Part Number: TMS320F28335
Other Parts Discussed in Thread: MOTORWARE
Tool/software: Code Composer Studio
I am debugging over modulation for PMSM.
While I meet some trouble during my debugging; finally, it cannot work as my expectation.
my formula to calculate t1 / t2 is as below separately.
t1 = sqrt(3) * Us * Ts * sin(pi/3 - theda) / Udc;
t2 = sqrt(3) * Us * Ts * sin(theda);
Note : Theda here means the angle in each sector;
My step to debug this functionality is :
1, start the dynamometer machine with 1000 rpm;
2, start the motor under test with 50Nm;
3, increase the speed continuously until Udc is ultilized as much as it can be;
I know each sector with pi/3 will be divided into 3 sub-sector, the 1st & 3rd one will share the same calculation method , and whose trajectory will be a small arc, while the 2nd one will a straight line.
Then finally, the motor will not spin very well, far away from my expectation.
I know the core for over modulation is to get proper t1 & t2, which can guarantee the motor will never be out of control.
I want to know if somebody else meet some similar trouble and how to handle this kind of over modulation.
thanks.
4, then over modulation will be called. while the torque will dropped to 0 soon.
