The current and voltage of the step motor, inductance
These inductance and resistance parameters determine how often the step motor can run. For example, if you're using PWM control, you're going to have a very high frequency and you're going to have a little bit of a step in the motor. Some motors are fine. The motor has a response frequency. This is an essential parameter to control the motor.
The torque size is directly related to the winding number of current and winding; In the case of constant current, the more winding number (and the greater the inductance), the greater the torque. So you understand that the torque = winding number x current understanding can be used to refer to this formula, but it's not, it's a lot more complicated than this formula. High-speed cases, i.e., voltage frequency conversion quickens, winding back emf get bigger, abate forward current, so the speed of the motor torque will be smaller. As for the problem, I can't sure answer, I analysis is that the high frequency, inductance is big, the greater the current weakening, winding circle number is the same, so the inductor motors when high speed low torque.
A small, current high performance will be better.I hope my answer will help you
