Variable speed FOC motor drive

The user guide of Simpower systems has a demo file of variable speed FOC motor drive. Reference : Building Your Own Drive : Systems with electric drives.

On referring to the model implemented, the formulas used for 'iqs* calculation' and 'Teta calculation' use phir for calculation purpose. The function block shows that a value of 1e-3 mWb is added to Phir value. The value has not been indicated in the formulas expressed below. I need to know, why that value of 1mWb has been added to Phir value in calculation.

Answer 1

[Joel Van Sickel]

This is a simple trick to avoid divide by 0.

This answer is part of a MATLAB Answers cleanup effort for unanswered questions that are outstanding.