Field Oriented Control of Permanent Magnet Motors
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange users link it when asked about three-phase motor driving, back EMF and torque versus speed control, as an accessible introduction to FOC.
Recommended by 1 people across 1 different months, 2017 to 2022.
What it is
A Texas Instruments training session on Field Oriented Control (FOC) of permanent magnet motors, using animations and simulations to explain the process. It then introduces observers and shows how they enable sensorless control by removing the shaft sensor. It builds on an earlier session in the same series.
What people said
Recommends user57037 · 2022-12 · Electrical Engineering Stack Exchange · on “Does Back EMF change according to stator current in SM?”
@Zelreedy it is a very big topic. You can search on this term: "Field-oriented control" or "FOC." In the synchronous machine, the current and voltage are both synchronous to the back EMF. Maybe this video will help. [this video]
Cites user109388 · 2017-04 · Electrical Engineering Stack Exchange · on “3 phase motor calculate proper phase voltages”
Yes, driving a 3 phases motor is a non-trivial problem, but there is way to make it simpler. The basics and defining what we want to do First, have a look a this wikipedia article [LINK] and try to get a picture of why you have 3 phases. Your goals is to create a rotating magnetic field, and that will happen if your 3 phases are shifted from 120 degrees. You should see that on your EMF as well. Now I would like to determine the input waveforms to all three phases such that the signal across these same two wires corresponds to the back-emf waveform above. The waveform will be 3 sinusoids shifted from 120 degrees. The real problem is knowing in what direction you want your magnetic field. As f
Cites penguin99 · 2021-02 · Electrical Engineering Stack Exchange · on “Are we controlling the speed or torque when we press the accelerator pedal in an electric car?”
In this video [this video] , at 16:23, the presenter says that when we press the accelerator pedal in an electric car, we are " commanding torque and not speed ". I'm confused here, aren't we making the car go faster (more speed) when we press the pedal? So aren't we in fact commanding speed? Moreover, at 4:27 the animation is depicted in a way showing that higher torque means faster rotation (thus more speed). But, doesn't high torque not always equal high speed for a motor? (Because there exists high torque low speed motors, etc.) Also, in situations where high torque does equal high speeds, then is there no need for speed control at all? Can we go faster or slower by just controlling the torqu