MotorControl Workbench parameters explanation

[luke514]

Hi everyone, I’m using MotorControl Workbench with X-NUCLEO-IHM08M1 and NUCLEO-G474RE and browsing through the user manual: file:///C:/Program%20Files%20(x86)/STMicroelectronics/MC_SDK_6.4.2/Documentation/html/pages.html

In my project (under the various headings in the left-hand section), there are a few settings that I don’t know how to configure, and I can’t find any explanation for them in the manual.

I will list the parameters in question, grouping them by category.

1) PWM Generation

1a) What is PWM Idle state high side? And low?

Should I set them according to what is written in the L6398? If it uses active high inputs for the upper side (HIN) and active low inputs for the lower side (LIN), I think I should set them that way, right?

1b) How to set Charge boot capacitor duty and Charge boot capacitor time?

I will refer to “AN5789 Considerations on bootstrap circuitry for gate drivers",but I ask you for advice on these two parameters (duty and time)

2) Current Sensing

2a) How to set Reguator execution time? Does it depend on the PWM sensing number? I have three shunts in my three-phase inverter but I only use two of them; I calculate the third current .. should I set it equal to Tpwm?

2b) How to set Trise?

Should it include the MOSFET (STL220N6F7) switching time and the amplifier settling time?

3) Bus Voltage Sensing

3a) How to set Bus Voltage Divider?

If I'm not mistaken, on the X-NUCLEO-IHM08M1 board, the voltage divider for the bus is composed of resistors R17 and R18 à Rratio = R18 / (R17 + R18) = 0.0522. Should I enter the inverse of this value?

4) Temperature Sensing

4a) How to set dV/dT? ..I saw the 10k NTC thermistor placed near the power stage, connected in a divider with a 4.7k pull-up resistor powered at 3.3V, but I wouldn't know how to set that parameter

5) Speed Sensing Config

A clarification regarding this last section...

6) ENCODER QUESTION:

My encoder has a 5V differential output, but the NUCLEO-G474RE operates at 3.3V and accepts single-ended signals .. do I need a voltage shifter to avoid permanent damage to the microcontroller inputs? Se si, avete qualche cosniglio?

(my encoder is SE462000AB10030)

Thank you for your support.

[GMA]

Hello @luke514,

As you are using the X-NUCLEO-IHM08M1 and NUCLEO-G474RE, workbench parameters are set according to the board characteristics.
1. Refer to the PWM generation parameters chapter of the MCSDK User Manual available through Workbench tool > About > Documentations > Documentation.
2. The regulator execution time is defined in the MC Workbench Current Sensing tab and specified in the PWM number. Trise is defined in the power board JSON description file.
3. The VBUS divider is defined in the power board JSON description file and reported in the MC Workbench Bus Voltage Sensing tab.
4. dV/dT is defined in the power board JSON description file and reported in the MC Workbench Temperature Sensing tab.
5. Start-up parameters are used for alignment purposes as described in the quadrature encoder sensor feedback processing chapter of the MCSDK User Manual.
6. Refer to STM32G474 Datasheet for 5 V input Tolerance.

[luke514]

Hi and thank you for your reply!

You’ve clarified a few points for me; I should have specified how to set/choose those parameters when I will use the STM32G474MCT3 with my hardware PCB (which I’m currently developing).

In other words, all those parameters defined in the power board’s JSON (you mean the X-NUCLEO-IHM08M1, right?) which are now automatically set on the Workbench when I select the uC + power board… how will I define them with my hardware?

For example, how will I personally set the regulator execution time for current sensing? ... from a theoretical point of view, once I have my PCB with the STM32G474MCT3, what criteria will I use to choose it?