The Physics behind how motors work. Understanding motors (Link here)
The best series I encountered. Includes Park/Clark transformation and FOC
Physics simulation for Brush-Less Direct Current (BLDC) motor.
Why?
1. To be an interactive tool and support tutorials on BLDC motor opration.
2. To interact with the controller during development (Software In The Loop). This eliminates the needs for any hardware during early stages of controller develop.