In my mind the main difference is steppers always taking full current, that's why we tend to switch to traditional servos past a certain size or use hybrid steppers like the MDrive
If you're micro-stepping a stepper then you're applying different currents to the coils. You can also microstep/openloop a BLDC just like a stepper and you can run a stepper with a closed loop controller just like it's bigger BLDC cousin.
Steppers had a niche in situations where you want to take discrete/accurate steps with very little control circuitry, e.g. printers, disk drivers etc. they're much simpler to work with vs. a closed loop bldc system, require no tuning, less software, etc.
I used to think this but you can actually drive steppers with FOC (if they have appropriate feedback) and modulate the current based on required torque. It’s open-loop steppers that don’t do this.
You can do this but it's very difficult; the high pole count means it requires extremely precise and high-speed feedback to get good torque control on a stepper motor.
In general yes, but there are variable reluctance steppers, which work a little bit different. While a BLDC defines how it is made, a stepper has a couple of different technologies.
In my mind the main difference is steppers always taking full current, that's why we tend to switch to traditional servos past a certain size or use hybrid steppers like the MDrive
If you're micro-stepping a stepper then you're applying different currents to the coils. You can also microstep/openloop a BLDC just like a stepper and you can run a stepper with a closed loop controller just like it's bigger BLDC cousin.
Steppers had a niche in situations where you want to take discrete/accurate steps with very little control circuitry, e.g. printers, disk drivers etc. they're much simpler to work with vs. a closed loop bldc system, require no tuning, less software, etc.
I used to think this but you can actually drive steppers with FOC (if they have appropriate feedback) and modulate the current based on required torque. It’s open-loop steppers that don’t do this.
You can do this but it's very difficult; the high pole count means it requires extremely precise and high-speed feedback to get good torque control on a stepper motor.
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In general yes, but there are variable reluctance steppers, which work a little bit different. While a BLDC defines how it is made, a stepper has a couple of different technologies.