Electric motor control system with current sensor offset correction
An electric-motor-control system with current sensor offset correction includes three current-sensors and a controller. Each of the three current-sensors is used to detect current through one of three windings of a Y-connected motor. The controller is in communication with the three current-sensors. The controller records periodically measurements of sensed-current indicated by each current-sensor while variable-current flows through each of the three windings, determines an x-offset and a y-offset of a rotating-vector indicated by a plurality of the measurements, and determines an offset-current of each of the three current-sensors based on the x-offset and the y-offset.
1. An electric-motor-control system with current sensor offset correction, said system comprising:
three current-sensors, wherein each of the three current-sensors is configured to detect current through one of three windings of a Y-connected motor; and
a controller in communication with the three current-sensors, wherein the controller is configured to:
record periodically measurements of sensed-current indicated by each current-sensor while variable-current flows through each of the three windings;
determine an x-offset and a y-offset of a rotating-vector indicated by a plurality of the measurements; and
determine an offset-current of each of the three current-sensors based on the x-offset and the y-offset.
2. The system in accordance with claim 1 , wherein the controller is further configured to:
determine a leakage-current based on the plurality of the measurements; and
determine the offset-current of each of the three current-sensors based on the x-offset, the y-offset, and the leakage-current.