I have calculated this constant W for few motors with different stator lengths. Thank you to all friends for giving me some measurements on their motors.
There is long measurement behind each line in this table, that you can see as Excel table and diagrams.
This table with motors of different stator lengths of 12, 20, 24 mm, but the same diameter of 35mm proves that there is a single constant number that specifies the whole family of motors, independent of
- stator length L
- windings number N
- wire size.
you can calculate W-constant for ant stator length
W = 200,000 / L
then with how many windings does my motor need? the complete motor.
You have stator sheets with diameter of 34.5 mm and you wish to build motor. At your power you wish 20 mm stator length. The W constant is then:
then with how many windings does my motor need? you design the whole motor.