Cogging torque

[robin.cornelius@xxxxxxxxxxxxxxxxxxx]

Dear group,

I am trying to calculate the cogging torque for a brushless rotor, 
but I am having some fundimental problems (this is not my area of 
expertiese !).

What intergral should i look at ? . I have tried a line intergral 
around the air gap between stator and rotor (with a reasonable dense 
mesh) and looked at the torque from stress tensor. (I am then steping 
the rotor around to see the value at different pole pitches).But the 
magnitude of the results is too large and the pitch/value graph is 
not quite what i would expect. I remember that David M. mentioned 
coenergy in a past email in relation to cogging torque? if this is 
good to use over what areas should this be evaluated (iron,air,magnet 
all?)

Any advice greatly appreicated.


Robin Cornelius

robin.cornelius@xxxxxxxxxxxxxxxxxxx