BMS & MBDT - RDDRONE-BMS772 MC33772B / S32K144 SPI COMMUNICATION FAULTS

OGUZ1 — Thu, 03 Feb 2022 11:55:55 GMT

Hi,

We try to communicate between MCU(S32K144 - 48Package) and MC33772B on board RDDRONE-BMS772 by using matlab simulink.

First of all, we changed the oscillator on the board with an 8 MHz oscillator, since we couldn't select the Matlab Simulink "XTAL clock" value of 32 MHz.

Then we fed our board with a 6S battery pack (20.41Volt). Since we wanted to measure 6 cells, we made the pin connections. Then, we set the mosfets, we got 20.41 volts from the output of the card.

We connected a 24 Volt 0.15A fan to the output of the card. There are differences between the values we get and the values we see in FreeMaster.

The cell voltage values we measured;
Cell_[0] : 3.391V
Cell_[1] : 3.405V
Cell_[2] : 3.406V
Cell_[3] : 3.407V
Cell_[4] : 3.406V
Cell_[5] : 3.399V

The Isense CURRENT value we measured; 120mA

Question 1) Why are the values of Cell Voltage lower than the real value in FreeMaster?? Especially ISENSE_CURRENT??

Question 2) How do I fix these fault values? (HardwareFault values) ??

Question 3) When we send 0 value from Matlab simulink to the gate of the mosfet, we still measured 20.41 volts at the output. After some time (about 30 minutes), the output voltage dropped to 0. Why doesn't it drop to 0 instantly?

Oguz

Regards

@mariuslucianand

topic BMS & MBDT - RDDRONE-BMS772 MC33772B / S32K144 SPI COMMUNICATION FAULTS in Model-Based Design Toolbox (MBDT)

BMS & MBDT - RDDRONE-BMS772 MC33772B / S32K144 SPI COMMUNICATION FAULTS