Here is a different way to control a stepper motor. This control method treats the stepper as if it is just a plain old BLDC motor but with 50 poles and 2 phases. Positional accuracy is determined by an encoder, not the number of steps as the controller is not doing "steps" but using the motor as a continuous motion servo. It seems like this could be a retrofit to a machine that uses steppers to give an increased performance while keeping the same motors.
You can read the theory used here: https://en.wikipedia.org/wiki/Vector_control_(motor) What this project offers is not a controller, but Open Source software that runs on any of a shortlist of microcontrollers and uses a long list of sensors and motors. The website was a project design walk-through. This is also, as you can see very low cost, he is using a $5 driver board from eBay. What they are saying is that small steppers have better performance and use less power when driven using their closed-loop algorithm. But it does require that you place a current sensor (Hall effect or in in-line resister) on both phases and drive the stepper with a PWM capable pair of full-H-bridges. What is going on is the control software is measuring current and forcing it to have the desired waveform against the inductance and mechanical loads. https://youtu.be/zcb86TRxTxc Here is the project website https://simplefoc.com/ -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
