Stepper, torque, volts, pps (1 reply)

Hi all

Trying to make some sense of this
Objective : maximize torque and rpm and validate my (mis)conceptions
Application is non reprap

Motor :wantai nema 23, type 57byg621 torque curve attached

[www.wantmotor.com]

Max torque, 12.5 kg cm at 24 V, half step
Halfstep gives 40% more torque than full step, but some say 4988 enegizes both coils at full step too, but can't find it in the spec sheets-confirmation would be great

Typical power supply is 12V so torque=50%?
If a gearbox is used, for torque multplication, this often needs an increase in rps, to keep speed, this increases pps, torque is reduced -high pps drops torque ?-see attached torque curve(also efficiency of gearbox costs up to 50%)

Possible solution:increase volts to max 25 times (according to Gecko) the rated voltage, say max 45/48 volt? (using DRV driver instead of pololu) Driver amps set to motor amps in spec sheet . Motor will run hot. This doubles torque?? (Almost) but assume that BEMF becomes an issue-considering to use L6470 driver for compensation

If microstepping is used, torque as total remains the same, just divided per microstep?
But microstepping increases pps, so lower torque again-as per curve?


Appreciate your help in this

Coolerooney