From: Denny Esterline <desterline@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Thu, 16 Sep 2021 09:34:32 -0700
Subject: Re: [EE] Current mode / Torque mode motor driver
Thread-Topic: [EE] Current mode / Torque mode motor driver
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High level, yes. But as they say, the fun is in the details.

No doubt you want to output PWM, then you have to sync the AD to the PWM.
If it's a three-phase motor, then you have to run a commutation algorithm
and then consider how your current sensor(s) are connected to the phases.
(multiple sensors are common for different control algorithms)

Then there's a bunch of corner-cases you need to consider. Reach MIN/MAX
control output without reaching goal current?

Can you be more specific about the motor? There really are a lot of
existing driver options out there that can do this already, depending on
the details of your application.

-Denny


On Thu, Sep 16, 2021 at 8:52 AM Neil <picdude3@narwani.org> wrote:

> I'm having a hard time finding a current-mode / torque-mode motor driver
> and thinking it's time I DIY something.
> High-level thought is to add a small resistor to the ground side, buffer
> and measure that with a microcontroller and dynamically
> increase/decrease the motor output signal from the microcontroller to
> get a specific current.
> Is it as simple as this?
>
> Cheers,
> -Neil.
>
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