XMC1000 Motor Control - Speed Ref Pot & ADC (DC Current)

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Not applicable
Hi,

enabling the Speed Ref Potentiometer in the DAVE Apps (PMSMFOCSL01/02) adds 3 ADC channels.
This is also documented in the multiple Application Kit Apps Documentations:

"By enabling POT measurement, 3 ADC channels are added automatically:
Channel A - Average current measurement
Channel B - DC link voltage measurement
Channel C - Potentiometer measurement"

What the Pot does is basiclly setting the Endspeed Reference.

In the single-shunt examples with PMSMFOCSL01 this makes sense.
In the 2/3 shunt app PMSMFOCSL02 there is no (average) link current necessary, but checking "Speed Ref via Pot" adds 3 ADCs too!

My question is: Is the DC-link current ADC necessary for the control algorithm in 2/3 shunt Configuration?
In applications with 2/3 shunts, this signal is not available. And I don't see where or if this signal is used in the code.

Best regards
S. Moench
0 Likes
2 Replies
elegantk
Employee
Employee
Hi,

The PMSMFOCSL02 (two/three shunt app) does not required the DC-link current.
Yes... The allocation of the resource is not nice... Sometime, it required some additional resource/IO pin which is not necessary.


1. Default (2 shunt)
Channel A - ADCCH001/0 (Phase-U current measurement)
Channel B - ADCCH001/1 (Phase-V current measurement)

2. When you change from default to 3 Phase current measurement
Channel A - ADCCH001/0 (Phase-U current measurement)
Channel B - ADCCH001/1 (Phase-V current measurement)
Channel C - ADCCH001/2 (Phase-W current measurement)

3. When you change from default to 2 Phase current measurement with "Speed Ref via POT"
Channel A - ADCCH001/0 (Phase-U current measurement)
Channel B - ADCCH001/1 (Phase-V current measurement)
Channel C - ADCCH001/2 (Phase-W current measurement) -> assigned but not used
Channel D - ADCCH001/3 (DC link voltage measurement) -> assigned but not used if "SVM compensated not enabled"
Channel E - ADCCH001/4 (Potentiometer measurement)

4. When you change from default to 3 Phase current measurement with "Speed Ref via POT"
Channel A - ADCCH001/0 (Phase-U current measurement)
Channel B - ADCCH001/1 (Phase-V current measurement)
Channel C - ADCCH001/2 (Phase-W current measurement)
Channel D - ADCCH001/3 (DC link voltage measurement) -> assigned but not used if "SVM compensated not enabled"
Channel E - ADCCH001/4 (Potentiometer measurement)

5. When you change from default to 3 Phase current measurement with "Speed Ref via POT" and "SVM compensated"
Channel A - ADCCH001/0 (Phase-U current measurement)
Channel B - ADCCH001/1 (Phase-V current measurement)
Channel C - ADCCH001/2 (Phase-W current measurement)
Channel D - ADCCH001/3 (DC link voltage measurement)
Channel E - ADCCH001/4 (Potentiometer measurement)
0 Likes
Not applicable
Hi,

thank you for your prompt replay. Your information is a good addition to the documentation and Dave.

S. Moench
0 Likes