topic S12ZVM FOC - How ADC works ? in Model-Based Design Toolbox (MBDT)

S12ZVM FOC - How ADC works ?

Daniel_Popa — Thu, 22 Nov 2018 09:25:51 GMT

Hi, Daniel,
The example model: S12ZVM FOC Sensorless Motor Control is with one current shunt or two current shunt?
In the ADC0_Command_List model and the ADC1Command_List, the Input Channels are all 16. I am confused.
I am expecting your reply!

Amos.

Re: S12ZVM FOC - How ADC works ?

Daniel_Popa — Thu, 22 Nov 2018 09:43:58 GMT

Hi amosxue‌,

The FOC model for ZVM is using a dual shunt current measurement method.

Inside the FastLoopInput subsystem, there are 2 currents IA, IB that are read from ADC0 and ADC1 respectively.

From the board schematic, we are reading the I_PHASEA and I_PHASEB

These 2 shunt drop voltages are routed to AMP0 and AMP1 pins

That are feed via PAD0 and PAD5 into the microprocessor

These input pins corresponds to ADC0 -> AN0_0 and ADC1 -> AN1_0 channels:

According with ADC Select table, AN0_0 and AN1_0 corresponds to value 16.

This is why you see ADC input channel 16 for both ADC lists.

Both ADC0/1 are read in the same time.

Hope this clarify your concerns.

Best regards,

Daniel

Re: S12ZVM FOC - How ADC works ?

amosxue — Thu, 22 Nov 2018 10:09:11 GMT

Yes, it woks! Thank you for your reply in detail~~~:)

Re: S12ZVM FOC - How ADC works ?

amosxue — Thu, 22 Nov 2018 10:18:39 GMT

The internal AMP1 is disable, I think Phase B current is sampled by External Amplifier (Phase B).