STEVAL-CTM009V1 three ICS for activate Motor Profiler

[Takumi Lee]

Hello,
first of all, I would like to thank STMicroelectronics for their commitment to providing information and expertise to the public free of charge. Currently, I am working with a very competent study colleague to set up a test bench.

We intend to operate a PMSM with the mentioned 5KW inverter. It seemed like a simple project at first...

The motor identification was performed using an IHM08M1 setup. The electric machine spun wonderfully! :)
Now we have set up a complete test bench with the mentioned board, the ICS current sensing board, and a Nucleo-F446RE.

After generating QC and settings to make the machine spin, we cannot get the electric machine to run!

After several hours, to be precise, we tried somehow to get the Motor Profiler running.

Ultimately, we saw in the MC Workbench that this function is only possible when the current from all three phases is measured.

The STEVAL-CTM008V1 "Current sensing board" was, of course, expanded for the third ICS, but in the board manager (JSON file), this third current measurement is not implemented. Thus, the Motor Profiler function is disabled!

Now to the actual question.

What do we need to do to inform the board manager/MC Workbench that we can perform three-phase current measurement to activate the Motor Profiler?

Thank you in advance for reading this post; we are very convinced by STMicroelectronics and would prefer not to switch to a competing product. We hope to find a solution to this problem promptly.

[Gael A · Accepted solution]

Hello Takumi Lee,

Could you tell me where have you seen the information that the MotorProfiler only works with 3 phases current sensing ? Because this is not true for STO FOC : we sample only 2 phases and reconstruct the third one thanks to Kirchhoff's first law. Sometimes we can't sample always the same 2 so we need a shunt on each phase, but we don't sample them all at the same time. This is not needed for ICS configurations as ICS can sample the same phases every time, which means that thanks to Kirchhoff's first law we can always reconstruct the third one : ICS can work quite well with only two. What you said is true for HSO, which needs 3-phases sampling for precision purpose.

In any case, the reasons why you can't profile your motor this way are the following : only the STO FOC (meaning not HSO FOC) is available for the STEVAL-CTM009 board, and this board works with 2 or 3 ICS. Unfortunately, 3ICS configuration is not yet supported by the MCSDK for the CTM009 power board. STO FOC can either work on shunts (3Sh or 1Sh) or 2ICS, but not 3ICS. This has to be manually implemented for the STEVAL-CTM009. So simply running your motor using 3-ICS will need a bit of code implementation. (although 2ICS should work well)
Moreover, the Profiler tool does not support ICS at all (neither three nor two). This has been added to our roadmap and should be available in a further release.

If you want to profile your motor, I strongly advise you to use the IHM08 you were mentioning in your post as it is fully supported by the Profiler.

I can help you make your motor run provided you stay on 2-ICS and not 3.

[Takumi Lee]

Hi Gael A,

thank you for the quick response. Yes, in the MCSDK, see the image attached.

Regarding Kirchhoff's law, nodal rule, that is correct! Could you briefly provide the designation for HSO and STO? Unfortunately, we couldn't find the setting/activation of the three shunts on the STEVAL-CTM009V1. We thought we might need to use the ICS! However, using the three ICs would be pretty cool for validation to ensure the shunts are functioning correctly. Possibly, latest on our own board :o ...

In the distant future, concerning our project, we will have to implement current measurement with just the three shunts. Since redundancy will also be a factor, we will measure all three phases. To ensure temporary reliability.

We no longer use the board IHM08M1 for our test bench because we intend to drive a 12KW (15peak) Surface Mount PMSM machine.

Best regards

[Gael A]

Hello Takumi Lee,

What is said in the picture you sent is that the Profiler is only available on 3 SHUNT current sensing. The CTM009 is an ICS board, not shunt, this is why Profiler is not available.

Concerning the HSO (High Sensitivity Observer), it is a flux observer for FOC that allows the user to reach a wider range of speeds (especially low speeds) and provides a strong and quick start-up. By comparison to the STO (ST Observer), who is our default observer which relies on Open Loop start-up (weaker and longer). You can find more information on st.com or in the MCSDK documentation (in the MC WorkBench -> About -> Documentations -> Documentation).

The STEVAL-CTM009 board is not supported on any shunt configuration by the MCSDK, so you will have to do that on your own. Same thing for 3ICS, but 2ICS should be working fine. Take a look at the board's schematic to see if three shunt is even possible with this board.

You can still use the IHM08 for Profiling though you won't be able to reach your motor's max power. However this is fine as only the speed and max current evaluations will be impacted by that and those can be manually modified afterwards in the motor .json file.