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Tool/software:
In continuation with the below discussion.
I want to turn off the PWM once their own period is finished. I am currently using UP-COUNT mode. I am using EPWM4 and EPWM5 for PSFB Converter.
EPWM4A is turned on at TBCTR = 0 by using AQCTLA.ZRO register and turned off using CMPA = 0.5*TBPRD. A dead band module is used in which EPWM4A is used as a source for RED and FED and EPWM4B is generated. A shadow mode is used for CMPCTL and Dead band (RED and FED) (DBCTL) and loading is done at TBCTR=TBPRD.
EPWM5A is turned ON using CMPA (whose value depends on the phase shift required (i.e given by PI controller)) and turned off using CMPB and CMPB value is such that the EPWM5A pulse is 50%. A dead band module is used in which EPWM5A is used as a source for RED and FED and EPWM5B is generated. A shadow mode is used for CMPCTL and Dead band (RED and FED) (DBCTL) and loading is done at TBCTR=TBPRD.
I want to turn off the PWM when a certain condition is reached (i.e Vdc>=410). Additionally, I want the PWM to turn OFF once their own period is finished. I am achieving this by making the dead band greater than the period (TBPRD). SHADOW mode is used for RED and FED, and loading is done at TBPRD.
I am getting the expected results, as shown below. The below figure is for a phase shift between EPWM4A and EPWM5A of 45 degrees.
and I want to turn on the PWM when a certain condition is reached (i.e Vdc<=390). when I turn it back on, below are the results
I have a question though. Is using DB (dead band) values greater than period (TBRPD) okay? or does it have any unexpected operations or instability in PWM's?. I am not seeing any for now. But I just wanted to confirm if using DB greater than TBPRD can cause any problems?
Thank you
