I am new to the c2000 series, having used the MSP432x series with the driverlib functions.
I would want to generate a 3-phase AC inverter triggering signals in the low 10khz region for an inverter using IGBTs.
This eliminates PWM type triggering and so have to revert to the 6-step output based on the 180 degree conduction mode.
Driverlib examples will be most welcome.
I have attached a word file showing the IGBT switches and the desired switching sequence. Are there any driverlib examples to get me started?
Brief explanation of the switching sequence:
S1 and S3 and S5 are all switched on for half the period .
but S3 waveform is delayed from S1 by 120 degrees
and S5 is delayed from S1 by 240 degrees ( or 120 degrees from S3).
S2, S4 and S6 are the complements of S1, S3 and S5 respectively.
I assume i should be able to generate these waveforms using 3 EPWMx modules with the EPWMxA and EPWMxB outputs as complements and
the deadband of each EPWMx module set appropriately.
Looking at the desired waveforms i assume 2 possible approaches:
a) Set up the EMPWM1x , EPWM2x and EPWM3x modules so that the outputs of EPWM2x and EPWM3x are delayed by the 120 and 240 degrees
with respect to EPWM1 respectively.
Similar to a having 3 free running oscillators but after the 1st is started, the 2nd is started after 120 degrees ( i.e 1/3 the period)
but with the same starting "phase" as the 1st. The 3rd is started after 240 degrees ( i.e 2/3 the period) but with the same starting "phase" as the 1st.
Is this synchronization possible with the EPWMx modules ?
b) From Fig. 2 generate the given waveforms of S1, S3 and S5 ( complements being automatically created by the EPWMx hardware) over each 0-360
degree interval OR maybe 60 degrees -to the next 60 degree interval.
The 60 degree to the next 60 interval was suggested since from my reading on SVPWM, i notice the starting state for the 1st 60 degree sector is 100 (
which is where the 60-120 degrees occurs in Fig 2.
Thanks
David Nyarko
