Controller and method for minimizing phase advance current

A method comprising:

• generating a d-axis current (Idr) demand based on a direct current (DC) bus voltage, a rotational speed, and a demanded torque;
• generating a voltage request based on the Idr demand;
• generating an out-of-volts (OOV) signal based on a comparison of the voltage request and an available voltage;
• controlling a motor based on the voltage request;
• selectively applying a first adjustment to the Idr demand;
• identifying whether an improvement resulted from the first adjustment, wherein the improvement is identified based on at least one of (i) a measured current of the motor and (ii) the OOV signal;
• and
• selectively applying a second adjustment to the Idr demand based on whether the improvement is identified.

A method of controlling a motor, the method comprising:

• determining a base demand from a lookup table based on a direct current (DC) bus voltage, a commanded speed, and a demanded torque;
• generating a d-axis current (Idr) demand by adding an adjust value to the base demand;
• generating a voltage request based on the Idr demand;
• setting an out-of-volts (OOV) flag to a first value when the voltage request is greater than an upper limit, wherein the upper limit is based on the DC bus voltage;
• setting the OOV flag to a second value when the voltage request is less than the upper limit;
• generating an OOV signal by averaging the OOV flag;
• controlling a motor based on the voltage request;
• selectively applying a first adjustment to the adjust value;
• identifying whether an improvement resulted from the first adjustment, wherein the improvement is identified when at least one of:
• both of the following are true:
• (i) the OOV signal before the first adjustment is greater than a predetermined limit and (ii) the OOV signal after the first adjustment is less than the OOV signal before the first adjustment;
• or
• all of the following are true:
• (i) the OOV signal before the first adjustment is less than the predetermined limit, (ii) the OOV signal after the first adjustment is less than predetermined limit, and (iii) a measured current after the first adjustment is less than the measured current before the first adjustment;
• when the improvement is identified, applying a second adjustment to the adjust value in a same direction as the first adjustment;
• when the improvement is not identified, applying the second adjustment to the adjust value in an opposite direction of the first adjustment;
• and
• when reset conditions are present, resetting the adjust value to zero, storing the commanded speed, and storing the DC bus voltage,
• wherein the reset conditions include at least one of:
• the OOV signal is greater than a first predetermined value,
• a magnitude of a difference between the commanded speed and the stored value of the commanded speed is greater than a second predetermined value, and
• a magnitude of a difference between the DC bus voltage and the stored value of the DC bus voltage is greater than a third predetermined value.