to apply to the stator along a q-axis of the rotor to determine q-axis self-inductance as a function of q-axis current and applying at least one electrical signal to the stator along a d-axis of the rotor to determine d-axis self-inductance;
- and
- (c) operate the sensor-less PMSM using a control algorithm providing electrical signals to the stator and receiving as inputs the q-axis and d-axis inductance, the control algorithm selecting q-axis self-inductance corresponding to a operating q-axis current.
Dependencies are inferred from the claim text.