Milling machine stepper motor(Part 2)

In the previous article, we talked about the composition of the milling machine stepper motor and its control ways. Today we look at what features it has.

1. Hold torque

The stepping motor remains energized, but the rotor does not move and has torque output. At this time, the torque is called the holding torque, also known as the maximum static torque. Holding torque is an important measure of the ability of the milling machine stepper motor to withstand external load disturbance.

2. Torque-frequency characteristics and acceleration / deceleration

The output torque of the stepper motor varies with the energization frequency, which is called the torque-frequency characteristic. As the picture shows.

As shown in the figure, f_s is the starting frequency, also known as the sudden jump frequency, the corresponding torque for the starting torque T_s. At the time of starting, the starting torque is greater than the torque T_r at the time of continuous operation due to the presence of the acceleration torque. The starting frequency is much lower than the continuous operating frequency, the starting frequency is generally only a few hertz.

If the starting frequency is too large, the milling machine stepping motor output torque is not enough to overcome the starting torque, it will lead to stepper motor can not start, out of step or stall phenomenon. After the start of the stepping motor, the highest frequency with the continuous rise of the frequency of the energization frequency is called the running frequency f_r, and its value is much larger than the starting frequency. If the stepper motor running frequency is too high, will lead to the output torque is not enough to overcome the load torque, it will be out of step or stall phenomenon, accompanied by howling.

Understand the milling machine stepper motor these characteristics, I hope to help you some.