DRV8300: Current Control in DRV8300

Hi Sayali,

Thank you for posting to the Motor Driver's forum!

I will aim to provide a response by the end of next week.

Best,

~Alicia

Hello Alicia,

    Thank you for response. We are monitoring phase current of low side Mosfet when it is on, but for current control we need to monitor phase current right.

we have implemented current sense in our design by taking reference of DRV8300EVM below is snapshot of same. after getting SOA,SOB,SOC value can you guide us how to implement current control mode using DRV8300 and MCU. Or is there any other module or IC which can use this input and give current control operation. If have set current limit value through program e.g 10A even though motor wants to take high current it will not take due to current limit of 10A. 

Regards,

Sayali

Hi Sayali,

Sayali Shinde said:

can you guide us how to implement current control mode using DRV8300 and MCU

To clarify, are you trying to implement FOC?

Best,

~Alicia

Hello Alicia,

         Is it possible to implement without FOC , e.g in DRV8320 we are getting total current from total current we can make current control by software.
again I can frame my question, with DRV8300 how to calculate total current. what ever circuit we are using current from that we are getting loop current not total current.

Regards,

Sayali Shinde

Hi Sayali,

Sayali Shinde said:

Is it possible to implement without FOC , e.g in DRV8320 we are getting total current from total current we can make current control by software.

It is possible, I was just asking to help me understand what kind of control mode you are doing.

Sayali Shinde said:

what ever circuit we are using current from that we are getting loop current not total current.

Can you share a waveforms of the currents measurements that you are getting? 

Best,

~Alicia

Hello Alicia,

  The current control mode we are looking is like if we set some value lets say 8A in program, driver should not provide more than 8A current to motor, if motor is trying take more current it should reduce the speed to maintain power. We just want to put current limit . for this I think we need to calculate total phase current, but with DRV8300 we are getting individual loop current.

     Below is snapshot of current ISEN. 

Blue waveform is ISENA, Red is VSENA, Green is Phase current of A

schematic snapshot is also attached for reference, please let me know if more information or any waveform is needed.

Regards,

Sayali Shinde

Hi Sayali,

Alicia is out of office this week, and will get back in office next week. Please anticipate a delayed response. 

Best Regards, 
Andrew 

Hello Alicia,

   Any update.

Regards,

Sayali 

Hello Alicia,

   Thanks for inputs. Please check below snapshot of waveform which contain Blue- ISENA, Red-VSENA ,Green -Phase A current.

From ISENA waveform can we implement current limit without FOC. If so can you share document which will help us to implement current limit by monitoring ISEN and  without FOC .

Regards,

Sayali

Hello Alicia,

          Thank you for quick revert. whatever waveform we share of ISENA is that correct. Is it possible to you to give some flow or block diagram to implement current limit .what input we need to give microcontroller and how we can validate with waveform that current limit is happening because we cannot wait till end of summer .our whole design is completed only current limit feature is pending

Regards,

Sayali