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TMDSHVMTRPFCKIT: Per Unit Normalization and ADC conversion in HVPM_Sensorless_2833x

Part Number: TMDSHVMTRPFCKIT

Hi,

Is there any reference or training facility explaining the per unit normalization and how macros work in HVPM_Sensorless_2833x? I am getting very confused especially with ADC conversion. For example, in the code, we have the following for phase A current:

         clarke1.As=((AdcMirror.ADCRESULT1)*0.00024414-offsetA)*2*0.909; // Phase A curr.

ADC result is multiplied to 1/(2^12) and offset is subtracted from it which I do understand! However, I don't get it why it is multiplied by 2 and 0.909. What has happened to the gain of 8.25 of the current sensing amplification system? The voltage that is sensed (Ifb-V in this case) should be equal to:

(ADCRESULT*3.0/4096)+ADCLO

based on the page 10 of SPRU812A. Then, based on the schematic and the amplifying circuit of the high voltage kit, this voltage is equal to :

1.65-(current/(8.25*0.02))

From this, I cannot reach to what is used in the codes. I would appreciate any help especially if there is any comprehensive explanation on how per unit normalization works.

Thanks,