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Rev-Up phases and meaning


What is the meaning of the five different rev-up (start-up) phases that one can set up in sensorless mode?

From my experiments, I figured that Phase 1 is alignment and Phase 2 is an actual startup phase. Is this correct? What are the other phases for? Where is this described?


Secondly, I'd like to debug the startup procedure as we're having some issues there.
For this I'd like to graph the phases inside the Motor Pilot.
Which Parameter do I have to add for this?

Associate III

I'm no expert but my understanding is that the other phases allow you to achieve a finer grained start up.  You might want an 'S' shaped increase for speed and a rapid increase of current at the start then reducing or increasing more slowly to make sure the motor does not stall.  I don't believe it is mandatory for the first phase to be an alignment phase but that is common practice from what I gather after watching ALL the training videos!.  Then you just have to keep double thinking what that SPEED_UNIT is going to give you.  Sorry I can't give you a more authoritative answer.  I believe it's also OK to set the last however many phases to zero and they will be ignored if you don't want to use them all and your application works without more but I stand to be corrected on that.

Thanks for your input on this.

I worked with a different motor controller before (TI) and the documentation as well as the tools were quite a bit clearer on this...
For example, there was this useful segment in their tool where you could click of the respective phases of the motor running process and you got all the settings related to it.


As for the alignment, there has to be some configuration somewhere where I can change its parameters (type, eg. Alignment, IPD, forced rotation; current and duration).
I couldn't find any considerable information or settings about this; the User Manual only has a screenshot of the tool's respective page in it. The descriptions in the tool are quite useless without more information.

Only through experimentation I found what I already wrote in my first post, however the correctness of this information has yet to be approved from any official side.

Associate III

As for official documentation, the only information I've ever found is in the tutorial videos where in the course of a fairly long video it is discussed briefly.  The advice amounts to something like 'Set the current to half nominal in the alignment phase and start with two seconds worth of rev up'.  I would love to be proved wrong but I expect the official documentation if it exists, will be quite circular i.e. PHASE1_DURATION is used to set the duration of phase 1.

I find that everything has to be done by experimentation.  I have never had the motor pilot working on Windows, you can easily spend a week working through its errors to get nowhere, as indeed, I have.