Hello all,
As I have started to implement the SVM using etpu api provided by NXP which requires alpha beta inputs. I have calcultaed alpha & beta by the following manner.
alpha = a - b*cos60-c*cos60
Beta = b*cos30 - c*cos30
:where a,b & c are sine angle of of three phases
fs_etpu_pwmmac_update_svm(PWM_master_channel, (Voltage.xalpha * 4194304), (Voltage.xbeta * 4194304));
when I input this alpha beta to etpu api, I get the sector in reverse order(the reference vector rotates in clockwise but it should rotate the anitclockwise as sector 1 to 6 lies in anticlockwise manner), I have also attached image of alpha & beta waveform which I have observed.
When I reverse the alpha beta as
fs_etpu_pwmmac_update_svm(PWM_master_channel, (Voltage.xbeta * 4194304), (Voltage.xalpha * 4194304));
I get the correct sector wise waveform(from sector 1 to 6). So I dont know why this is happening. So please suggest a solution.
Hi, I was searching over old ticket database, it seems AN2969 Figure 2 is incorrect. Unfortunately there is currently no available eTPU expert who could help with that.
I am attaching excel sheet I understand it is correct. Inside that spreadsheet is also a plot of the angle vs sector and our eTPU experts stated it is correct.
Not sure if this helps, at least trying