Stepper motors are widely used in automation and control systems, and are favored for their precise positioning capabilities and good control characteristics. In many applications, the torque and speed of stepper motors are two key parameters that directly affect the performance and application effects of the motor.
1. Stepper Motor Torque
The stepper motor torque refers to the maximum rotational torque that can be generated by its rotor when the motor is stationary, usually in Newton meters (N·m) or kilogram-force meters (kgf·m). Torque is a key parameter to measure the load driving capacity of a stepper motor. It reflects the ability of the motor to overcome external resistance torque and rotate the load without considering the speed factor.
2. Stepper Motor Speed
The speed of a stepper motor usually refers to the speed of the motor rotor. The operating speed of a stepper motor can usually reach 200 to 500 rpm. Its operating speed is closely related to multiple factors, which allows its speed to be accurately adjusted within a certain range.
3. The Relationship Between Torque and Speed
The output torque of the motor is inversely proportional to the speed. That is, the output torque of the stepper motor is large at low speed, a few hundred revolutions per minute or lower; the torque at high speed rotation state, 1000 rpm-9000 rpm, is very small.
For some working conditions that require high-speed motors, it is necessary to measure the coil resistance, inductance and other indicators of the stepper motor. Selecting a motor with a slightly smaller inductance as a high-speed motor can obtain a larger output torque. Conversely, when low-speed and high-torque are required, it is necessary to select an inductance of more than ten or tens of mH, and a larger resistance.
Stepper Motor Torque and Speed4. Factors Affecting Torque and Speed
4.1 Voltage
Increasing the voltage supplied to the stepper motor helps maintain high torque at high speed. High voltage enables the windings of the stepper motor to charge and discharge faster, allowing the stepper motor to respond quickly.
4.2 Current
The current supplied to the stepper motor winding directly affects the torque. Higher currents result in greater torque, but excessive currents can cause overheating and damage.
4.3 Inductance
Stepper motors have inductive windings that resist changes in current. At high speeds, the inductive winding limits the current flowing into the motor and reduces the torque. Motors with lower inductance generally have better high-speed performance.
4.4 Subdivision
Subdivision is a technique that improves the resolution of stepper motors by dividing each step into small steps. Subdivision not only improves the positioning accuracy and smoothness of stepper motors, but also reduces the torque per step.
4.5 Driver Configuration
The type and configuration of the driver in the stepper motor significantly affects its torque-speed curve. Advanced drivers with higher rated voltage and current regulation can improve the performance of stepper motors by better controlling torque and speed.
Summary
The stepper motor torque and speed are key parameters that affect their performance and application effects. Through reasonable design and control, the advantages of stepper motors can be fully utilized to achieve efficient automation and control.