In this video, I go over how the field weakening technique works and a common misconception about it.

0:00 Intro
0:28 Why is field weakening needed?
1:38 How field weakening works
5:18 Field weakening misconception
7:00: Field weakening limit? Positive Id?
9:33: Field weakening motor design

References:
Most images come from a great thesis on the topic by Wen Liang Soong:
"Design and Modelling of AxiallyLaminated Interior Permanent Magnet Motor Drives for FieldWeakening Applications"

Python script:
https://github.com/MatanPazi/VFD/blob...

Brushed DC motor diagram:
https://ctms.engin.umich.edu/CTMS/ind...