Controller and method for transitioning between control angles

A method comprising:

• controlling switching of an inverter that powers a motor based on a first angle in a first mode and a second angle in a second mode;
• determining a difference between the first and second angles;
• storing the difference when a transition from the first mode to the second mode is commanded;
• decreasing a magnitude of the stored difference to zero;
• calculating a sum of the stored difference and the second angle;
• and
• controlling the switching based on the sum in the second mode.

A system comprising:

• a control module that controls a motor based on a first rotor angle in a first mode and that controls the motor based on a second rotor angle in a second mode;
• an angle determination module that (i) determines the second rotor angle based on a sum of a stored value and a third rotor angle and (ii) after the second mode is selected, sets the stored value to a difference between the first rotor angle and the third rotor angle;
• and
• a reducing module that reduces a magnitude of the stored value to zero over a non-zero period after the second mode is selected.