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FEC (Field Estimated Control)

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offroader
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FEC (Field Estimated Control)

I randomly found this article about a new type of motor control: https://www.crowdsupply.com/iq-motion-control/iq-motor-module/updates/mo...
I was quite interested in it, and I'm constantly wondering if it would be worth the effort to implement it. For many applications, an encoder is necessary and could simplify the controller hardware requirements when many designs suffer from current measurement noise. I would be interested in what more people think about it and whether it is worth developing something like that.

vadicus
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Interesting. Not likely to be worth the trouble though as estimation by definition will be inferior to actual measurements. Of course, there will be some use cases where this would be a good approach but there are a lot of unknowns and tons of testing that needs to be done to get it to work reliably only to get a simulation of FOC. Requiring encoders definitely limits the motor selection. If savings is the goal, there is already a glut of sinewave controllers that can run almost any motor on the cheap requiring only basic DC link current measurement and hall sensors.     

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)

offroader
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I agree with you, and I know that it will definitely not be better than a quality FOC regulator. I also have experience with low-quality FOC regulators that have a big problem running smoothly in sensorless mode. I also have cheap sine wave regulators lying around at home that work well and I like their hardware design, so maybe it would be interesting to improve them in software so that their parameters would be closer to FOC regulators. I am also now trying to study what parameters are necessary for this type of control. In your opinion, what motor parameters are necessary for this type of control?

vadicus
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Sinewave controllers will run almost any sensored motor without issues at low to medium RPMs. They are as quiet as FOC and require minium settings (no FOC detection, etc.). Just current and voltage min/max settings and that's it. Regen works well as well but not all the way to 0 RPMs and it's usually static/non-variable. They are great for simple projects where you just connect phases, battery, throttle and it works. Most have cruise, reverse, power limiting inputs. You don't want more parameters for a basic controller that does the job. Where they lack is the features, obviously, efficiency and torque at high RPMs. If your application requires advanced features like balancing, variable regen all the way to 0 RPM, etc. you chose a more advanced controller.

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)

offroader
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Maybe you convinced me that sine control is sufficient for many applications, but I don't know any open-source and that makes me so sad😀

offroader
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and the sine controller that will work with the motor parameters should work better, right?

vadicus
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There is no shortage of open source controller designs - just a google it. KT controllers, TSDZ2 are just some examples. Some of them even run FOC and the hardware can be had from for as low as $20.

I mean a complete controller for $20. 

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)

offroader
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I really forgot about the OSEC project, it's also a nice project and you're right that it could be easier to port to another hardware and it would be worth continuing with it.