2019-04-24 08:36 AM
Dear
I want to get 3-phase current, but due to 3 phase current belong to ADC injected channel
After checking the "RCM_ExecRegularConv" function, i find that it will call LL_ADC_REG_StartConversion to do adc conversion. I'm wonder whether i can use the RCM flow to do injected channel conversion
thanks
2019-05-12 02:41 AM
Dear Frank,
You did not give any details regarding your configuration, so I do not know how many ADCs do you have.
Basically, regular_conversion_manager is dedicated to regular conversion only.
This software component, allow the user to add there own regular conversions, and share ADCs that are already used by Motor control current sensing.
Injected conversion is what is done inside the ***_pwm_curr_fdk.c component (*** here represents the topology (3Shunts /1Shunt and if we use 1 or 2 ADCs R3_1/R3_2)
Basically, we sample only 2 currents among the 3 and we compute the third one. Current sampling must be down at a very accurate time and it is why we configure a timer channel to fire the conversion.
Adding a third conversion would imply a major rewrite of the ***_pwm_curr_fdbk.c and it is not an easy task.
So to answer your question, no, regular_conversion_manager is definitely not the place to add a current phase conversion.
Do not hesitate to share your configuration, if for instance you have 3 ADCs with each of them able to access to your shunt resistor, the task could be a bit easier.
Regards
Cedric
2019-05-16 06:25 PM
Dear Cedric
Thanks for your reply.
Currently i use the Nucleo-F303RE + X-Nucleo-IHM08M1-3sh to develop concept demo project, in this architecture i only can use the adc channel which is used by ST motor control library to retrieve phase current value. Due to i want to develop 6-steps control algorithm + current loop control method, so i try to find how to retrieve current in the current setting. Do you have any suggestion about whether i can use these inject adc channel to retrieve phase current
thanks