Method and Apparatus for Motor Lock or Stall Detection

摘要

A method and apparatus are provided for detecting a rotor lock condition in a sensorless permanent magnet synchronous motor. A BEMF observer determines an estimated rotor speed {circumflex over (ω)} and a first BEMF voltage value in an estimated rotor-related γ,δ reference frame. In addition, a second estimated BEMF voltage value is calculated in a rotor-related d,q reference frame based on at least a first motor constant and an estimated rotor speed {circumflex over (ω)}. After generating a BEMF error filter value from the first and second estimated BEMF voltage values and calculating a BEMF error threshold value as a function of the estimated rotor speed {circumflex over (ω)} that is subject to a minimum threshold BEMF value, a rotor lock condition is detected based on at least the BEMF error filter value and the BEMF error threshold value.

主权项

1. A method for detecting a rotor lock condition in a sensorless permanent magnet synchronous motor, comprising:
determining a first estimated back electromotive force (BEMF) voltage value in an estimated rotor-related reference frame using a BEMF observer; calculating a second estimated back electromotive force (BEMF) voltage value in a rotor-related reference frame based on at least a first motor constant and an estimated rotor speed {circumflex over (ω)}; generating a BEMF error filter value from the first and second estimated back electromotive force (BEMF) voltage values; generating a BEMF error threshold value as a function of the estimated rotor speed {circumflex over (ω)} subject to a minimum threshold BEMF value; and detecting a rotor lock condition in the sensorless permanent magnet synchronous motor based on at least the BEMF error filter value and the BEMF error threshold value.